Orthopedic Board MCQs: Ankle, Fracture & Scoliosis

About This Board Review Set

This is Part 113 of the comprehensive OITE and AAOS Orthopedic Surgery Board Review series authored by Dr. Mohammed Hutaif, Consultant Orthopedic & Spine Surgeon.

This set has been strictly audited and contains 100 100% verified, high-yield multiple-choice questions (MCQs) modelled on the exact format of the Orthopaedic In-Training Examination (OITE) and the American Academy of Orthopaedic Surgeons (AAOS) board examinations.

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Two distinct learning modes are available:

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Pro Tip: Use keyboard shortcuts A–E to select options, F to flag a question for review, and Enter to jump to the next unanswered question.

Topics Covered in Part 113

This module focuses heavily on: Ankle, Deformity, Fracture, Scoliosis.

Sample Questions from This Set

Sample Question 1: A 6-year-old child sustained a closed nondisplaced proximal tibial metaphyseal fracture 1 year ago. She was treated with a long leg cast with a varus mold, and the fracture healed uneventfully. She now has a 15-degree valgus deformity. What...

Sample Question 2: -The main blood supply to the capital femoral epiphysis in a 10-year-old child is supplied from the...

Sample Question 3: A teenage female is referred to you for evaluation of curvature in her back that was discovered on routine school screening. She is diagnosed with adolescent idiopathic scoliosis. In which of the following scenarios is a bracing program the...

Sample Question 4: The talocrural angle of an ankle mortise x-ray is formed between a line perpendicular to the tibial plafond and a line drawn:...

Sample Question 5: Figure 10 shows the AP radiograph of an ambulatory 76-year-old patient. What is the most appropriate surgical treatment option for this patient?...

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Evidence consistently demonstrates that active recall through spaced MCQ practice yields substantially greater long-term retention than passive reading alone (Roediger & Karpicke, 2006). All questions in this specific module have been algorithmically verified for clinical integrity and complete explanations.

Comprehensive 100-Question Exam

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Question 1

A 6-year-old child sustained a closed nondisplaced proximal tibial metaphyseal fracture 1 year ago. She was treated with a long leg cast with a varus mold, and the fracture healed uneventfully. She now has a 15-degree valgus deformity. What is the next step in management?

Explanation

DISCUSSION: The tibia has grown into valgus secondary to the proximal fracture. This occurs in about one half of these injuries, and maximal deformity occurs at 18 months postinjury. The deformity gradually improves over several years, with minimal residual deformity. Therefore, treatment at this age is unnecessary as there is a high rate of recurrence and complications regardless of technique. The valgus deformity is not a result of physeal injury or growth arrest. Medial proximal tibial hemiepiphysiodesis is an excellent method of correcting the residual deformity but is best reserved until close to the end of growth.
REFERENCES: Brougham DI, Nicol RO: Valgus deformity after proximal tibial fractures in children. J Bone Joint Surg Br 1987;69:482.
McCarthy JJ, Kim DH, Eilert RE: Posttraumatic genu valgum: Operative versus nonoperative treatment. J Pediatr Orthop 1998;18:518-521.
Robert M, Khouri N, Carlioz H, et al: Fractures of the proximal tibial metaphysis in children: Review of a series of 25 cases. J Pediatr Orthop 1987;7:444-449.

Question 2

-The main blood supply to the capital femoral epiphysis in a 10-year-old child is supplied from the

Explanation

Question 3

A teenage female is referred to you for evaluation of curvature in her back that was discovered on routine school screening. She is diagnosed with adolescent idiopathic scoliosis. In which of the following scenarios is a bracing program the most appropriate treatment? Review Topic

Explanation

Bracing is most appropriate for skeletally immature patients with a curve > 20/25 degrees. Thus the patient with a left upper thoracic curve of 15 degrees and right main thoracic curve of 30 degrees in Risser stage 1 of growth meets criteria.
The treatment of adolescent idiopathic scoliosis (AIS) depends on the magnitude and location of curve as well skeletal maturity of the patient. For curves less than 20 degrees, observation is appropriate until skeletal maturity, with closer intervals during
times of peak growth. Curves between 20-25 and 45 degrees in patients who are Risser stage 0,1 or 2 are best treated with bracing to stop progression. Curves with an apex at T7 or below are typically treated with a Boston brace. Curves over 50 degrees generally warrant a discussion about surgery to prevent progression past maturity.
In a landmark study, Weinstein et al. evaluated both a randomized and preference based cohort of bracing versus observation. The trial was stopped early due to efficacy of bracing. The rate of treatment success was 72% after bracing and 48% after observation. Treatment success was strongly correlated to time of brace wear.
Schlenzka et al. reviewed indications, treatment, and complications associated with brace treatment of AIS. They state that further evidence is necessary to evaluate the efficacy of bracing in AIS.
Figure 1, 2, and 3 are radiographs depicting Risser stage 0, 1, and 4 respectively. Illustration B shows radiographs of all Risser stages. Illustration C is the Lenke classification system for idiopathic scoliosis.
Incorrect Answers:

Question 4

The talocrural angle of an ankle mortise x-ray is formed between a line perpendicular to the tibial plafond and a line drawn:

Explanation

DISCUSSION: The talocrural angle is formed by the intersection of a line perpendicular to the plafond with a line drawn between the malleoli (average = 83+/-4deg). When the lateral malleolus is shortened secondary to fracture, this can lead to increased talocrural angle. This malunion leads to lateral tilt of the talus.
Phillips et al looked at 138 patients with a closed grade-4 supination-external rotation or pronation-external rotation ankle fracture. Although the conclusions were limited due to poor follow up, they found the difference in the talocrural angle between the injured and normal sides was a statistically significant radiographic indicator of a good prognosis.
Pettrone et al looked at a series of 146 displaced ankle fractures, and the effect of open or closed treatment, and internal fixation of one or both malleoli. They found open reduction proved superior to closed reduction, and in bimalleolar fractures open reduction of both malleoli was better than fixing only the medial side.

Question 5

Figure 10 shows the AP radiograph of an ambulatory 76-year-old patient. What is the most appropriate surgical treatment option for this patient?

Explanation

DISCUSSION: The patient has a periprosthetic fracture around a loose cemented femoral component. The proximal bone stock is poor; therefore, this fracture may be categorized as Vancouver 3-B. Hip arthrodesis and resection arthroplasty provide suboptimal results, particularly for ambulatory patients. Although impaction allografting may be an option to restore the bone stock in a younger patient, the latter procedure will be very difficult to perform when the proximal bone is poor in quality and fractured. Cementing another component into this wide femur is not an option. The best option for revision of the femoral component in this elderly patient is proximal femoral replacement arthroplasty.
REFERENCES: Malkani AL, Settecerri JJ, Sim FH, et al: Long-term results of proximal femoral replacement for non-neoplastic disorders. J Bone Joint Surg Br 1995;77:351-356.
Parvizi J, Sim FH: Proximal femoral replacements with megaprostheses. Clin Orthop 2004;420:169-175.

Question 6

A diskectomy is performed in which the disk space is not aggressively debrided. When compared to techniques that involve aggressive debridement of the disk space, this results in

Explanation

DISCUSSION
This patient has disk herniation at the left L5-S1 level. This will generally affect the traversing S1 nerve. The S1 dermatome is on the lateral aspect and sole of the foot.
Surgical treatment generally involves a diskectomy with removal of the herniated fragment. This can be performed via a conventional open approach or minimally invasive endoscopic technique. Several recent meta-analyses have demonstrated equivalent outcomes with regard to leg pain and clinical outcomes. Although minimally invasive techniques have been associated with an increased rate of dural tear, the overall complication rate between the 2 techniques is not significantly different. Several studies have demonstrated a substantial learning curve associated with minimally invasive techniques, and the rate of complications decreases significantly with surgeon experience.
When performing a diskectomy, the herniated fragment alone can be removed (sequestrectomy) or some of the disk that remains in the disk space can be removed (complete diskectomy). Studies have shown no change in surgical time, blood loss, length of stay, or surgical complications when performing a sequestrectomy (compared to a more complete diskectomy). A sequestrectomy is associated with a higher rate of recurrent disk herniation at the surgical level.
RECOMMENDED READINGS
Kamper SJ, Ostelo RW, Rubinstein SM, Nellensteijn JM, Peul WC, Arts MP, van Tulder MW. Minimally invasive surgery for lumbar disc herniation: a systematic review and meta-analysis.
Eur Spine J. 2014 May;23(5):1021-43. doi: 10.1007/s00586-013-3161-2. Epub 2014 Jan 18.
PubMed PMID: 24442183. View Abstract at PubMed
Dasenbrock HH, Juraschek SP, Schultz LR, Witham TF, Sciubba DM, Wolinsky JP, Gokaslan ZL, Bydon A. The efficacy of minimally invasive discectomy compared with open discectomy: a meta-analysis of prospective randomized controlled trials. J Neurosurg Spine. 2012 May;16(5):452-62. doi: 10.3171/2012.1.SPINE11404. Epub 2012 Mar 9. PubMed PMID:

Question 7

Which of the following would be associated with the spinal deformity shown in Figures 79a and 79b? Review Topic

Explanation

The images delineate progressive osteoporotic collapse. As outlined by Kado and associates, Schlaich and associates, and Gold and associates, the progression of spinal deformity and the functional consequences of vertebral compression fractures are persistent even in those patients who are pain free. Vertebral compression fractures are associated with deteriorating gait, early satiety, further future fracture risk, and deteriorating lung function.

Question 8

A 25-year old right-hand dominant professional baseball pitcher complains of posteromedial right elbow pain that is worsened by throwing. He also reports occasional paresthesias in his small and ring finger after lengthy bullpen sessions. On examination, he is tender along the medial olecranon and complains of pain when extending the elbow >- 20° of extension. He has negative valgus stress, moving valgus stress, and milking maneuver tests. He is stable to varus stress, chair rise, and lateral pivot shift tests. Radiographs reveal a small osteophyte along the posteromedial border of the olecranon. What is the most likely diagnosis?

Explanation

A patient sustains a displaced diaphyseal humerus fracture following a motor vehicle accident. Open reduction internal fixation is indicated due to concomitant lower extremity trauma and is planned through an anterior approach. Which intramuscular interval is exploited during the deep dissection of the mid-humerus in this approach?

A. Lateral head of triceps (radial nerve) and brachialis

(musculocutaneous nerve)

B. Lateral head of the triceps (radial nerve) and biceps brachii

(musculocutaneous nerve)

C. Lateral brachialis (radial nerve) and medial brachialis

(musculocutaneous nerve)

D. Brachialis (musculocutaneous nerve) and coracobrachialis

(musculocutaneous nerve)

Question 9

A 60-year-old woman with a history of breast cancer has progressive paraparesis. The MRI scan is shown in Figure 28. What form of management is most likely to restore or maintain ambulation?

Explanation

DISCUSSION: Surgical decompression and stabilization have been shown to be the most effective means of improving neurologic function. Decompression is most reliably done from the side of the compression, which is anterior in this patient.
REFERENCES: Harrington KD: Metastatic tumors of the spine: Diagnosis and treatment. J Am Acad Orthop Surg 1993;1:76-86.
Siegal T, Siegal T: Current considerations in the management of neoplastic spinal cord compression. Spine 1989;14:223-228.

Question 10

What is the most common cause of errors that harm patients? Review Topic

Explanation

The AMA report identified communication breakdown as the most common cause of errors that harm patients. It is extremely important to learn to communicate effectively with your patients. Understanding cultural and language differences helps avoid communication errors.

Question 11

Halo treatment for preadolescent children typically requires the use of which of the following? Review Topic

Explanation

The complication rate with halo vest treatment in children is reported to be as high as 68% in contrast to a 36% complication rate in adults. These complications include not only pin tract infections, but also skull penetration. Multiple pins allow for the early removal of pins without fixation consequences should pin site infections begin to develop. Moreover, there is significant variability in the insertional torque applied by a variety halo pin torque wrenches, including those from the same manufacturer. Consequently, the use of a large number of pins (8 to 12) placed a very low insertional torque (1 to 5 in-lb) in children is recommended. A CT scan of the head should also be considered to assess for the thickest areas of the skull suitable for pin application.

Question 12

What is the most appropriate treatment for a chordoma involving the sacrum?

Explanation

DISCUSSION: Chordomas are very radio- and chemotherapy resistant; therefore, en bloc resection with a negative margin is the preferred treatment. Lesions at or below S3 can be resected without compromising pelvis stability, and continence usually is maintained. The mean survival rate for patients with sacral chordomas is approximately 7 years. Patients with chordoma of the mobile (cervical, thoracic, or lumbar) spine have a mean survival rate of approximately 5 years. This difference is most likely the result of an earlier diagnosis.
REFERENCES: Fardin DF, Garfin SR, Abitbol J, et al (eds): Orthopaedic Knowledge Update: Spine 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 123-133.
Stener B, Gunterberg B: High amputation of the sacrum for extirpation of tumors: Principles and technique. Spine 1978;3:351-366.
Stener B: Resection of the sacrum for tumors. Chir Organi Mov 1990;75:S108-S110.

Question 13

Figure below depicts the radiograph obtained from a 52-year-old woman who has leg-length inequality and chronic, activity-related buttock discomfort. This problem has been lifelong, but it is getting worse and increasingly causing back pain. What is the best current technique for total hip arthroplasty?

Explanation

DISCUSSION:
A high hip center is not recommended for Crowe type IV hips because of the lack of acetabular bone and altered hip biomechanics. An anatomic center is a better option but necessitates a technique to address the tight soft-tissue envelope. A trochanteric osteotomy with progressive femoral shortening has been described but can be prone to trochanter nonunion. Iliofemoral lengthening prior to surgery has been described but may not be tolerated by all patients. A shortening subtrochanteric osteotomy avoids trochanter nonunion and allows adjustment of femoral anteversion. Fixation of the osteotomy can include a stem with distal rotational control, plate fixation, a step versus oblique cut, or strut grafts.

Question 14

A 23-year-old woman falls from a bicycle and sustains a right knee injury. Figures 12a through 12d show radiographs and MRI scans of the knee. What is the most likely diagnosis?

Explanation

DISCUSSION: The radiographs and MRI scans both show an avulsion of the anterior cruciate ligament, which has been described by Meyers and McKeever in three different fracture patterns. Type I fractures are nondisplaced or have minimal displacement of the anterior margin. Type II fractures have superior displacement of their anterior aspect with an intact posterior hinge. Type III fractures are completely displaced. Although the injury is visible on the radiographs, it is more subtle in adults than children. Thus, MRI is helpful in clarifying this injury in adults. Open or arthroscopic reduction and internal fixation is recommended for type II and type III fractures that do not respond to closed reduction.
REFERENCES: Meyers MH, McKeever FM: Fracture of the intercondylar eminence of the tibia. J Bone Joint Surg Am 1970;52:1677-1684.
Wiss DA, Watson JT: Fractures of the tibial plateau, in Rockwood CA, Green DP, Bucholz RW, et al (eds): Rockwood and Green’s Fractures in Adults. Philadelphia, PA, Lippincott-Raven, 1996, pp 1920-1953.
Lubowitz JH, Elson WS, Guttmann D: Arthroscopic treatment of tibial plateau fractures: Intercondylar eminence avulsion fractures. Arthroscopy 2005;21:86-92.

Question 15

A 23-year-old soccer player sustains a grade III complete posterior cruciate ligament (PCL) tear after colliding with another player. In reconstructing the PCL, it is optimal to reconstruct the

Explanation

DISCUSSION: The PCL is a nonisometric structure with nonuniform tension during knee motion, with maximum tension at 90° of flexion. While the posteromedial PCL fibers have been found to be the most isometric, the anterolateral fibers represent the bulk of the ligament. Studies have suggested that anterior placement of the femoral tunnel is superior to placement in an isometric position. The anterolateral bundle tightens as the knee flexes; therefore, it is optimal to tension the graft at 90° of flexion.
REFERENCES: Harner CD, Xerogeanes JW, Livesay GA, et al: The human posterior cruciate ligament complex: An interdisciplinary study. Ligament morphology and biomechanical evaluation. Am J Sports Med 1995;23:736-745.
Burns WC II, Draganich LF, Pyevich M, Reider B: The effect of femoral tunnel position and graft tensioning technique on posterior laxity of the posterior cruciate ligament-reconstructed knee. Am J Sports Med 1995;23:424-430.

Question 16

Botulinum toxin is used to treat vasospastic disorders of the hand such as the Raynaud phenomenon to improve digital perfusion and reduce pain. Botulinum toxin enables which transmitter to be unopposed, resulting in vasodilation?

Explanation

EXPLANATION:
Nitric oxide is the only transmitter listed that is not inhibited by botulinum toxin. Substance P and glutamate are inhibited by botulinum toxin from release by pain nociceptors, thus reducing pain. Fonseca and associates have postulated that botulinum toxin inhibits the RhoA kinase pathway by blocking reactive oxygen species, which in turn does not allow actin/myosin to activate, thus preventing vasoconstriction of smooth muscle. Blocking the RhoA kinase pathway allows the action of nitric oxide to be unopposed, causing vasodilation. Nitric oxide is a potent vasodilator. Thus, botulinum toxin promotes nitric oxide activity to increase vasodilation.

Question 17

The nucleus pulposus of the intervertebral disk consists of chondrocyte-like cells that have a limited vascular supply and generate energy through which of the following?

Explanation

The intervertebral disk is an avascular structure in the adult. Nucleus pulposus cells have a critical need for glucose because they obtain their energy primarily by glycolysis, even in the absence of oxygen. Disk cells do not require oxygen to remain alive but they die at low glucose levels or acidic pH. Nutrients are supplied from the blood vessels at the margins of the disk and have to traverse the cartilaginous end plate to reach the disk cells. The loss of the nutrient supply through the vertebral body will starve the cells in the disk center and may be a major factor in disk degeneration.

Question 18

A 75-year-old woman is undergoing a T10-S1 lumbar decompression and fusion for severe degenerative scoliosis. During the deformity corrective maneuver, intraoperative neuromonitoring revealed a sustained 80% decrease in somatosensory-evoked potential (SSEP) amplitudes. Appropriate lead placement and

Explanation

The most appropriate management is discontinuation of the spinal instrumentation procedure, including releasing any distractive forces. Given the ongoing changes, proceeding with the procedure and/or resetting the baseline amplitudes is inadvisable. If the SSEPS amplitudes fail to return in a timely fashion, it is strongly recommended to consider a wake-up test. The purpose of intraoperative neuromonitoring is to provide a real-time assessment of the functional integrity of the central and peripheral nervous systems during surgery to prevent iatrogenic injury. Sustained decreased SSEP amplitudes of greater than 50% and transcranial electric Motor-Evoked Potentials (tceMEP) amplitudes of greater than 75% are indicative of a possible significant intraoperative neurologic complication. Although intraoperative corticosteroids might be helpful, especially in the event of a continued SSEP change, the most important next step would be to release the distractive forces and reevaluate the patient's neurologic status.

Question 19

What strategy has proven most effective in preventing transmission of methicillin-resistant Staphylococcus aureus among teammates? Review Topic

Explanation

Prevention is the key to controlling infections among athletes. Proper hygiene is critical and should mandate showering, hand washing, wearing breathable clothing, and shower sandals. The sharing of towels or athletic equipment should be forbidden. Daily skin surveillance by athletes, trainers, and physicians can allow early recognition and treatment initiation during the early stages of infection, limiting risk for further transmission. Additionally, disinfecting shared equipment, covering lesions with occlusive dressing during sporting activity, and restricting the contact activities of infected athletes can limit risk for an infectious outbreak among teammates.

Question 20

During fracture healing, granulation tissue tolerates the greatest strain before failure so that mature bone can eventually bridge the fracture gap during healing. What is the definition of strain?

Explanation

Strain is defined as the change in length/original length (L) and is created by a deformation of a material from an applied force.
The mechanical environment at the fracture site has a major influence on fracture healing. Granulation tissue can withstand higher strain, which stabilizes the mechanical environment and forms a scaffold on which cartilage and bone eventually form; this occurs after strain decreases incrementally. Optimal healing, however, depends on duration, rate, timing and type of mechanical influence. Bone is formed by osteoblasts that are adapted to the very low strains of over 1% change in length. Osteoblast synthesis and proliferation is stimulated at uniaxial strain of between 0.3% and 2.8%. It is known that limited inter-fragmentary movement of 0.2 mm to 1 mm is optimal for fracture healing, resulting in promotion of callus and increase in rigidity. Excessive movement, on the other hand, prolongs fracture healing. Researchers have identified that tissue strain of 2% is suitable for primary bone healing and secondary bone healing takes place at tissue strain of 2-10%. Strain of 10-100% results in fibrous tissue formation and 100% strain to non-union. This is known as Perren's theory.
Stokes published a review article on the effects of stress on bone healing and growth, and notes the importance of the 'Hueter-Volkmann Law' (growth is retarded by increased mechanical compression, and accelerated by reduced loading in comparison with normal values) in bone growth. Stokes also notes that sustained compression of physiological magnitude inhibits growth by 40% or more, while distraction increases growth rate by a much smaller amount.
Illustration A shows an example of a stress-strain curve, with several key definitions labeled on the diagram.
Incorrect Answers:

Question 21

The sublime tubercle of the elbow serves as the insertion site of the Review Topic

Explanation

The anterior bundle originates on the anteroinferior medial humeral epicondyle and inserts on the medial portion of the coronoid, known as the sublime tubercle.

Question 22

.What is the most appropriate treatment if instability is present at the time of evaluation?

Explanation

Question 23

The vascularity of the digital flexor tendons is significantly richer in what cross-sectional region?

Explanation

DISCUSSION: The vascularity of the dorsal portion of the digital flexor tendons is considerably richer than the volar portion. The other regions are not preferentially more vascular.
REFERENCES: Hunter JM, Scheider LH, Makin EJ (eds): Tendon Surgery in the Hand. St Louis, MO, Mosby, 1987, pp 91-99.
Gelberman RH, Khabie V, Cahill CJ: The revascularization on healing flexor tendons in the digital sheath: A vascular injection study in dogs. J Bone Joint Surg Am 1991;73:868-881.

Question 24

During cemented total hip arthroplasty, peak pulmonary embolization of marrow contents occurs when the

Explanation

DISCUSSION: Peak embolization is observed during femoral stem insertion. Embolization is also observed during acetabular preparation and hip reduction.
REFERENCES: Lewallen DG, Parvizi J, Ereth MH: Perioperative mortality associated with hip and knee arthroplasty, in Morrey BF (ed): Joint Replacement Arthroplasty, ed 3. Philadelphia, PA, Churchill-Livingstone, 2003, pp 119-127.
Ereth MH, Weber JG, Abel MD, et al: Cemented versus noncemented total hip arthroplasty: Embolism, hemodynamics, and intrapulmonary shunting. Mayo Clin Proc 1992;67:1066-1074.

Question 25

A 20-year-old male military recruit reports a 5-day history of progressive deep groin pain that is made worse with weight-bearing activities and running. His initial coronal T2-weighted MRI scan is shown in Figure 75. His initial treatment should consist of which of the following? Review Topic

Explanation

The MRI scan findings and patient history demonstrate a compression-sided femoral neck stress fracture. The stress fracture on the coronal MRI scan involves about one third of the width of the femoral neck. Surgical treatment would be recommended for tension-sided fractures of the femoral neck. The most appropriate initial treatment is protected weight bearing, with close examination and imaging follow-up. Skeletal traction is not currently used for nondisplaced femoral neck stress fractures, and there is no indication for open reduction and internal fixation. There is no documented role for pulsed ultrasound or calcium supplements in the acute treatment of stress fractures.

Question 26

What is the primary indication for performing an arthroscopic synovectomy on a patient with hemophilia that is the result of factor VIII deficiency?

Explanation

DISCUSSION: Improved medical management has changed musculoskeletal outcomes for individuals with hemophilia. Patients with severe hemophilia receiving prophylactic administration of factor VIII may never develop a target joint that requires further orthopaedic intervention. Patients with moderate hemophilia and those patients with severe hemophilia not receiving prophylactic treatment will still develop joints that have recurrent hemarthroses. When recurrent hemarthrosis continues despite optimal medical management, synovectomy is indicated. While synovectomy is predictable in its ability to decrease joint bleeding, it does not necessarily improve joint range of motion or prevent the development of hemophilic arthropathy over time. It will not reverse articular damage to the joint once it has developed.
REFERENCES: Dunn AL, Busch MT, Wyly JB; et al: Arthroscopic synovectomy for hemophilic joint disease in a pediatric population. J Pediatr Orthop 2004;24:414-426.
Journeycake JM, Miller KL, Anderson AM, et al: Arthroscopic synovectomy in children and adolescents with hemophilia. J Pediatr Hematol Oncol 2003;25:726-731.

Question 27

A 50-year-old man reports left shoulder pain and weakness after undergoing a lymph node biopsy in his neck 2 years ago. Examination reveals winging of the left scapula. Electromyography shows denervation of the trapezius. Surgical treatment for this condition involves

Explanation

DISCUSSION: The muscle transfer procedure most commonly performed for trapezius paralysis is the Eden-Lange procedure. Trapezius paralysis in this patient is secondary to iatrogenic injury to the spinal accessory nerve during lymph node biopsy. In this procedure, the levator scapulae and rhomboid minor and major muscles are transferred laterally. Pectoralis transfer to the inferior border of the scapula is used as a dynamic transfer for serratus anterior winging.
REFERENCES: Kuhn JE, Plancher KD, Hawkins RJ: Scapular winging. J Am Acad Orthop Surg 1995;3:319-325.
Langenskiold A, Ryoppy S: Treatment of paralysis of the trapezius muscle by Eden-Lange operation. Acta Orthop Scand 1973;44:383-388.
Romero J, Gerber C: Levator scapulae and rhomboid transfer for paralysis of trapezius: The Eden-Lange procedure. J Bone Joint Surg Br 2003;85:1141-1145.

Question 28

A pediatric orthopaedic surgeon refers a child to a neurologist. The neurologist’s office requests the office records of the pediatric orthopaedic surgeon. To maintain Health Insurance Portability and Accountability Act (HIPAA) compliance, what must the surgeon obtain from the parent(s) prior to sending records?

Explanation

The privacy rules do not require an individual’s written authorization for certain permitted or required uses and disclosures of the medical records. Patient or parental authorization is not required for disclosures for certain purposes related to treatment, payment, or health care operations. Specifically, HIPAA does not require a covered entity to obtain patient authorization for many of the health care industry’s most fundamental activities such as providing care.

Question 29

An 8-month-old infant has an infection of the fingertip as shown in Figure 22. If neglected, the anticipated path of ascending infection is the fingertip, the flexor sheath, and the

Explanation

DISCUSSION: The flexor sheaths are in continuity with the deep spaces of the hand. The flexor sheaths of the thumb and little finger communicate with the radial and ulnar bursae, respectively, and these two bursae commonly communicate. The central digits do not communicate as readily with deep spaces of the hand but if flexor tendon sheath infection of the index, long, and right fingers is neglected, the potential exists for rupture into the deep midpalmar spaces.
REFERENCES: Peimer CA (ed): Surgery of the Hand and Upper Extremity: Acute and Chronic Sepsis. New York, NY, Mcgraw Hill, 1996, pp 1735-1741.
Trumble TE (ed): Hand Surgery Update 3: Hand, Elbow and Shoulder. Rosemont, IL, American Society for Surgery of the Hand, 2003, pp 445-446.

Question 30

Figure 10 is an anteroposterior pelvis radiograph of an 82-year-old man who had right hip pain that began 2 weeks ago but has since resolved with use of over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs). Currently he has no pain. Examination of his hip shows decreased internal rotation and minimal pain at the extremes of motion. What is the most appropriate treatment at this point?

Explanation

DISCUSSION
The radiograph shown is consistent with Paget disease of the bone. It demonstrates classic findings of widened lamellae and disorganized sclerotic and lytic areas. The cause is not clearly defined, but may be linked to a viral infection and subsequent alterations of osteoblastic and osteoclastic activity. Most patients are asymptomatic, and Paget disease is often found incidentally on radiographs. In this case, the patient’s symptoms likely were caused by hip arthritis, but Paget disease can cause diffuse bone pain in some cases. Considering the patient’s mild and short-term symptoms, observation and NSAID use is most appropriate. An MRI scan or biopsy is indicated if sarcomatous transformation is suspected, but this condition is rare and is associated with a substantial, unrelenting increase in pain. SPEP and UPEP are tests for multiple myeloma, of which the radiographs show no signs.
RECOMMENDED READINGS
Ralston SH. Pathogenesis of Paget's disease of bone. Bone. 2008 Nov;43(5):819-25. doi: 10.1016/j.bone.2008.06.015. Epub 2008 Jul 11. Review. PubMed PMID: 18672105.View Abstract at PubMed
Bonenberger E, Einhorn T. Metabolic bone diseases. In: Callaghan JJ, Rosenberg
AG, Rubash HE, eds. The Adult Hip. 2nd ed. Philadelphia, PA: Lippincott Williams 14
& Wilkins; 2007:514-533.

Question 31

A 30-year-old farmer undergoes replantation of an above-the-elbow amputation. What form of management is most important following this surgery?

Explanation

DISCUSSION: After major limb replantation, the occurrence of ischemic rhabdomyonecrosis can result in lactic acidosis and myoglobulinemia. These complications can be limited by rapid repair of the arterial supply, potentially using a shunt before skeletal stability. Repair of the venous system should be performed after repair of the artery. High volume fluid replacement will maintain a diuresis, thus limiting the complications from myoglobulinemia.
REFERENCES: Wood MB: Replantations about the elbow, in Morrey BF (ed): The Elbow and Its Disorders. Philadelphia, PA, WB Saunders, 1985, pp 472-480.
Goldner RD, Nunley JA: Replantation proximal to the wrist, in Wood MD (ed) Hand Clinics: Microsurgery. Philadelphia, PA, WB Saunders, 1992, pp 413-425.

Question 32

After making a tackle, a football player is found prone and unconscious without spontaneous respirations. Initial management should consist of

Explanation

DISCUSSION: The on-field evaluation and management of a seriously injured athlete requires that health care teams have a game plan in place and proper equipment that is readily available. The initial step, which consists of stabilizing the head and neck by manually holding them in a neutral position, is then followed by assessment of breathing, pulses, and level of consciousness. If the athlete is breathing, management should consist of mouth guard removal and airway maintenance. If the athlete is not breathing, the face mask should be removed, with the chin strap left in place. The airway must be established, followed by initiation of assisted breathing. CPR is instituted only when breathing and circulation are compromised. In the unconscious athlete or if a cervical spine injury is suspected, the helmet must not be removed until the athlete has been transported to an appropriate facility and the cervical spine has been completely evaluated.
REFERENCES: McSwain NE, Garnelli, RL: Helmet removal from injured patients. Bull of Am Coll Surg 1997;82:42-44.
Vegso JJ: Field evaluation and management of head and neck injuries. Post Grad Adv Sport Med 1987;10:2-10.

Question 33

A 29-year-old woman was injured in a high-speed motor vehicle accident 3 hours ago. Radiographs are shown in Figures 7a through 7e. Her right foot injury is open and contaminated. Her associated injuries include a closed head injury and a ruptured spleen requiring resection. She has had 6 units of packed red blood cells and the trauma surgeon has turned her care over to you. Her current base deficit is 10 and her urinary output has averaged 0.4 mL/kg for the last 2 hours. What is the best treatment at this time?

Explanation

DISCUSSION: The patient appears to be a borderline or unstable surgical patient following her initial trauma and spleenectomy (high base excess and low urine output). She needs continued resuscitation and minimal additional blood loss. This is best accomplished with irrigation and debridement of the ankle, external fixation of the ankle, foot, and femur, and splinting of the forearm. A traction pin for the femoral fracture will not control bleeding as well as an external fixator. Intramedullary nailing of the femur and open reduction and internal fixation of the forearm would be appropriate in patients that are euvolemic and stable.
REFERENCES: Pape HC, Hildebrand F, Pertschy S, et al: Changes in the management of femoral shaft fractures in polytrauma patients: From early total care to damage control orthopedic surgery. J Trauma 2002;53:452-461.
Taeger G, Ruchholtz S, Waydhas C, et al: Damage control orthopedics in patients with multiple injuries is effective, time saving, and safe. J Trauma 2005;59:409-416.
Harwood PJ, Giannoudis PV, van Griensven M, et al: Alterations in the systemic inflammatory response after early total care and damage control procedures for femoral shaft fracture in severely injured patients. J Trauma 2005;58:446-452.
Renaldo N, Egol K: Damage-control orthopaedics: Evolution and practical applications.

Am J Orthop 2006;35:285-291.

Question 34

Figures 1 and 2 are the radiographs of a 40-year-old woman who sustained a twisting injury to her lower extremity. What additional information or studies are important in determining treatment options?

Explanation

Age greater than 70 years.
Fracture pattern in Figure A
Significant medical comorbidities.
Fracture pattern in Figure B
Fracture pattern in Figure C
The patient has been treated with non-operative management for her proximal humerus fracture. Operative management should be considered in patients with head splitting proximal humerus fractures and in those with dislocations that cannot be reduced.
Head splitting proximal humerus fractures should be treated with operative management. Open reduction internal fixation versus hemiarthroplasty are used to treat this type of fracture. Surgical management is also considered in proximal humerus fractures in young patients, in fractures where the greater tuberosity is
displaced >5 mm, and in proximal humerus fractures associated with humeral shaft fractures.
Koval et al. studied 104 patients with one-part proximal humerus fractures treated non-operatively, and found 80% with good or excellent results. They also found that 90% of patients treated non-operatively had either no or mild pain about the shoulder at follow-up.
Lefevre-Colau et al. performed a randomized prospective study on 74 patients with an impacted proximal humerus fracture. One group was treated with early mobilization of the shoulder (within 3 days after the fracture) while the other group was immobilized for 3 weeks followed by physiotherapy. They concluded that early mobilization was safe and allowed for quicker return to functional use of the affected limb.
Figure A shows an AP radiograph of a right minimally displaced greater tuberosity proximal humerus fracture. Figure B shows AP and axillary radiographs of a right head split proximal humerus fracture that is posteriorly dislocated. Figure C shows an AP radiograph of a right minimally displaced Salter Harris II proximal humerus fracture. Illustration A shows an AP radiograph of a left valgus impacted proximal humerus fracture with a greater tuberosity fragment displaced >5mm treated with ORIF.
Incorrect Answers:

Question 35

Which of the following types of displaced posterior pelvic disruptions must undergo anatomic reduction and internal fixation to ensure the best clinical outcome?

Explanation

DISCUSSION: Although all of the above displaced injuries require reduction, the sacroiliac joint dislocation is a ligamentous injury. Without fixation, healing is unlikely and the result will be a painful dislocation. Both Holdsworth and Tile showed that the sacroiliac joint must be reduced anatomically and stabilized. The injuries through bone will unite fairly rapidly and, if reduced and stabilized with traction or external fixation, will generally result in an acceptable outcome unless modified by other associated problems such as neurologic injury.
REFERENCES: Tile M: Fractures of the Pelvis and the Acetabulum. Baltimore, MD, Williams and Wilkins, 1995.
Holdsworth F W: Dislocation and fracture dislocation of the pelvis. J Bone Joint Surg Br 1948;30:461-465.
Henderson RC: The long-term results of nonoperatively treated major pelvic disruptions. J Orthop Trauma 1989;3:41-47.

Question 36

03 A 35 year old man sustains a dislocation of his dominant shoulder in a fall. The shoulder is reduced and placed in a sling, but returns 6 hours later with shoulder dislocated again, despite use of a sling. A CT scan is shown in figure 36. Management should now consist of

Explanation

AM J Sports Med 1998;26:41-45 JBJS Am 1993;75:479-484
back to this question go to explanation

Question 37

A 25-year-old man has a mass on the medial aspect of the left knee. He reports that the mass has been present for several years, but a recent increase in physical activity has resulted in periodic tenderness. Radiographs are shown in Figures 13a and 13b. What is the most likely diagnosis?

Explanation

DISCUSSION: The radiographs reveal a sessile lesion projecting from the medial aspect of the distal femur. The lesion shares the cortex with the bone and the base communicates with the medullary space of the femur. This is the classic appearance of an osteochondroma, the most common benign tumor of bone.
REFERENCES: Menendez LR (ed): Orthopaedic Knowledge Update: Musculoskeletal Tumors. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 103-111.
Parsons TW: Benign bone tumors, in Fitzgerald R Jr, Kaufer H, Malkani A (eds): Orthopaedics. Philadelphia, PA, Mosby International, 2002, pp 1027-1035.

Question 38

What is the most common maxillofacial/dental injury in ice hockey?

Explanation

DISCUSSION: Lahti and associates reported that the most common dental injury in a study of 479 injured ice hockey players was a noncomplicated crown fracture, which accounted for 43.5% of all maxillofacial/ dental injuries. The most common cause of injury was a blow from an ice hockey stick. As a cause of injury, the stick was approximately three times as common in games as in training, and only 10% of injured players wore some sort of protective guard. A tooth avulsion is a partial or complete
displacement of the tooth from aleveolar support. A crown fracture is an incomplete loss or fracture of the tooth enamel without loss of the tooth. The other injuries (mandible fracture, lip laceration, tooth
avulsion, and temporomandibular contusion) occur but are not nearly as common.
REFERENCES: Lahti H, Sane J, Ylipaavalniemi P: Dental injuries in ice hockey games and training. Med Sci Sports Exerc 2002;34:400-402.
Minkoff J, Stecker S, Varlotta GP, et al: Ice hockey, in Fu FH, Stone DA (eds): Sports Injuries, ed 2.
Philadelphia, PA, 2001, pp 516-517.

Question 39

When compared to traditional open repair through a posterior incision, percutaneous Achilles tendon repair clearly results in a reduction of what complication?

Explanation

DISCUSSION: Prospective studies, including randomized and randomized multicenter reports, have shown that percutaneous or mini-open acute Achilles tendon repair has comparable functional results when compared to traditional open techniques. Calder and Saxby reported one superficial infection out of 46 patients with a mini-open repair; Assal and associates and Cretnik and associates had no wound complications or infections. The other complications have not proved to be less likely with the mini-open or percutaneous technique.
REFERENCES: Assal M, Jung M, Stern R, et al: Limited open repair of Achilles tendon ruptures:

A technique with a new instrument and findings of a prospective multicenter study. J Bone Joint Surg Am 2002;84:161-170.
Calder JD, Saxby TS: Early, active rehabilitation following mini-open repair of Achilles tendon rupture: A prospective study. Br J Sports Med 2005;39:857-859.
Cretnik A, Kosanovic M, Smrkolj V: Percutaneus versus open repair of the ruptured Achilles tendon: A comparative study. Am J Sports Med 2005;33:1369-1379.

Question 40

A 60-year-old woman with rheumatoid arthritis has atlanto-axial instability and basilar invagination. What MRI findings would suggest the need for cervical fusion?

Explanation

DISCUSSION: The cervical medullary junction should be 135° or greater. An angle of 125° suggests compression of the cervical medullary junction. Other findings supporting surgical intervention include a cord diameter in flexion of less than 6 mm or less than 13 mm of space available for the cord.
REFERENCES: Clark CR (ed): The Cervical Spine, ed 3. Philadelphia, PA, Lippincott Williams & Wilkins, 1998, pp 700-701.
Monsey RB: Rheumatoid arthritis of the cervical spine. J Am Acad Orthop Surg

1997;5:240-248.
Bundschuh C, Modic MT, Kearney F, et al: Rheumatoid arthritis of the cervical spine: Surface-coil MR imaging. Am J Roentgenol 1988;151:181-187.

Question 41

A 30-year-old patient is indicated for distal femoral osteotomy. This procedure results in survivorship with

Explanation

CLINICAL SITUATION FOR QUESTIONS 65 THROUGH 67
Figures 65a and 65b are the radiographs of an 80-year-old woman with long-standing knee pain who has failed nonsurgical treatment that includes a structured physical therapy program, nonsteroidal anti-inflammatory medications, and intra-articular steroid injections. Her radiographs reveal significant degenerative changes. She has experienced some cognitive decline during the last several years and poorly tolerates pain medications, but she remains very active.

Question 42

Figures A and B show the six-month follow-up radiographs of a 62-year-old woman who sustained a hip fracture in a fall. Prior to the fall, the patient was active and had no difficulty with ambulation. The patient underwent open reduction and internal fixation with a sliding hip screw device. She has difficulty with ambulation, continues to walk with a walker, and reports startup pain. What is the most appropriate management at this time? Review Topic

Explanation

The radiographs demonstrate a healed fracture with penetration of the screw through the femoral head into the acetabulum as well as osteonecrosis and collapse of the femoral head (Figure 129b). Conversion to total hip arthroplasty with a long stem is necessary to bypass the femoral cortical defects from the screw holes. A primary tapered stem is not appropriate because of the proximal femoral deformity and the stress risers associated with the screw holes. Removal of hardware, valgus osteotomy, and revision of the internal fixation are not appropriate in the presence of the femoral head collapse and acetabular penetration.

Question 43

Which of the following lesions is best suited for autologous chondrocyte implantation?

Explanation

DISCUSSION: Articular chondrocyte implantation is best performed for focal chondral defects of one area of the joint. It is not indicated for osteoarthritis.
REFERENCES: Mandelbaum BR, Brown JE, Fu F, et al: Articular cartilage lesions of the knee. Am J Sports Med 1998;26:853-861.
Minas T, Nehrer S: Current concepts in the treatment of articular cartilage defects. Orthopedics 1997;20:525-538.
Brittberg M, Lindahl A, Nilsson A, Ohlsson C, Isaksson O, Peterson L: Treatment of deep cartilage defects in the knee with autologous chondrocyte transplantation. N Engl J Med 1994;331:889-895.

Question 44

A 42-year-old man reports the recent onset of right hip pain. A radiograph and MRI scan are shown in Figures 38a and 38b. A WBC count, erythrocyte sedimentation rate, and hip aspiration are within normal limits. Management should now consist of

Explanation

DISCUSSION: Transient osteoporosis of the hip is an uncommon problem, usually affecting women in the last trimester of pregnancy and middle-aged men. Symptoms include pain in the involved hip with temporary osteopenia; however, there is no joint space involvement. In this patient, the imaging findings are consistent with transient osteoporosis. Short TR/TE (repetition time/echo time) images reveal diffusely decreased signal intensity in the femoral head and intracapsular region of the femoral neck. Increased signal intensity is seen with increased T₂-weighting. Within a few months, the pain, as well as the imaging findings, will completely resolve without intervention. Distinguishing the diffuse features of transient osteoporosis of the hip from the segmental findings of osteonecrosis is essential. Unlike transient osteoporosis of the hip, osteonecrosis will have a double-density signal on MRI and may progress radiographically. Surgical intervention and oral corticosteriods are not indicated for treatment. Protected weight bearing until the pain resolves may decrease symptoms while the transient osteoporosis resolves.
REFERENCES: Potter H, Moran M, Scheider R, et al: Magnetic resonance imaging in diagnosis of transient osteoporosis of the hip. Clin Orthop 1992;280:223-229.
Bijl M, van Leeuwen MA, van Rijswijk MH: Transient osteoporosis of the hip: Presentation of typical cases for review of the literature. Clin Exp Rheumatol 1999;17:601-604.
Montella BJ; Nunley JA, Urbaniak JR: Osteonecrosis of the femoral head associated with pregnancy: A preliminary report. J Bone Joint Surg Am 1999;81:790-798.

Question 45

0 sustained a subcapital fracture of her hip. She is an avid tennis player, and history reveals no previous fractures. What is the most appropriate follow-up care? Review Topic

Explanation

A DEXA scan is most appropriately used to establish a baseline score. Even if the bone mineral density is not within the osteoporotic range (T-score less than -2.5), a prior fragility fracture is a strong risk factor for a second fracture as a result of factors other than bone density, such as worsening vision or balance, confusion, or other predispositions to falls. The guidelines of the National Osteoporosis Foundation indicate that, following a fragility hip fracture, active anti-osteoporotic medication should be initiated, whether or not a DEXA scan is performed. A recent study showed that antiresorptive therapy following a hip fracture reduces not only the risk of a second fracture but also overall mortality.

Question 46

Synovitis of the MTP joints with eventual hyperextension deformity of the MTP is a common toe deformity seen with RA.

Explanation

Polymorphisms in the genes for the calcitonin receptor, estrogen receptor-1, vitamin D receptor, and the type I collagen alpha-1 chain (along with over 45 other genes) have been shown to be associated with osteoporosis. Answer 5, Cartilage oligomeric matrix protein, shows no current association with osteoporosis, but is the known genetic mutation associated with multiple epiphyseal dysplasia (a frequently tested fact). No single cause for osteoporosis has been shown at this point in time.
Jin et al conducted a meta-analysis regarding polymorphisms in the 5' flank of COL1A1 gene and the conflicting results relating to osteoporosis. They found that the COL1A1 Sp1 polymorphism is associated with a modest reduction in BMD and an increased risk of fracture.
The attached review by Huang and Kung discusses the multiple genetic and environmental determinants of osteoporosis and illustration A (from a different review by these same authors) lists the known genes currently associated with osteoporosis.
The greatest biomechanical difference between unicortical and bicortical locking screws is seen when what force is applied?
Compression
Torsion
Distraction
Bending on the side of the plate
Bending on the surface perpendicular to the plate
Torsion force has the largest biomechanical difference between unicortical locked screws and bicortical locked screws.
The first referenced article by Roberts et al noted that by replacing the farthest unicortical
screws (3 per side of the fracture) with bicortical locking screws, torsion resistance was increased by over 50%.
The second referenced article by Fulkerson et al noted decreased resistance to all applied forces with unicortical screws in a comminuted fracture model, and recommended against their use in such a fracture.

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You are planning surgery on a 54-year-old female with the tibial plateau fracture seen in figures A and B. After reduction of the joint surface you plan to fill the void with a bone-graft substitute to prevent joint collapse. Which of the following bone-graft substitutes
disappears most quickly in vivo?
Collagen-based matrices
Calcium phosphate
Calcium sulfate
Synthetic calcium sulfate and tri-phosphate mixture
Coraline hydroxyapatite
Calcium sulfate disappears in vivo quickly, usually within 4-12 weeks. Calcium phosphate and coraline hydroxyapatite are resorbed slowly, somewhere between 1-10 years, depending on the manufacturer. Synthetics that combine calcium sulfate and phosphate
resorb quicker than calcium phosphate but slower than calcium sulfate. Collagen-based matrices show quick resorption of the collegen but slow resorption of their hydroxyapatite coating. Walsh et al. examined the in vivo response of calcium sulfate pellets alone or in combination with autogenous bone graft in a sheep model. They found excellent bone formation in defects filled with calcium sulfate pellets. Immunostaining for various cytokines (BMP-2, BMP-7, PDGF, or TGF-beta)
showed elevated levels in the newly formed bone. They proposed that the local environment acidity was responsible for breakdown of the calcium sulfate. Watson evaluated 8 patients with comminuted tibial metaphyseal fractures treated with an injectable calcium sulfate. They found that bone regrowth was observed in all patients and the bone substitute almost completely resorbed by
months. Bucholz reviewed the biochemical, biomechanical, and longevity characteristics of the common bone substitutes.
Which of the following Figures shows a fixation construct achieving absolute stability?
Figure A shows percutaneous pinning, Figure B shows locked bridge plating, Figure C shows intramedullary nailing, Figure D shows lag fixation and neutralization plating, and Figure E shows external fixation. All except Figure D show relative stability constructs.
Absolute stability is a construct seen in Figure D, where lag screws and a neutralization plate are shown in a postoperative clavicle. No micromotion is seen with this technique, and healing is by primary (Haversian) healing, as opposed to the other four constructs, which have relative stability and heal via callus formation. The first reference, the AO Principles textbook, covers this in depth.
The second reference by Claes et al notes that bone can still heal with bone (as opposed to fibrous union) with strain rates up to 15%.
Which immunoglobulin subtype does the rheumatoid factor target?
IgA
IgE
IgM
IgG
Rheumatoid factor does not target an immunoglobulin
Rheumatoid factor is an auto-antibody most commonly seen with rheumatoid arthritis. The presence of rheumatoid factor can also indicate generalized autoimmune activity unrelated to rheumatoid arthritis (e.g. tissue or organ rejection). Rheumatoid factor is itself an IgM antibody that is directed against the Fc portion of IgG antibody. Rheumatoid factor (IgM) attaches to IgG to form immune complexes which are deposited in tissues like the kidney and contribute to the overall disease process in rheumatoid arthritis.
James et al. assessed the occurrence and predictive factors for orthopaedic surgery in an cohort of patients with rheumatoid arthritis. Risk factors for surgery varied but the authors found that decreased inflammatory markers during the first year after diagnosis decreased the risk for subsequent surgery.
The positive predictive value is defined as which of the following?
True positives / (true positives + true negatives)
False negatives / (false negatives + true positives)
False positives / (false positives + false negatives)
(True positives + false positives) / (true negatives + false negatives)
True positives / (true positives + false positives) Corrent answer: 5
The positive predictive value is defined as the true positives divided by the sum of the positive results (true positive and false positive). It is also defined as the probability that a patient with a positive test actually has the disease; it is dependent on prevalence of disease.
The referenced articles by Wojtys and Kuhn et al are two of a series of medical statistics review papers.
An 85-year-old woman undergoes the treatment seen in Figure A for a displaced left femoral neck fracture. During wound closure, the patient becomes hypoxic and hypotensive. Despite aggressive resuscitation efforts, she passes away three hours later in the intensive care unit. The autopsy findings seen in
Figure B from the patient's lungs are most likely the result of which of the following
Reaming for the femoral component
Insertion of a femoral component after cement pressurization
Utilization of undersized broaches during canal preparation
Inadequate beta blockade
Use of spinal anesthesia
The clinical scenario is consistent with fat emboli syndrome. Figure A, shows a cemented bipolar hemiarthroplasty while Figure B shows marrow embolization into the lungs.
Studies have shown that intramedullary pressure and fat embolization are greatest during pressurization of cement and implant insertion.
Intramedullary pressure is influenced by size, shape, sharpness and insertion rate of an implant. Pressurization during cementing of a femoral component generates a large degree of pressure over a much wider surface area than in the other methods described of femoral canal instrumentation or preparation, as the entire femoral canal is
pressurized at one time. This results in the highest degree of marrow embolization to the lungs resulting in hypoxia.
Dobrjanski et al studied which variables affected intramedullary pressurization and found that lower implant insertion speed, lower hammering force, a
rubber- compared with steel-tipped hammer and a larger synthetic bone-to- implant radial gap reduced intramedullary pressure generated in a femur module.
Sustained compression applied to a growth plate under experimental conditions has what effect?
No effect
Accelerated longitudinal growth
Decelerated longitudinal growth
Decelerated apposition growth
Decreased bending strength of the bone
The Heuter-Volkmann Law states that compression across the growth plate slows longitudinal growth.
Stokes et al demonstrated that sustained compression across the growth plate can decrease longitudinal growth by 40%. Tension across the physis increases growth, but to a lesser degree.
A 13-year-old girl with a displaced proximal tibia fracture is brought into the emergency department by her adult cousin. The
fracture needs surgical management. The child is living with her cousin's family while her parents are in Germany. While the child speaks fluent English, her cousin and her parents are German-only speaking. How should you consent this patient?
No consent is needed given the urgent nature of the injury, proceed with surgery
Talk with the cousin, using the child as a translator
Talk with the cousin, using a German-translator
Call the parents in Germany, using the child as a translator over the phone
Call the parents in Germany, using a German-translator over the phone
This is an urgent (not emergent) clinical senario, and as such, the child needs to have
formal consent by speaking with her parents using a German- translator.
Wenger and Lieberman discuss the problems and potential solutions surrounding the process of informed consent in patients who either personally lack capacity to make decisions or in patients who require surrogates (like minors) to make treatment decisions.
Lindseth reviews the ethical issues encountered in pediatric orthopaedics and the problems associated with these decisions. Specifically pediatric consent is confounded because the person giving the consent is not the person who will bear the consequences of the treatment.
What is the primary mode of bisphosphonate excretion?
Renal
Gastrointestinal
Liver
Skin
Pulmonary
Bisphosphonates are a broad class of medicines used to treat osteoporosis and Paget's disease. They work by inhibiting osteoclast-mediated resorption after being absorbed into the inorganic phase of bone and taken up by osteoclasts. The paper by Lin et al provides a nice review of bisphosphonates and describe their appropriate use in enhancing bone density in patients with structurally
flawed bone. They describe the mechanism of action of bisphosphonates as pyrophosphate analogues and their renal mechanism of excretion, thus, prohibiting their use in patients with renal insufficiency. Rosier discusses the role of the orthopaedic surgeon in the diagnosis and treatment of patients with osteoporosis, now referred to as the "own the bone" initiative. Central to the treatment of osteoporosis are bisphosphonates and the anti-RANKL
monoclonal antibody, Denosumab.
The 2009 AAOS Clinical Guideline on prevention of pulmonary embolism in patients undergoing total hip or knee arthroplasty recommends classifying patients as having either a "standard" or "elevated" risk of bleeding complications. The presence of all of the following qualify a patient as having an "elevated" risk of major bleeding EXCEPT?
History of hemophilia
History of protein C deficiency
History of a recent gastrointestinal bleed
History of a recent hemorrhagic stroke
History of Von Willebrand's Disease
The 2009 AAOS Clinical Guideline on prevention of pulmonary embolism in patients undergoing total hip or knee arthroplasty recommends that all patients pre-operatively should be classified as either having an elevated or standard risk of bleeding and either an elevated or standard risk of pulmonary embolism.
A history of a bleeding disorder (e.g., hemophilia, Von Willebrand's Disease), recent GI bleed, or hemorrhagic stroke qualifies a patient as having an elevated risk of major bleeding.
A history of hypercoagulable state (such as protein C deficiency) or previous documented pulmonary embolism qualifies a patient as having an elevated risk of pulmonary embolism. Type of thromboembolism prophylaxis is recommended by weighing risk of major bleeding vs risk of PE. For those patients with a known contraindication to anticoagulation an IVC filter is considered. Mechanical prophylaxis is recommended across all risk (low to
high risk of either bleeding or pulmonary embolism) groups undergoing total hip or total knee arthroplasty. The detailed AAOS guidelines can be found on the AAOS website.
The evidence based clinical recommendations are presented in the reference by Johanson et al.
In consideration of a prosthetic knee, each of the following are advantages of choosing a polycentric knee with fluid control over a constant friction knee EXCEPT:
Allows variations in cadence
Flexes in a more controlled manner
Lighter in weight
Improved stance control allows less energy expenditure
Overall length of the limb is shortened during initiation of a step reducing the risk of stumbling
Single axis, constant friction knees function as a simple hinge. They are light, durable, and much cheaper prostheses making them ideal for growing children who will need multiple prostheses before reaching adulthood. This prosthesis allows only a single speed of walking, and relies solely on alignment for stance phase stability. Polycentric knees offer each of the advantages stated above making it a more ideal prosthesis for the active adult. Disadvantages of the polycentric knee include cost, weight, and more sophisticated maintenance.
Tang et al reviews the current prosthetic options for leg and foot amputees. Illustration A demonstrates a single axis knee prosthesis.
Illustration B demonstrates a polycentric knee prosthesis.
Which of the following biologic agents commonly used to treat rheumatoid arthritis (RA) DOES NOT target tumor necrosis factor- alpha (TNF-alpha)?
Infliximab
Rituximab
Etanercept
Golimumab
Adalimumab
Rituximab is a chimeric monoclonal antibody against the protein CD20, which is primarily found on the surface of immune system B cells. Rituximab is used in combination with methotrexate to treat RA that has not responded to one or more types of treatment, including anti-tumor necrosis factor (TNF) blockers.
In rheumatoid arthritis, and other chronic inflammatory conditions, cytokines produced by activated T-cells/macrophages contribute to the pro-inflammatory state. TNF-alpha is thought to be one of the major cytokines involved in rheumatoid arthritis pathology. As a result, many biologic agents used to treat RA are directed towards blocking TNF-alpha or its receptors. These drugs are able to reduce inflammation and stop disease progression.
Elliot et al. evaluated the safety and efficacy of infliximab in 20 patients with active RA in an open phase I/II trial lasting 8 weeks. They found that treatment with anti-TNFa was safe, well tolerated and resulted in significant clinical and laboratory improvements.
Illustration A depicts five commonly used anti-TNF alpha biologic agents for the treatment of rheumatoid arhtirits with their usual dosing regimens.
Incorrect Answers:
Receptor activator of nuclear-factor kappa-B ligand (RANKL) is
an important regulator of bone resorption. Which of the following cells is the MAJOR source of RANKL in bone remodelling?
Osteoclasts
Osteoblasts
Integrins
T cells
Macrophages
RANKL, a key osteoclastogenic protein, is expressed by osteoblasts and binds to the RANK receptor on osteoclast precursor cells.
The binding of RANKL to RANK on osteoclast precursor cells drives their differentiation into mature osteoclasts (multinucleated giant cells). Mature osteoclasts bind to the bone surfaces via integrins and resorb bone via their ruffled border within Howship's lacunae. Osteocytes orchestrate bone resorption and bone deposition by controlling osteoclast and osteoblast activity. Osteoblasts release RANKL to induce osteoclast differentiation, while
osteoblasts release osteoprotegerin (OPG) to downregulate osteoclastogenesis. Osteocytes also release fibroblast growth factor-23 (FGF-23), BMPs and sclerostin to regulate osteoblast activity. Antibodies to RANKL and Sclerostin have both been shown to increase bone density.
Compton et al. reviewed osteocyte function and the emerging importance of sclerostin, which is a glycoprotein. Sclerostin is predominantly secreted by osteocytes under physiologic conditions to act as an important negative regulator of bone mass through inhibition of bone formation by osteoblasts.
Illustration A demonstrates local bone milieu. It depicts the interplay between osteocytes, osteoblasts, and osteoclasts via the factors described above.
Incorrect answers:
A 45-year-old woman with rheumatoid arthritis is being scheduled for a total knee athroplasty in 2 weeks. She is currently taking sulfasalazine, Penicillamine, and etanercept, a tumor necrosis factor inhibitor (aTNF-a). What changes should be made to her medication regimen prior to surgery?
Discontinuation of all three medications 1 weeks prior to surgery
Discontinuation of sulfasalazine 1 weeks prior to surgery, continuation of etanercept and penicillamine
Continuation of sulfasalazine, penicillamine, and etanercept
Continuation of sulfasalazine and penicillamine, discontinuation of etanercept 1 week prior to surgery
Continuation of penicillamine, discontinuation of sulfasalazine and etanercept 1 week prior to surgery
Anticytokine disease-modifying antirheumatic drugs (DMARD) have become increasingly popular in the treatment of RA. Immunosuppression and the risk of infection are potential complications for all anti-TNF-alpha medications. Current recommendations for cessation of immunosuppressive therapy are when the drug concentrations are at their lowest levels which include the following: 3 days after etanercept injection; 2 weeks prior to infliximab infusion; 10 days after adalimumab injection. Medications such as sulfasalazine and penicillamine may be continued during the pre and post- operative period. Recent evidence and guidelines such as those reviewed by Keith's paper, suggest that anti-TNF-alpha medications should be stopped 4 weeks prior to surgery.
Giles et al report in their case control series an increased infection rate of RA patients undergoing an orthopaedic procedure who were on TNF-a inhibitors as opposed to patients on more traditional treatment regimens like methotrexate and prednisone.
Which of the following supplements affects blood clotting through its effect on platelets?
Ginkgo
Vitamin D
Ephedra
St. John's Wort
Selenium
Ginkgo and ginseng are two common supplements used in the general population that have inhibitory effects of platelet function. Adverse peri- operative complications consisting of increased bleeding and hematoma formation have been reported with the use of these two herbal supplements. The most commonly used supplements that could have an effect in the peri- operative period include echinacea, ephedra, garlic, ginkgo, ginseng, kava, St John's wort, and valerian. Bleeding has been shown to be effected by garlic, ginkgo, and ginseng; cardiovascular instability from ephedra; and hypoglycemia from ginseng. Kava and valerian have pharmacodynamic herb- drug interactions that can increase the sedative effect of anesthetics. St John's wort has been shown to alter the metabolism of certain drugs used in the perioperative period.
Ang-Lee et al review common supplements used today and their potential anesthesia/operative effects. The article places emphasis on proper history taking of not only medications but also supplements which is often times left out of documentation.
The femur radiograph of a healthy 25-year-old female is compared to the femur radiograph of a healthy 85-year-old female. Which of the following best describes the 25-year-old's femur?
Increased cortical thickness and a smaller medullary canal volume
Decreased cortical thickness and a larger medullary canal volume
Equivalent cortical thickness and medullary canal volume
Increased cortical thickness and larger medullary canal volume
Decreased cortical thickness and a smaller medullary canal volume
As the human body ages the cortical thickness/area decreases and subsequently the diameter/volume of the medullary canal increases. Therefore, a young healthy 25- year-old woman should have thicker cortices and a smaller medullary canal volume than her counterpart at 85 years. A decreased cortical bone area is linked to increased fracture risk.
Stein et al studied femurs from subjects aged 21-92 years of age. They found that a reduction in cortical area was seen in older specimens and this change was more
pronounced in female specimens.
Wrong Answers:
Which of the following is NOT a described complication of corticosteroid injections?
Local flare in surrounding tissues
Apoptosis of myocytes
Skin pigmentation changes
Fat atrophy
Facial flushing
Corticosteroids have not been shown to cause apoptosis of myocytes when injected extra-articularly. Each of the other answers have been described.
Cole and Schumacher provide a review of current uses of corticosteroid injections, and emphasize that how accurately the injection is placed affects the outcome.
Kumar and Newman report prospectively on 672 patients who received 1147 intra- and extra-articular injections. Their overall complication rate was low (16%) with injection site pain (mild) and bleeding constituting the majority of cases. There were 4 instances of fat atrophy in the extra-articular group, and
cases of syncope or dizziness in the intra-articular group. They did not discuss the efficacy of their injections.
A surgeon chooses a periarticular locking plate with unicortical proximal locking screws for an extra-articular distal femur fracture as seen in Figure A. Compared to an identical construct with bicortical unlocked proximal screw fixation, the periarticular locking plate with unicortical locking screws has which biomechanical properties?
Greater torsional and axial fixation strength
Less torsional but greater axial fixation strength
Equal torsional and axial fixation strength
Greater torsional but less axial fixation strength
Less torsional and axial fixation strength
Unicortical locking plates have characteristically less torsional strength than bicortical locking plates and bicortical non-locking plates. Axial strength is improved with locking plate fixation.
Zlowodzki et al studied the LISS periarticular locking plate with unicortical proximal fixation in a distal femur model and found superior axial fixation strength (134%) but worse torsional strength (68%) compared to a fixed angle blade plate with non- locking bicortical screw fixation.
Locked plating was reviewed by Haidukewych and Ricci which highlighted the added cost, unique complications, and they recommended the use of locked plating only in situations when unlocked constructs have demonstrated poor outcomes.
In rat models looking at the effect of malnutrition on fracture healing, amino acid supplementation in a nutritionally deprived rat increases all of the following EXCEPT
Serum albumin
Body mass
Quadriceps total protein content
Fracture callus mineralization
Insulin-like growth factor 1 (IGF-1) mRNA expression
The study by Hughes et al found that essential amino acid supplementation (glutamine, arginine, and taurine) following femoral fracture in a protein- malnourished rat model increases serum albumin, body mass, quadriceps total protein content, and fracture callus mineralization. Expression of IGF-1 and
IGF-2, myosin, actin, and VEGF mRNA were all significantly decreased in the amino acid supplemented group compared to the malnourished group. The malnourished group is thought to have upregulation of mRNA expression in attempt to increase the amount of protein product that is translated, however the lack of amino acid building blocks in the malnutrition group was a barrier to appropriate protein synthesis.
The study by Day et al created a malnourished rat femur fracture model by administering a 6% protein diet. They found that administering a 20% protein diet in the post-fracture period yielded a greater cross-sectional area of the
fracture callus and callus stiffness compared to the 6% protein malnourished group.
The statistical power of a study is best defined by?
1 - probability of type-II (beta) error
True positive/(true positive + false negative)
True negative/(false positive + true negative)
1 - probability of type-I (alpha) error
[True positive/(true positive + false negative)] / false-positive rate
The power of a study is an estimate of the probability of finding a significant association in a research study when one truly exists. The power is defined by
1 - probability of type-II (beta) error, and is often set at 80%. For example, a power of 80% means that if the intervention works, the study has an 80% chance of detecting this and a 20% chance of randomly missing it. A type-II or beta error occurs when one falsely concludes that there is no significant association when there actually is an association (resulting in a false-negative study that rejects a true alternative hypothesis). The type-II or beta error can be determined if Type I error rate and sample size are known. A type-I or alpha error occurs when a significant association is found when there is no true association (resulting in a false-positive study that rejects a true null hypothesis). The alpha level refers to the probability of a type-I (alpha) error and is usually set for most studies at 0.05. Answer 2 is the formula for sensitivity. Answer 3 is the formula for specificity. Answer 5 is the formula for the positive likelihood ratio. The references by
Kocher and Wojtys are excellent reviews of basic biostatistic principles.
A 55-year-old female with a history of metastatic breast cancer develops shoulder pain without any trauma. Which of the following is involved with the findings shown in Figures A and B?
IL-4
RANK
TNF-alpha
OPG
Sox-9
Osteoclastic bone resorption is the final common mechanism for osteolysis, whether due to a pathologic lytic lesion, macrophage activation in particle wear, or normal remodeling. The RANK-RANKL mechanism controls the coupling of osteoblast and osteoclast activation. Figures A and B show an osteolytic lesion in the humerus in a patient with known metastatic breast carcinoma.
RANKL is expressed from osteoblasts and bone-marrow stromal cells. When RANKL binds to the RANK receptor (receptor/activator of NF-[kappa]B) on the cell membrane of osteoclasts it stimulates differentiation from osteoclast progenitor cells to mature osteoclasts. Mature osteoclasts proceed with osteoclastic bone resporption.
Osteoprotegerin (OPG) acts as a decoy receptor by binding to RANKL and blocking the interaction between RANKL and the RANK-receptor and consequently inhibiting osteoclast formation and
activation.
Illustration A depicts the RANK/RANKL involvement in tumor metastatic spread.
Laboratory values of a normal serum calcium and parathyroid hormone can be found in which of the following disease states?
Primary hyperparathyroidism
Type I vitamin D deficient rickets
Type II vitamin D deficient rickets
X-linked hypophosphatemic rickets
Nutritional rickets
Hypophosphatemic rickets is caused by the inability of kidney proximal tubules to reabsorb phosphate due to a mutated PHEX gene, found on the X chromosome. PHEX is thought to protect extracellular matrix glycoproteins from proteolysis. Hypophosphatemic rickets shares many clinical similarities with nutritional rickets but shows PTH levels that are not elevated, even with calcium and phosphate abnormalities.
Pettifor reviews the advances in molecular genetics in the understanding and possible treatments in tumour-induced osteomalacia/rickets.
The review article by Carpenter discusses the X-linked disorder including its clinical manifestations, the wide spectrum of disease severity, and complications of the disease in adult patients.
Illustration A is a table that details the laboratory values associated with each type of rickets.
An 80 year-old female undergoes ORIF of her hip fracture without any complications. A hospitalist consult was obtained for medical clearance pre- operatively, and she was diagnosed with osteoporosis. Which of the following treatment scenarios will lead to the best management of the patient's osteoporosis?
Schedule a follow-up appointment with the patients primary care physician to initiate therapy
Order a physical therapy consult and initiate an exercise plan
Have the patient meet with a nutritionist to increase her calcium and vitamin D intake
Start bisphosphonates, and have the patient follow-up with her primary care physician
Perform a metabolic work-up as an inpatient, and set-up an appointment in an osteoporosis clinic
The initiation of appropriate osteoporosis treatment following hip fractures occurs at a surprisingly low rate. Physical therapy and dietary changes are not appropriate initial treatments for osteoporosis, and bisphosphonate therapy should be prescribed by the physician who will be following and managing the patient's osteoporosis.
Miki et al performed a prospective randomized trial where they compared the rates of osteoporosis treatment initiation. The percentage of patients who were on pharmacologic treatment at 6 months post-injury was 58% in the group whose treatment was directed by the orthopedic surgeon and osteoporosis clinic, and 29% when managed by the primary care physician alone.
The elements chromium, molybdenum, and cobalt are basic components of which of the following implant materials?
Aluminum oxide
Cobalt alloy
Stainless steel
PMMA
Tantalum
Cobalt alloys are extremely strong and are well-suited to applications requiring longevity. Strength of the implant is improved by the addition of molybdenum. Corrosion resistance is addressed by the addition of chromium, which also increases the hardness of the implant.
Incorrect Answers:
Which of the following scenarios of treatment of a humerus fracture best achieves low strain at the fracture site and high stiffness of the treatment construct?
Functional bracing of a transverse midshaft fracture
Comminuted midshaft fracture with locked bridge plating
Short oblique fracture with interfragmentary lag screw and locked neutralization plate
Uniplane external fixation of a spiral open fracture
Oblique fracture with intramedullary nail fixation
Strain in fractures is calculated by dividing the interfragmentary movement by the size of the fracture gap. Strain must be very low (2%) for primary bone healing to occur, and should be less than 10% for secondary bone healing to occur. Stiffness refers the ability of the construct to resist movement under applied loads. Answer 3 describes a situation where primary bone healing is
the goal. For this to occur, there must be no significant gapping at the fracture site, there must be low strain between fracture fragments, and the construct must be stiff.
None of the other answers would accomplish this. Functional bracing and intramedullary fixation both accomplish healing through formation of fracture callus, or secondary healing. A comminuted fracture treated with locked bridge plating relies on less stiffness to allow for secondary healing between fragments. However, since there are many fracture fragments, the strain is distributed among them and therefore remains low. A uniplane external fixator is very unlikely to accomplish low strain and high stiffness in this setting.
A 67-year-old man complains of low-grade fevers and calf pain 2 weeks following a total knee arthroplasty. What is the next appropriate step in management of this patient?
Plethysmography of lower extremity
MRI of lower extremity
CT angiography of lower extremity
Venous ultrasonography
Knee aspiration to evaluate for septic joint
Venous ultrasonography is the next best step in this patient's management, due to the clinical picture of a deep venous thrombosis. The most sensitive and specific recommended diagnostic procedure is a venous ultrasonography.
In their multi-center study, Haut et al. hypothesized that admission to trauma centers that use duplex ultrasound more frequently would independently predict increased DVT reporting for individual patients. They indeed found that trauma centers ultrasound practice was an independent predictor of DVT diagnosis for individual patients, controlling for patient-level risk factors, but concluded the elevated DVT rates at these centers were due to surveillance bias. As such, they recommend that surveillance for DVT should not be considered as a quality control measure in the care of trauma patients.
A patient undergoes closed reduction of a bimalleolar ankle fracture dislocation by the ER physician and is sent to your clinic for evaluation. You evaluate the patient and schedule him for surgery. According to the 2009 guidelines, which of the following scenarios would meet criteria for coding the encounter as a new patient?
You injected his knee in the office almost 3 years ago for osteoarthritis, and have not seen him since
He had an arthroscopic operation by your partner 4 years ago
You were consulted 1 year ago for shoulder pain when he was hospitalized for chronic renal failure
He was seen by your partner in clinic for a herniated disk 2 years ago, but had no procedures performed
You performed a hip replacement on him 12 years ago, and his last follow- up was 18 months ago at which time he was doing well
Only answer two is correct. The 2009 guidlines clarify that the patient can be defined as new only if he has not been seen by anyone in the physician's same group practice and of the same specialty in the past 3 years. Hand and sports medicine specialists with a CAQ, however, are an exception and are allowed to bill for patients already seen by other orthopedists in the same group as new
patients. This scenario would not qualify as a consultation, since the orthopedic surgeon
is taking over care of the patient's problem and is not merely offering advice to another physician who is already caring for the patient. Consultations do not have the same 3 year time qualification. However, Medicare and many other insurers no longer recognize consultation codes.
All the following medications binds reversibly to the enzyme COX-1 EXCEPT
Meloxicam
Diclofenac
Indomethacin
Naproxen sodium
Aspirin
Aspirin binds irreversibly to the cyclooxygenase enzyme. Aspirin acetylates platelet cyclooxygenase and permanently inhibits thromboxane (TX) A2 production leading to its antiplatelet effects. The other NSAID's listed above bind reversibly with COX-1.
Patrono et al discuss the pharmokinetics and platelet effect of both low dose and regular dose aspirin. Nonsteroidal anti-inflammatory drugs compete dose- dependently with arachidonate for binding to platelet cyclooxygenase.
In the treatment of patients with rheumatoid arthritis, TNF-alpha is blocked by which of the following agents?
Tocilizumab
Anakinra
Etanercept
Abatacept
Rituximab
Etanercept is a biochemically designed soluble p75 tumor necrosis factor receptor immunoglobulin G fusion protein, which blocks the downstream
effects of TNF.
Methotrexate is a chemotherapy agent used to inhibit lymphocytes. Gold inhibits monocytes, while sulfasalazine is an anti-inflammatory decreasing the production of
prostaglandins and leukotrienes. Rituximab inhibits B-cells as it
is a monoclonal antibody to CD20 antigen. Anakinra (Kineret) is a recombinant IL-1 receptor antagonist. Abatacept (Orencia) is a selective costimulation modulator that binds to CD-80 and CD-86 (inhibits T cells). Tocilizumab (Actemra)is an IL-6 receptor inhibitor (2nd line treatment for poor response to TNF-antagonist therapy).
Pisetsky wrote an editorial in NEJM discussing the development of TNF blockers through research, and the potential for the use of Etanercept in patients with juvenile RA through its inhibition of lymphotoxin-alpha.
Which of the following medications when combined with methotrexate has been shown to be more effective than methotrexate alone in the treatment of rheumatoid arthritis?
Nitrofurantoin
Rifampin
Azithromycin
Erythromycin
Doxycycline
Tetracycline was initially used in the treatment of rheumatoid arthritis (RA) because Mycoplasma was thought to be the causative agent. It was later found that tetracyclines have biologic effects on the inflammatory and immunologic cascade by inhibiting collagenase activity. Collagenase is an enzyme involved
in breaking down macromolecules in the connective tissue, contributing to the pathologic changes of RA.
In a prospective study, O'Dell et al found that initial therapy with methotrexate plus doxycycline was superior to treatment with methotrexate alone. Furthermore, similar results for low-dose and high-dose doxycycline suggested that antimetalloproteinase effects were more important than the antibacterial effects.
When using C-arm fluorocopy, patient radiation exposure will be increased with which of the following?
The extremity is positioned closer to the image intensifier
A larger body part is imaged compared to a smaller body part
Use of radiation beam collimation
Mini C-arm fluroscopy is used instead of large C-arm fluroscopy
Decreased duration of imaging
Patient radiation exposure will be increased if a larger body part is imaged compared to a smaller body part.
The first study by Giordano et al used radiation dosimeters for large and mini c-arm machines. They found that elevated exposure levels can be expected when larger body parts are imaged, when the extremity is positioned closer to the x-ray source, and when the large c-arm is used over the mini c-arm.
The second study by Giordano et al also used dosimeters for a mini c-arm and found that the surgical team is exposed to minimal radiation during routine
use of mini-c-arm fluoroscopy, except when they are in the direct path of the radiation beam. They list factors to decrease radiation exposure to patient and surgeon including: minimizing exposure time, reducing exposure factors, manipulating the x-ray beam with collimation, orienting the fluoroscopic beam in an inverted position relative to the patient, strategic positioning of the surgeon within the operative field, judicious use of protective shielding during imaging, and maximizing the distance of the surgeon from the radiation beam.
Illustration A shows that arrangement #1 has the body part half-way between the radiation source and image intensifier. Arrangement #2 has the the image intensifier acting as an arm table for the body part with the radiation source further away. Arrangement #1 has more radiation exposure than #2. The distance between the x-ray tube and the body part is doubled in arrangement
#2 compared to arrangement #1. This increased distance correlates to a reduction in exposure according to the inverse square law (reduction in radiation intensity with greater distance from the x-ray source).
You are seeing a 13-year-old girl for asymptomatic flat feet and recommend observation. In educating this patient/family about general bone health, you recommend what amount of daily dietary calcium for your patient?

Question 47

When discussing treatment options with a 35 year-old healthy male with an isolated, closed tibial shaft fracture, the surgeon should inform him that in comparison to closed treatment, the advantages of intramedullary nail fixation include all of the following EXCCEPT?

Explanation

DISCUSSION: All of the answer choices are correct except #3. Intramedullary nailing can increase the risk of compartment syndrome.
In a study of 94 tibial fractures, Finkemeier reported 10 (11%) had compartment syndromes. Three of the 10 patients developed the compartment syndrome postoperatively.
In comparing IM nailing to non-op, Bone et al showed that IM nailing had a shorter time to union (mean, 18 vs 26 weeks; p = 0.02), lower non-union rate (2% vs 10%), decresed incidence of shortening (2% vs 27%), and quicker return to work (mean, 4 vs 6.5 months), but no difference in compartment syndrome (0% in both groups).
The classic article cited by Sarmiento el al. reported that closed treatment with use of a prefabricated functional below-the-knee brace was effective in a study of 1000 closed diaphyseal fractures of the tibia with an incidence of nonunion of only 1.1%. However, those authors had very strict criteria for use of the fracture-brace (exclusion criteria included intact fibular, shortening >2cm).

Question 48

Figure 5 shows the radiograph of a 10-year-old girl who reports chronic shoulder pain after her gymnastics classes. Examination reveals pain on internal and external rotation but no instability. What is the most likely diagnosis?

Explanation

DISCUSSION: The patient has a very wide humeral growth plate, indicating the presence of a proximal humeral stress fracture, an uncommon diagnosis in gymnasts. Gymnasts are prone to stress fractures of the scaphoid, distal radius, elbow, and clavicle. Proximal humeral stress fractures are more commonly seen in those participating in racket or throwing sports. Stress fractures can lead to growth arrest or inhibition, particularly in the distal radius. The radiograph shows normal findings for the acromion, acromioclavicular joint, scapula, and triceps origin.
REFERENCES: Fallon KE, Fricker PA: Stress fracture of the clavicle in a young female gymnast. Br J Sports Med 2001;35:448-449.
Sinha AK, Kaeding CC, Wadley GM: Upper extremity stress fractures in athletes: Clinical features of 44 cases. Clin J Sports Med 1999;9:199-202.
Caine D, Howe W, Ross W, Bergman G: Does repetitive physical loading inhibit radial growth in female gymnasts? Clin J Sports Med 1997;7:302-308.
Chan D, Aldridge MJ, Maffulli N, Davies AM: Chronic stress injuries of the elbow in young gymnasts. Br J Radiol 1991;64:1113-1118.

Question 49

A 25-year-old woman has had pain and stiffness in her knee following a motor vehicle accident 9 months ago. The radiograph, CT scan, MRI scan, and biopsy specimen are shown in Figures 53a through 53d. What is the most likely diagnosis?

Explanation

DISCUSSION: Heterotopic ossification may occur spontaneously or following trauma. The imaging studies and histology reveal mature fatty bone marrow and trabecular bone. Osteochondromas are cortically based with the medullary canal extending into the lesion. This is not evident in this patient. Also, no obvious cartilage cap is present. Parosteal osteosarcoma commonly occurs in the posterior distal femoral cortex but is ruled out by the lack of the typical fibrous stromal cells forming the low-grade malignant osteoid. The histology and clinical presentation eliminate osteomyelitis and osteoblastoma.
REFERENCES: Horne LT, Blue BA: Intra-articular heterotopic ossification in the knee following intramedullary nailing of the fractured femur using a retrograde method. J Orthop Trauma 1999;13:385-388.
Stannard JP, Wilson TC, Sheils TM, McGwin G Jr, Volgas DA, Alonso JE: Heterotopic ossification associated with knee dislocation. Arthroscopy 2002;18:835-839.
Mills WJ, Tejwani N: Heterotopic ossification after knee dislocation: The predictive value of the injury severity score. J Orthop Trauma 2003;17:338-345.

Question 50

A 17-year-old high school football player sustains a neck injury in a game. During the initial on-field assessment, the team physician removes his helmet, and the athlete is log-rolled to the supine position while the physician manually stabilizes his cervical spine. An examination demonstrates tenderness to palpation over the cervical spine and neurologic deficits in bilateral upper and lower extremities. Shoulder pads prohibit proper placement of a hard cervical collar, and the athlete is immobilized on a spine board and transported to the emergency department via ambulance. Comprehensive evaluation in the emergency department reveals a bilateral facet dislocation of C5 on C6. The on-field intervention most likely to cause a neurologic injury is

Explanation

DISCUSSION
Complete immobilization of the cervical spine is critical for athletes with a suspected cervical spine or spinal cord injury. The spinal cord in the subaxial spine is especially sensitive to motion, and removal of protective gear such as the helmet and shoulder pads presents an unacceptable risk for progressive neurologic injury in the setting of a potentially unstable cervical spine injury. Removal of the face mask alone is typically performed to improve access to an athlete's airway. Protective equipment often prevents proper placement of a hard cervical collar, and the spine board offers a variety of options for safe cervical spine immobilization of helmeted athletes without a hard cervical collar. The log-roll and lift-and-slide techniques
allow for the safe transfer of an athlete to a spine board while maintaining appropriate manual stabilization of the cervical spine.

Question 51

A 36-year-old recreational tennis player sustains the injury shown in Figure 16. Management should consist of

Explanation

DISCUSSION: The MRI scan shows a rupture of the patellar tendon. This injury is most appropriately addressed with primary repair. For athletic individuals, the results of nonsurgical management are suboptimal. Reconstructive procedures are not necessary.
REFERENCES: Matava MJ: Patellar tendon ruptures. J Am Acad Orthop Surg 1996;4:287-296.
Marder RA, Timmerman LA: Primary repair of patellar tendon rupture without augmentation. Am J Sports Med 1999;27:304-307.

Question 52

The use of nonsteroidal anti-inflammatory drugs following femoral nailing has been associated with which of the following?

Explanation

DISCUSSION: The risk of femoral nonunion after intramedullary nailing is significantly increased when NSAIDs are administered post-operatively.
Giannoudis et al assessed factors which could affect union in 32 patients with nonunion of a fracture of the diaphysis of the femur and 67 matched patients whose fracture had united. They found that there was no relationship between the rate of union and the type of implant, mode of locking, reaming, distraction or smoking. They also concluded that there was a marked association between nonunion and the use of NSAIDs after injury and delayed healing was noted in patients who took NSAIDs and whose fractures had united.
Burd et al performed a study to determine if patients with an acetabular fracture, who received indomethacin for prophylaxis against HO, were at risk of delayed healing or nonunion of any associated fractures of long bones. The study group consisted of 112 patients who had sustained at least one concomitant fracture of a long bone; of which 36 needed no prophylaxis, 38 received focal radiation and 38 received indomethacin. When comparing patients who received indomethacin with those who did not, a significant difference was noted in the rate of long bone nonunion (26% vs 7%).

Question 53

A 12-year-old girl is seen for left ankle pain. Radiographs reveal osteochondritis dissecans (OCD) involving the talus. What should the parents be told regarding management?

Explanation

DISCUSSION: Nonsurgical management of OCD of the talus in skeletally immature individuals frequently results in a fairly rapid decrease in symptoms, but radiographic abnormalities can frequently be found even 6 months after treatment. Spontaneous resolution of this condition is rare. Hyperbaric oxygen treatment has not been shown to be beneficial for this condition. Progression of the condition to the point of requiring ankle fusion is rare.
REFERENCES: Perumal V, Wall E, Babekir N: Juvenile osteochondritis dissecans of the talus. J Pediat Orthop 2007;27:821-825.
Letts M, Davidson D, Ahmer A: Osteochondritis dissecans of the talus in children. J Pediatr Orthop 2003;23:617-625.

Question 54

The injection shown in Figures 1a and 1b would most benefit a patient who reports which of the following symptoms? Review Topic

Explanation

The images demonstrate a L5 selective root block as it exits the L5-S1 foramen. This root block best helps relieve pain or paresthesias in the L5 distribution, which is the dorsal first web space and the great toe. The lateral foot is an S1 distribution and would need to be blocked through the posterior first sacral foramen. The anterior shin and thigh represent the L4 root which exits a level above this at the L4-5 foramen. A stocking distribution is nonanatomic and not indicative of a specific root.

Question 55

The parents of a 14-year-old female soccer player are concerned about any future injury. They have been advised that she has the potential to play for the US Olympic team. They are especially concerned about the anterior cruciate ligament (ACL). What should you advise them?

Explanation

DISCUSSION: ACL injuries are five to eight times more common in young women. The highest incidence is associated with basketball and soccer. These sports require rapid directional and rotational changes. Use of neuromuscular training programs has not been associated with a decrease in ACL injuries. It is recommended that there be more frequent rests. ACL injuries are commonly associated with meniscal injury.
REFERENCES: Shea KG: ACL Injury: Epidemiology and Prevention Presented at Sports Related Injuries in the Skeletally Mature Athlete. POSNA: One Day Course, 2008.
Millett PJ, Willis AA, Warren RF: Associated injuries in pediatric and adolescent anterior cruciate
ligament tears: Does a delay in treatment increase the risk of meniscal tears? Arthroscopy 2002; 18:955-959.

Question 56

A 19-year-old woman fell onto her nondominant hand 6 weeks ago. Radiographs are shown in Figures 37a and 37b. A decision has been made to treat this fracture surgically. What is the best approach to treat this fracture?

Explanation

DISCUSSION: Displaced fractures of the scaphoid are best treated with compression screw fixation. Proximal third fractures (as in this patient) are optimally approached via a dorsal approach to ensure proper reduction and compression. Fractures of the scaphoid waist can be approached either by a volar or a dorsal approach. Kirschner wire fixation is limited to proximal pole fractures that are too small to accommodate the trailing head of a compression screw.
REFERENCES: Retting ME, Raskin KB: Retrograde compression screw fixation of acute proximal pole fractures. J Hand Surg Am 1999;24:1206-1210.
Filan SK, Herbert TJ: Herbert screw fixation of scaphoid fractures. J Bone Joint Surg Br 1996;78:519-529.

Question 57

A 37-year-old man has left shoulder pain and weakness. Coronal T1- and axial T2-weighted MRI scans are shown in Figures 17a and 17b. The biopsy specimen is shown in Figure 17c. What is the most likely diagnosis?

Explanation

DISCUSSION: A ganglion cyst arising from the posterior labrum of the shoulder is a known cause of suprascapular nerve impingement. The MRI characteristics of low-signal intensity on T1 and high-signal intensity on T2 are seen in lesions with a high fluid content. The histology shows a cavity with a thin fibrous lining.
REFERENCES: Ferrick MR, Marzo JM: Suprascapular entrapment neuropathy and ganglion cysts about the shoulder. Orthopedics 1999;22:430-434.
Post M: Diagnosis and treatment of suprascapular nerve entrapment. Clin Orthop 1999;368:92-100.

Question 58

A 63-year-old man with type I diabetes mellitus who underwent open forefoot amputation now has a high fever, and an elevated WBC count and blood glucose levels. Repeat laboratory studies the day after surgery show a WBC count of 9,500/mm 3 , a serum albumin level of 1.9 g/dL, and a total lymphocyte count of 1,900/mm 3 . Examination reveals that he is afebrile, and his blood glucose level is now normal. An ultrasound Doppler of the dorsalis pedis artery shows an ankle-brachial index of 0.6. A transcutaneous partial pressure measurement of oxygen at the ankle joint shows a level of 38 mm Hg. What is the best course of action?

Explanation

DISCUSSION: This patient appears to have adequate blood supply to heal a Syme’s ankle disarticulation but is currently malnourished because of the systemic infection, and is likely to progress to wound failure. Therefore, the initial management of choice is culture-specific antibiotic therapy, open wound management, and nutritional supplementation. If his serum albumin rises to a minimum of 2.5 gm/dL, he can undergo elective Syme’s ankle disarticulation. If the serum albumin does not rise within a short period of time, he should undergo transtibial amputation.
REFERENCE: Pinzur MS, Stuck RM, Sage R, et al: Syme ankle disarticulation in patients with diabetes. J Bone Joint Surg Am 2003;85:1667-1672.

Question 59

During a posterior cruciate ligament-sacrificing total knee arthroplasty with anterior referencing, 8 mm of distal femur is resected. It is noted that the flexion gap is tight and the extension gap appears stable. What is the next most appropriate step in management?

Explanation

DISCUSSION: If the flexion gap is tight and the extension gap is correct, it is preferable to change only the flexion gap and leave the extension gap unchanged; therefore, the treatment of choice is to decrease the size of the femoral component. The smaller component will be smaller in both medial-lateral as well as anterior-posterior dimensions. A smaller anterior-posterior size will allow more space for the flexion gap without significantly affecting the extension gap. Decreasing the size of the tibial polyethylene insert thickness or cutting more proximal tibia will affect both the flexion and extension gaps. Cutting more distal femur will increase the extension gap and not change the flexion gap, making the described situation worse. Cutting both the proximal tibia and distal femur will increase both the flexion and extension gaps.
REFERENCE: Pellicci PM, Tria AJ Jr, Garvin KL (eds): Orthopaedic Knowledge Update: Hip and Knee Reconstruction 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000, pp 281-286, 339-365.

Question 60

A 2-year-old boy has complete absence of the sacrum and lower lumbar spine. What is the most likely long-term outcome if no spinal pelvic stabilization is performed?

Explanation

DISCUSSION: Without stabilization, progressive kyphosis will develop between the spine and pelvis. The kyphosis progresses to the point that the child must use his or her hands to support the trunk, and therefore is unable to use his or her hands for other activities. Neck extension contracture does not usually develop. Neurologic deficit, including sexual dysfunction, is generally present at birth and static.
REFERENCES: Tachdjian MO: The spine: Congenital absence of the sacrum and lumbosacral vertebrae (lumbosacral agenesis), in Wickland EH Jr (ed): Pediatric Orthopaedics, ed 2. Philadelphia, PA, WB Saunders, 1990, vol 3, p 2228.
Renshaw TS: Sacral agenesis: A classification and review of twenty-three cases. J Bone Joint Surg Am 1978;60:373-383.

Question 61

Which of the following is considered the most accurate test to determine the amount of limb-length discrepancy in a patient with a knee flexion contracture of 35°?

Explanation

DISCUSSION: Flexion contractures and angular deformities of a limb cause inaccurate limb-length measurement results with most clinical methods. A CT scanogram is more accurate than standard scanograms for determining limb length in patients with knee flexion contractures of 30° or more. The cost and time necessary to complete the examinations are comparable, but the CT scanogram delivers only 20% of the radiation needed for standard scanograms.
REFERENCES: Aaron A, Weinstein D, Thickman D, Eilert R: Comparison of orthoroentgenography and computed tomography in the measurement of limb-length discrepancy. J Bone Joint Surg Am 1992;74:897-902.
Tachdjian MO: Pediatric Orthopedics. Philadelphia, Pa, WB Saunders, 1990, pp 2867-2870.

Question 62

A 10-year-old boy who plays baseball reports acute pain after throwing a softball from the outfield to second base. A radiograph is shown in Figure 26. Management should consist of

Explanation

DISCUSSION: The patient has a fracture through a unicameral bone cyst, as evidenced by the “falling leaf” sign on the radiograph. Following healing of the fracture, treatment should consist of corticosteroid injection or bone marrow injection. Some cysts heal with the fracture and do not require injections. Biopsy is unnecessary because the radiograph shows that the cyst is benign. Curettage and bone grafting are seldom necessary because these cysts regularly heal with injections. Corticosteroids are useful when injected into the cyst, but are not used systemically. Pulsed electromagnetic fields have not been used therapeutically in this condition.
REFERENCE: Yandow SM, Lundeen GA, Scott SM, Coffin C: Autogenic bone marrow injections as a treatment for simple bone cyst. J Pediatr Orthop 1998;18:616-620.

Question 63

Use of titanium elastic nailing for treatment of pediatric femur fractures is associated with a higher complication rate among

Explanation

DISCUSSION
Studies of titanium elastic nailing for femur fractures demonstrated a higher rate of complications, including angular deformity and construct failure, among patients weighing more than 50 kg (100 pounds). Other methods of fixation are recommended for these patients. Flexible nails are not commonly needed, but they also are not associated with a higher complication rate in children younger than age 6.5. Titanium elastic nailing works well in closed or minimally open transverse midshaft fractures, even in the setting of early or immediate weight bearing.

Video 8a
Video 8b

Question 64

The histology of the lesion is shown in Figure 101d. What is the most likely complication after treatment of this lesion?

Explanation

DISCUSSION FOR QUESTIONS 101 THROUGH 103:
The MRI scans show a well-circumscribed inhomogenous mass at the anterior ankle joint consistent with a diagnosis of pigmented villonodular synovitis (PVNS), not an anatomic variant. An inflammatory mass,such as the pannus of rheumatoid arthritis, would reveal moderate signal intensity with relatively uniform signal throughout. The mass is well encapsulated, respecting tissue boundaries and not showing invasive characteristics as malignancies would. The arthroscopic image is also consistent with the reddish-brown frond-like tissue of PVNS. PVNS of the ankle can be treated arthroscopically. If this mode of treatment is chosen, a tissue sample should be sent to pathology for microscopic analysis; débridement should be performed on the remaining tissue. Removal of the instrumentation without débridement will not provide treatment and will result in disease progression. Tourniquet placement does not provide therapeutic benefit.
Brachytherapy has not been described for the treatment of PVNS of the ankle. The histologic image shows multiple multinucleated giant cells, hemosiderin, and very few mitotic figures – consistent with a diagnosis of PVNS. A common complication of PVNS treatment is local recurrence. Arthrofibrosis and chondrolysis are not seen with proper surgical care of these patients. Because this is not an infectious lesion, disseminated infection after treatment is highly unlikely. PVNS rarely metastasizes.
RESPONSES FOR QUESTIONS 104 THROUGH 106
Toe is fused too straight (plantar flexed)
Toe is fused in too much valgus
Toe is fused in too much dorsiflexion
There is a nonunion of the fusion
Excessive shortening of the first metatarsal during preparation for fusion What is the most likely diagnosis for each patient?

Question 65

A 58-year-old woman underwent a left total knee arthroplasty 6 years ago. She initially did well after surgery but sustained a fall 2 months ago while at work. She now describes left knee pain and instability and an inability to straighten her knee since the fall. She has been using a hinged knee brace, which provides partial support. On examination, she has passive range of motion of 0° to 115° and active range of motion of 80° to -115°. Her radiographs are shown in Figures below. What is the best option for the restoration of her function?

Explanation

DISCUSSION:
The patient has an extensor mechanism disruption with patellar tendon rupture. This injury is treated with extensor mechanism reconstruction in the setting of previous total knee arthroplasty. There is a reported high failure rate with attempted repair. Revision to hinge knee arthroplasty would provide implant stability but would not restore the extensor mechanism. The patient is relatively young and is working, so reconstruction would offer better long-term function than a drop lock brace, which can be better used in low-functioning patients with this type of injury. Extensor mechanism reconstruction historically has been accomplished with allograft material, but a novel technique using synthetic mesh also has proved successful in treating this difficult problem.

Question 66

A 39-year-old man presents with back pain radiating to the left lower extremity for the past 6 weeks. Magnetic resonance images of the pathology are

Explanation

The patient presents with MRI suggestive of far lateral disc herniation at the L3-L4 disc space. He would be expected to have symptoms in L3 nerve distribution, near the medial epicondyle of the femur. Associated motor manifestations may include quadriceps weakness and/or diminished patellar reflex.
Far lateral disc herniations constitute approximately 5-10 percent of disc hernations in the lumbar spine. Given the more vertical anatomy of lumbar nerve roots, at a given disc level, a central or paracentral herniation will affect the traversing nerve root (e.g. nerve root of level below) and a far lateral herniation will affect the exiting nerve root (e.g. nerve root of the level above). Similar to the more common central and paracentral herniations, approximately 90% of patients will improve without surgical intervention. When surgical intervention is needed, the paraspinal approach of Wiltse is utilized.
Marquadt et al. reported long term outcomes of surgical management of far lateral disc herniations. At an average of 146 months follow up, 56.3% of patients had complete relief of symptoms and 27.6% had permanent residual symptoms. Over 75% of patients subjectively rated their outcomes as excellent.
Figure A and B are T2 and T1 axial MRI images, respectively, showing the L3-L4 disc space with a left far lateral disc herniation. Figure C is a left parasagittal T2 MRI image showing impingement on the L3 nerve root. Structures are labeled in illustration A. Illustration B shows the dermatomes of the lower extremity.
Incorrect Answers:

Question 67

A 34-year-old man underwent a transtibial amputation as the result of a work-related injury. The amputation was performed at the inferior level of the tibial tubercle. The residual limb has a soft-tissue envelope composed of gastrocnemius muscle that is used as soft-tissue cushioning for the distal tibia. Despite undergoing several prosthetic fittings, he continues to report pain and instability. Examination reveals that the prosthesis appears to fit well with no apparent pressure points or areas of skin breakdown. He is not willing to have any further surgery. Which of the following modifications will most likely provide relief?

Explanation

DISCUSSION: While transtibial amputees can be fitted with a prosthesis with a residual limb as short as 5 cm, or with retention of the insertion of the patellar tendon, this patient has an unstable gait because of the limited ability of the prosthetic socket to maintain a snug and stable fit. While cumbersome and bulky, double metal uprights and a corset is the only predictable method of gaining stability. The other methods attempt to add an element of stability; however, they are unlikely to be successful.
REFERENCES: Bowker JH, Goldberg B, Poonekar PD: Transtibial amputation: Surgical procedures and postsurgical management, in Bowker JH, Michael JW (eds): Atlas of Limb Prosthetics. St Louis, MO, Mosby Year Book, 1992, pp 429-452.
Kapp S, Cummings D: Transtibial amputation: Prosthetic management, in Bowker JH, Michael JW (eds): Atlas of Limb Prosthetics. St Louis, MO, Mosby Year Book, 1992, pp 453-478.

Question 68

A 62-year-old man slips on ice and sustains an elbow dislocation. Post-reduction imaging reveals a highly comminuted radial head fracture and coronoid fracture through its base. What is the most appropriate treatment?

Explanation

DISCUSSION: The results of elbow dislocations with associated radial head and coronoid fractures are often poor because of recurrent instability and/or stiffness from prolonged immobilization. Therefore radial head replacement and open reduction internal fixation of the coronoid is the most appropriate treatment.
Pugh et al reported their experiences with this difficult population. Their protocol consisted of ORIF or replacement of the radial head, ORIF of the coronoid fracture, repair of the LCL and capsule, and repair of the MCL and/or hinged external fixation. Of the 36 cases, the outcome was graded as 28 excellent to good, 7 fair, and 1 poor. 8 cases required re-operation. The authors concluded that their surgical protocol restored sufficient elbow stability to allow early motion post-op, thereby enhancing the functional outcome. In fracture dislocation of the elbow with radial head
and coronoid fracture, the radial head must be fixed or replaced to restore stability. The ORIF of coronoid fracture and radial head restores some valgus stability therefore MCL repair may not be needed. However, the varus stability must be restored by LCL repair.

Question 69

An 83-year-old woman with a long history of her foot slowly and progressively “turning out” now reports significant ankle pain. History reveals that she has significant cardiac disease and exercise-induced angina. Examination reveals a deficiency in the posterior tibial tendon; however, the hindfoot remains moderately supple. Radiographs reveal a valgus tilt of the tibiotalar joint and early arthrosis. What is the most appropriate orthotic management?

Explanation

DISCUSSION: The patient will continue to have pain secondary to the ankle arthrosis with both the UCBL and the molded articulated ankle-foot orthosis. The total contact orthotic does not provide enough hindfoot control to support the progressive collapse of the ankle into valgus positioning. A molded leather gauntlet will not only control tibiotalar motion but also control hindfoot motion and allow support of the longitudinal arch.
REFERENCE: Augustin JF, Lin SS, Berberian WS, et al: Nonoperative treatment of adult acquired flat foot with the Arizona brace. Foot Ankle Clin 2003;8:491-502.

Question 70

Which of the following is associated with the use of large femoral heads in total hip arthroplasty?

Explanation

DISCUSSION: Larger diameter femoral heads reduce the risk of hip dislocation by allowing greater range of motion before component impingement becomes a risk, and no reports have shown an increase in bearing wear. With modem bearings, volumetric wear should remain low, despite the increase in head diameter. Large femoral heads are available in all common bearing materials
REFERENCES: Peters CL, McPherson E, Jackson JD, et al: Reduction in early dislocation rate with large-diameter femoral heads in primary total hip arthroplasty. J Arthroplasty 2007;22:140-144.
Inoue A, Asaumi K, Endo H, et al: Assessment of head wear more than ten years after total hip arthroplasty: 22- mm zirconia vs metal heads. Acta Med Okayama 2006;60:311-318.

Question 71

A year-old man who underwent right total knee replacement surgery 2 and a half years ago has had knee pain since surgery. The pain is diffuse, constant, and made worse with activity. He notes warmth and swelling in his knee. Examination shows a well-healed incision, no erythema, moderate warmth, synovitis, and an effusion. The knee is stable, and has an arc of flexion between 3° and 120°. Radiographs show well-fixed and well-aligned implants. What is the most appropriate initial treatment?

Explanation

DISCUSSION:
This patient's history and physical findings are concerning for deep infection. Inflammatory markers, including ESR and CRP, should be obtained first. If the levels are elevated, knee aspiration should be performed for the synovial cell count and culture. A bone scan is not indicated in an initial investigation for deep infection; it is rarely helpful and is not cost effective. CT to assess implant rotation is an appropriate investigation for knee pain when the clinical scenario is not suspicious for a deep infection
and when infection has been excluded.

Question 72

Avascular necrosis

Explanation

Slide
A 9-year-old girl sustains an injury (Slide) as a result of a fall. What is her risk of avascular necrosis:

Question 73

Figure 10 shows the radiograph of an 18-year-old woman who sustained a spinal cord injury in a motor vehicle accident. Based on the radiographic findings, her injury is best described as

Explanation

DISCUSSION: The Allen and Ferguson mechanistic classification system is a useful tool for evaluating cervical spine injuries. Cervical fractures are classified as compressive extension, distractive extension, compressive flexion, distractive flexion, vertical compression, and lateral flexion. The patient has a distractive flexion injury.
REFERENCE: Allen BL Jr, Ferguson RL, Lehmann TR, O’Brien RP: A mechanistic classification of closed, indirect fractures and dislocations of the lower cervical spine. Spine 1982;7:1-27.

Question 74

03 Which of the following findings is one of the diagnostic criteria for diffuse idiopathic skeletal hyperostosis?

Explanation

back answer
Diffuse idiopathic skeletal hyperostosis is a common disease, most prevalent in those over 50 years of age. The usual presentation is a middle-aged or older patient with chronic mild pain in the middle to lower back, spinal stiffness, and typical radiographic changes in the thoracic spine. Diffuse idiopathic skeletal hyperostosis is predominantly a radiographic diagnosis with 3 major diagnostic criteria. 1. Flowing ossification along the anterolateral aspect of at least four contiguous vertebrae. 2. Preservation of disk height in the involved vertebral segment; the relative absence of significant degenterative changes, such as marginal sclerosis in vertebral bodies or vacuum phenomenon. 3.
Absence of facet-joint ankylosis; absence of sacroiliac erosion, sclerosis, or intra-articular osseous fusion. Treatment is typically non-operative, with anti-inflammatories, activity modification and PT.
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Question 75

Why is tendon considered an anisotropic material?

Explanation

DISCUSSION: Anisotropic materials have mechanical properties that vary based on the direction of loading. The relative values of Young’s modulus for tendon, ligament, and bone are not relevant to isotropy. The mechanical properties of tendon do change with preconditioning, but this change is related to viscoelasticity. The intrinsic mechanical properties of tendon do vary with the rate of loading, but this variance is related to viscoelasticity.
REFERENCES: Buckwalter JA, Einhorn TA, Simon SR (eds): Orthopaedic Basic Science: Biology and Biomechanics of the Musculoskeletal System, ed 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000, pp 134-180.
Lu L, Kaufman KR, Yaszemski MJ: Biomechanics, in Einhorn TA, O’Keefe RJ,

Buckwalter JA (eds): Orthopaedic Basic Science: Foundations of Clinical Practice, ed 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, in press.

Question 76

A large circumferential proximal femoral allograft is to be used in the reconstruction of a failed femoral component in a total hip arthroplasty. To enhance fixation of the graft to the implant, which of the following strategies should be used?

Explanation

DISCUSSION: The optimum treatment is cementing the implant to the allograft. Press-fit stability is unreliable. Wires and screws may be used for an incomplete proximal femoral allograft but cannot be used to anchor a complete proximal femoral allograft.
REFERENCES: Allan DG, Lavoie GJ, Rudan JF, et al: The use of allograft bone in revision total hip arthroplasty, in Friedlaender GE, Goldberg VM (eds): Bone and Cartilage Allografts: Biology and Clinical Applications. Park Ridge, IL, American Academy of Orthopaedic Surgeons, 1991, pp 263-264.
Gross AE, Lavoie MV, McDermott P, Marks P: The use of allograft bone in revision of total hip arthroplasty. Clin Orthop 1985;197:115-122.
Head WC, Berklacich FM, Malinin TI, Emerson RH Jr: Proximal femoral allografts in revision total hip arthroplasty. Clin Orthop 1987;225:22-36.

Question 77

A resident arrives to the operating room late for a LEFT carpal tunnel release procedure. The patient is prepped and draped under general anaesthesia, and the attending surgeon and assistant are about to make an incision to the RIGHT carpal tunnel. The resident mentions to the attending surgeon that surgery was booked for the opposite limb, but he ignores the residents confers by saying the surgical mark is under the drape. What would be the most appropriate course of action for the resident at this time? Review Topic

Explanation

The most appropriate course of action for the resident at this time would be to perform a surgical timeout prior to the operation.
Wrong-site surgery is completely preventable by having the surgeon, in consultation with the patient when possible, place his or her initials on the operative site using a permanent marking pen and then operating through or adjacent to his or her initials. The intended site should be marked such that the mark will be visible after the patient has been prepped and draped. A "time-out" procedure should be done before the initiating of any surgical procedure to confirm the type of procedure, site, and side with all operating room personnel including residents.
Haynes et al. reviewed the effect of surgical safety checklists before surgery on the morbidity and mortality in a global population. They found the rate of death was 1.5% before the checklist was introduced and declined to 0.8% afterward (P=0.003). Inpatient complications occurred in 11.0% of patients at baseline and in 7.0% after introduction of the checklist (P<0.001).
Incorrect Answers:

Question 78

Pharmacoprophylaxis should be avoided in favor of a pneumatic compression device for a patient with

Explanation

DISCUSSION
For patients with known bleeding disorders, a pneumatic compression device alone is recommended over pharmacoprophylaxis to minimize risk for excessive bleeding and wound complications. Factor VIII deficiency (hemophilia) and active liver disease are the 2 conditions for which support is strongest to withhold anticoagulation. Protein C deficiency and protein S deficiency are associated with increased risk for thrombosis, as is the factor V Leiden mutation.
RESPONSES FOR QUESTIONS 159 THROUGH 162
Lateral femoral cutaneous
Superior gluteal
Inferior gluteal
Obturator
Sciatic
Which nerve listed above is at increased risk for injury when performing hip surgery through the following approaches?

Question 79

A 13-year-old girl with adolescent idiopathic scoliosis is otherwise healthy with a normal neurologic examination and she began her menstrual cycle 3 months ago. Standing radiographs show a high left thoracic curve from T1-T6 that measures 29 degrees, a right thoracic curve from T7-L1 that measures 65 degrees, and a left lumbar curve from L1-L5 that measures 31 degrees, correcting to 12, 37, and 10 degrees, respectively, on bending films. Her Risser sign is 1. What is the most appropriate management?

Explanation

DISCUSSION: The patient has typical adolescent idiopathic scoliosis with a right thoracic curve. This represents a Lenke-IB curve pattern; therefore, only treatment of the thoracic curve is required. The proximal thoracic and thoracolumbar curves are very flexible. The patient is Risser 1 and has just started her menstrual cycles; therefore, she is at significant risk for further curve progression. Bracing is not appropriate for a curve of this magnitude and will not halt the progression of this curve, nor will vertebral body stapling stop this curve. Vertebral body stapling is sometimes useful in small thoracic curves of less than 35 degrees and skeletally immature patients. Anterior and
14 • American Academy of Orthopaedic Surgeons
posterior spinal fusion is not required because the patient has no other risk factors, such as neurofibromatosis nor is she at risk for crankshaft. Anterior fusion is an option, but it is not listed.
REFERENCES: Lenke LG, Betz RR, Harmes J, et al: Adolescent idiopathic scoliosis: Anew classification to determine extent of spinal arthrodesis. J Bone Joint Surg Am 2001;83:1169-1181.
Lenke LG, Betz RR, Haher TR, et al: Multisurgeon assessment of surgical decision making in adolescent idiopathic scoliosis: Curve classification, operative approach, and fusion levels. Spine 2001;26:2347- 2353.

Question 80

What is the most common problem seen following epiphysiodesis for limb-length discrepancy?

Explanation

DISCUSSION: Errors in timing are by far the most common in this technically safe procedure. Incomplete growth arrest has been reported in up to 15% of patients versus timing errors in 61%. Fracture through the site has been reported rarely. Neurovascular and cartilaginous injury are extremely uncommon but always need to be considered when performing surgery in the vicinity of these structures.
REFERENCES: Blair VP III, Walker SJ, Sheridan JJ, Schoenecker PL: Epiphysiodesis: A problem of timing. J Pediatr Orthop 1982;2:281-284.
Raney ER: Limb-length discrepancy, in Fitzgerald RH, Kaufer H, Malkani AL (eds): Orthopaedics. St Louis, MO, Mosby, 2002, pp 1519-1526.

Question 81

A 33-year-old female with generalized ligamentous laxity is diagnosed with spontaneous atraumatic subluxation of the sternoclavicular joint. She notes mild, intermittent pain and a small amount of prominence to that area. What is the most appropriate treatment at this time?

Explanation

DISCUSSION: Spontaneous atraumatic subluxaton of the sternoclavicular joint is a rare condition and is generally associated with ligamentous laxity. Higginbotham et al reported that spontaneous atraumatic anterior subluxation of the sternoclavicular joint may occur during overhead elevation of the arm. The majority of cases are not painful, and the subluxation usually reduces with lowering the arm. Surgery is rarely indicated. Nonsurgical management, including patient education of the benign nature of the condition, is recommended. Rockwood et al reviewed a series of 37 patients with this condition and noted that at an average follow-up of eight years, the twenty-nine patients who were treated non-operatively had excellent results, with no limitations of activity or changes in lifestyle. The eight patients who were treated operatively (group II) had numerous problems, including noticeable scars, persistent instability, pain, or limitation of activity that resulted in an alteration in lifestyle. The referenced article by Higginbotham is a review of atraumatic disorders of the sternoclavicular joint.

Question 82

A 68-year-old man had a 3-year history of shoulder pain that failed to respond to nonsurgical management. Examination reveals forward elevation to 120 degrees and external rotation to 30 degrees. True AP and axillary radiographs and an axial CT scan are shown in Figures 1a through 1c. What management option would lead to the best long-term results? Review Topic

Explanation

The radiographs and CT scan reveal osteoarthritis with posterior subluxation and posterior bone loss. Total shoulder arthroplasty with reaming of the high side to neutralize the glenoid surface has been shown to yield better results than hemiarthroplasty. The amount of bone loss in this patient does not require posterior glenoid augmentation. Reverse total shoulder arthroplasty is indicated for rotator cuff tear arthropathy; therefore, it is not applicable. Arthroscopic debridement has yielded poor results with advanced osteoarthritis and posterior subluxation. Results from glenoid osteotomy have been variable and glenoid osteotomy is not indicated with associated osteoarthritis.

Question 83

A 28-year-old man has had a 2-week history of right posterior leg pain, with numbness and tingling in the same distribution. He denies any problems with bowel or bladder function. Examination shows intact motor strength in his bilateral lower extremities, with numbness to light touch in the lateral border of his right foot. Over the past 2 weeks, his leg pain has improved significantly. MRI scans are shown in Figures 57a and 57b. What is the most appropriate course of management? Review Topic

Explanation

MRI of lumbar spine
Repeat ESR/CRP and whole body bone scan
CT of lumbar spine
Dynamic flexion/extension plain film radiographs
Dynamic lateral bending plain film radiographs
This patient has clinical and radiographic features of failed spinal arthrodesis. CT scan have been shown to be the most relable method for assessing spinal fusion postoperatively.
Reported rates of nonunion following posterior spinal fusion range from 0-70%. Rates are variable due to the various operative techniques, underlying diagnoses as well as asymptomatic patients. Non-union may lead to changes in alignment, spinal instability and potential neurological injury. Static radiographs have long been used as a practical method of fusion assessment, but these tend to significantly overestimate the presence of a solid fusion. Lack of movement at a fused segment, on dynamic views, does not confirm fusion. CT offers excellent bony resolution and are less affected by metal artifact compared to MRI.
Patel et al. showed that tobacco use, malnutrition, oral anti-inflammatory use, multilevel fusion, prior spine surgery, and sagittal imbalance are all risk factors for spinal nonunion.
Mok et al. looked at erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels after spinal surgery and compared their usefulness as predictors of infectious complications in the early postoperative period. They found that CRP is more applicable, predictable, and responsive in the early postoperative period compared with ESR. Using a second rise or failure to decrease as expected for CRP is sensitive for infection.
Shelby et al. reviewed the radiological assessment of spinal fusion. They comment that fine-cut imaging, multiplanar reconstruction, and metal artifact reduction have increased the ability to assess fusion on CT.
Figure A shows a series of lateral radiographs of the lumbar spine with posterior spinal instrumentation. Illustration A shows a lateral CT scan image of multi-level pseudoarthrosis after posterior spinal instrumented fusion. Illustration B shows an
intra-operative
view
of
spinal
pseudoarthrosis
(white
arrow).
Incorrect
(SBQ12SP.19) A 41-year-old male presents with acute onset of low back pain that started when he was trying to lift a heavy box while helping his brother move apartments two days ago. The pain has been severe enough to cause him to miss work yesterday. He has no neurologic deficits. What are the chances he will return to work within 6 weeks? Review Topic
1 80 to 90%
2 70 to 80%
3 60 to 70%
4 50 to 60%
5 40 to 50%
Most adults (up to 80%) will experience an episode of low back pain in their lifetime. In those whose pain is severe enough to cause them to miss work, 60 to 70% will return by 6 weeks, and 80 to 90% will return by 12 weeks.
Low back pain is common in adults. Most patients experience resolution of symptoms quickly and have no lasting loss of function. However, 5 to 10% develop chronic pain. Recurrence of pain is common, and is part of the natural history, occurring in 20 to 72% of patients. After 12 weeks, return to work rates are slow.
Shen et al. review the nonoperative management of acute and chronic low back pain. The authors note that none of the available interventions has been proven by high quality large randomized controlled trials. The authors believe that low dose oral
steroids are safe in the short term and that injection therapy should not be used without a reasonable presumptive diagnosis.
Madigan et al. review the management of lumbar degenerative disease. The authors emphasize that the majority of patients improve within 6 weeks with or without treatment. For patients that do not, the authors do not recommend epidural injection, as there are no good studies to support their use in the treatment of discogenic back pain. When surgical treatment is indicated they state that arthrodesis is the gold standard, although the long term results of total disk arthroplasty are being elucidated.
Illustration A shows a table of available non-operative treatment modalities for back pain. Illustration B shows a list of possible diagnoses associated with acute low back pain, with those associated with neurogenic pain italicized. Illustration C shows a list of 'red flag' symptoms indicating serious/emergent causes of low back pain.
Incorrect
2:
Longer
to than
90%

Question 84

Which of the following factors is associated with improved outcomes following surgery for hip fractures?

Explanation

Many studies have looked at patient outcomes following hip fracture surgery. While early surgery in these patients is recommended, medical optimization prior to surgical intervention is warranted in all cases. Anesthetic type and discharge status have not been proven to alter patient outcomes. Total hip arthroplasty has improved function at 1 year compared with hemiarthroplasty; no changes in mortality have been reported.

Question 85

Prescribing touch (10 to 15 kg) weight-bearing would be most appropriate in the following scenario?

Explanation

Touch weight bearing (10 to 15 kg) regimens have shown to minimize joint reaction forces across the hip. This weight bearing restriction should be considered in patients who have undergone open reduction internal fixation of transtectal transverse posterior wall fractures.
The definition of touch weight bearing (also known as touch-down weight bearing) is ill-defined in the literature. Published data suggest touch weight bearing to be 10 to 15 kg of load applied to ground by the affected limb or less than 20% of body weight. In contrast, partial weight bearing is reported as 20 to 25 kg or 30% to 50% of body weight. Joint reaction forces across the hip have been shown to be lowest with touch weight-bearing. In this scenario, the foot should be flat against the ground so the flexor and extensor musculature that cross the hip are relaxed. With non-weight bearing restrictions, the musculature across the hip will be contracted, which increases contact pressures and joint reaction forces.
Rubin et al. looked at the validity of touch weight-bearing and partial weight bearing regimens. They found that most patients overload the limb up to 50% more than the target weight prescribed.
Lewis et al. showed that maintaining non-weight-bearing position of the involved leg produces increased compressive forces across the hip joint due to activation of the hip flexors compared to restricted weight-bearing.
Incorrect Answers:

Question 86

A 19-year-old collegiate offensive lineman injures his left elbow in a scrimmage. He reports reaching out with his left arm to prevent the defensive player from getting around him, and, as he grabbed the player, his elbow was forced into extension. He had immediate pain and weakness and heard a “pop.” He has mild swelling in the antecubital fossa and a prominent-appearing biceps muscle belly. His hook test result is abnormal at the elbow. Which type of contraction of the involved muscle most likely resulted in this lineman's injury?

Explanation

This patient had an eccentric muscle contraction (muscle lengthening while contracting) of his biceps muscle while trying to stop a defender from getting around him. This in turn caused failure of the distal biceps tendon, as evidenced by pain in the antecubital fossa, lack of elbow supination strength, and his positive biceps active test finding (supination/pronation of the forearm showing no motion of the biceps muscle belly). Eccentric contractors have the highest potential for building strength but also are at highest risk for injury. Concentric (muscle shortening with contraction), isometric (no change in muscle length with contracture), and isokinetic (constant velocity of muscle contraction with a variable force) do not describe the mechanism detailed. The loss of distal biceps attachment will result in loss of elbow supination strength in flexion (the biceps is the only supinator to cross the elbow) while still retaining elbow flexion (albeit weakened) because of the other elbow flexors (brachioradialis and brachialis). Consequently, treatment should be anatomic repair of the distal biceps insertion, which can be performed with a 2-incision or 1-incision technique. Although all of the listed complications have been reported with these techniques, LABC neuropraxia is by far the most common. Radiographs show that this athlete’s injury was repaired using a 1-incision technique with a cortical fixation device and a radial bone tunnel. This technique has gained favor because of its decreased incidence of heterotopic ossification and radioulnar synostosis compared with the 2-incision technique. The most troubling complication for most surgeons is the development of a posterior interosseous nerve (PIN) palsy, which this patient clearly demonstrates in addition to the more common LABCN upon postsurgical examination. Because the LABCN injury is typically a neuropraxia from retraction, a period of observation is indicated. PIN injury can result from excessive traction during surgical exposure or from entrapment by the fixation button. Considering the anatomy of the PIN, successful recovery of the nerve typically progresses based on the distance from the origin of the nerve to the muscle indicated. The extensor indicis proprius (EIP) muscle is the most distal muscle innervated and can be expected to recover last. First to return would be the EDC
followed by the ECU, EDQ, and, finally, the EIP.

Question 87

Resuscitation of a trauma patient who has been in hypovolemic shock is complete when which of the following has occurred?

Explanation

DISCUSSION: Shock can be defined as inadequate tissue perfusion. Resuscitation or the resolution of shock is defined as when oxygen debt has been repaid, tissue acidosis is eliminated, and aerobic metabolism has been restored in all tissue beds. The end points for resuscitation are not clearly defined, but occult shock can still be present in the setting of normal vital signs and normal urine output due to selective perfusion of organ systems.
REFERENCES: Tisherman SA, Barie P, Bokhari F, et al: Clinical practice guideline: End point of resuscitation. J Trauma 2004;57:898-912.
Moore FA, McKinley BA, Moore EE, et al: Inflammation and the Host Response to Injury, a large-scale collaborative project: Patient-oriented research core--standard operating procedures for clinical care. III. Guidelines for shock resuscitation. J Trauma 2006;61:82-89.
Englehart MS, Schreiber MA: Measurement of acid-base resuscitation end points: Lactate, base deficit, bicarbonate or what? Curr Opin Crit Care 2006;12:569-574.

Question 88

What antithrombotic agent is a selective factor I0a inhibitor? Review Topic

Explanation

Rivaroxaban is a selective factor I0a inhibitor. Aspirin is a cyclooxygenase inhibitor. Low-molecular-weight heparin is a nonspecific anticoagulant. Warfarin is a vitamin K antagonist and reduces production of clotting factors II, VII, IX, and X.

Question 89

A 47-year-old landscaper presents with worsening left shoulder pain and weakness. Three years ago, he injured the left shoulder in a fall and elected for nonoperative management to minimize time off from work. Physical therapy was effective until 6 months ago when his shoulder function worsened to the point that he is now unable to work. Examination of his active range of motion reveals forward elevation 120° with pain, abduction 100°, IR at neutral to T8 and ER at neutral 5°. He has a positive ER lag sign and Hornblower's sign. Belly press and lift-off tests are normal. A recent radiograph is shown in Figures A. MRI images are shown in Figures B and C. Which of the following is the best treatment option? Review Topic

Explanation

This patient has a chronic massive posterosuperior rotator cuff tear with marked atrophy, tendon retraction and loss of external rotation strength that is impacting his daily life. The best treatment option for this middle-aged laborer with an irreparable posterosuperior rotator cuff tear is a latissimus dorsi transfer to restore external rotation strength and motion.
Irreparable rotator cuff tears are marked by: (1) Superior displacement of the humeral head (AHI < 5-7mm), (2) Fatty infiltration of the rotator cuff muscles (Goutallier stage 3-4), (3) Increased duration of the tendon tear and (4) Profound external rotation weakness. These findings are predictive of poor-quality tissue and stiffness of the muscle-tendon unit, not amenable to primary repair. In this setting, a latissimus dorsi
transfer can be utilized to restore shoulder strength, function and improve pain. Relative contraindications include subscapularis deficiency, deltoid deficiency, pseudoparalysis of the shoulder and advanced glenohumeral arthritis.
Gerber et al. performed a case series analysis of 67 patients with irreparable rotator cuff tears managed with latissimus dorsi transfer. Patients with an intact subscapularis demonstrated improvement in pain, range of motion and strength postoperatively, while no improvement was noted in patients with subscapularis deficiency. The authors conclude that latissimus dorsi transfer should not be performed in the setting of poor subscapularis function.
Iannotti et al. found that better clinical results following latissimus dorsi transfer were associated with: preserved active shoulder range of motion and strength (specifically forward elevation > 90° and external rotation > 20°), synchronous firing of the transferred latissimus dorsi muscle and male gender.
Figure A is an AP radiograph of the left shoulder with superior migration of the humeral head (AHI < 5mm) and no evidence of glenohumeral arthritis. Figures B and C show a retracted posterosuperior rotator cuff tear and Goutallier stage 4 atrophy (more fat than muscle) of the supraspinatus, infraspinatus and teres minor, rendering this tear irreparable. Illustration A shows a latissimus dorsi transfer. The latissimus dorsi tendon is positioned over the top of the humeral head, covering most of the rotator cuff defect. The tendon is then secured to the subscapularis tendon edge and lesser tuberosity anteriorly, the remnant supraspinatus and infraspinatus tendons medially, and the greater tuberosity laterally.
Incorrect Answers:

Question 90

When compared with a conventional ultra-high molecular weight polyethylene (UHMWPE) -bearing surface in total hip arthroplasty, a highly cross-linked polyethylene (XLPE) -bearing surface is associated with

Explanation

A 30-year-old patient is indicated for distal femoral osteotomy. This procedure results in survivorship with
A. a functional result for at least 20 years.
B. a functional result that deteriorates within the first 10 years.
C. an eventual conversion to a constrained knee arthroplasty.
D. an eventual need for arthrodesis.
Distal femoral varus osteotomy (DFVO) is intended for patients younger than age 50, more active patients with isolated lateral compartment arthritis and valgus malalignment. Although the knee functional score improves at 1-year follow-up, the function scores significantly deteriorate at 10-year follow-up. At 15-year follow-up, the knee function further declines, resulting in an overall failure rate of 48.5%. DFVO provides longer lasting benefit in patients with better presurgical knee function.
Total knee arthroplasty following DFVO provides improved function and successful outcomes. Standard posterior stabilized components provide satisfactory stability after appropriate ligament balancing without the need for stemmed or highly constrained implants for most patients.

Question 91

Survival rates for children with soft-tissue sarcoma other than rhabdomyosarcoma are best correlated with

Explanation

DISCUSSION: In review of 154 patients with nonrhabdomyosarcoma, Rao reported that histologic grade, tumor invasiveness, and adequate surgical margin were the most important prognostic factors. Histologic subtype, use of adjuvant chemotherapy, and patient age were not as important. Size related to degree of invasiveness was not statistically significant.
REFERENCES: Rao BN: Nonrhabdomyosarcoma in children: Prognostic factors influencing survival. Semin Surg Oncol 1993;9:524-531.
Andrassy R, et al: Non-rhabdomyosarcoma Soft-Tissue Sarcomas: Pediatric Surgical Oncology. Philadelphia, PA, WB Saunders, p 221.

Question 92

A 69-year-old female sustains the injuries seen in Figures A and

Explanation

The radiographs and CT scan images show a depressed lateral tibial plateau fracture, which is correctly classified as a Schatzker III tibial plateau fracture. This fracture typically occurs as the result of the femoral condyle directly impacting the articular surface in older patients with osteopenia.
The referenced article by Bennett et al reviews the associated soft tissue injury with tibial plateau fractures. They found a 56% frequency of associated soft tissue injuries overall, with MCL injured in 20%, the LCL in 3% , the menisci in 20%, the peroneal nerve in 3%, and the anterior cruciate ligaments in 10%.
Schatzker type IV and type II fracture patterns were associated with the highest frequency of soft tissue injuries.

Question 93

271 Which of the following factors has been shown to contribute to poor results after anatomic reduction of posterior wall acetabulum fractures?

Explanation

Only 30% of posterior-wall acetabular fractures involve a single large fragment. The majority are multifragmentary or have areas of impaction. Unsatisfactory clinical results occur in more than 80% of patients treated nonsurgically. Operative management usually offers the best chance of preserving long-term joint function, but only if an anatomically reconstructed acetabulum can be achieved without complication. The keys to surgical success include maintaining the viability of the fracture fragments and the femoral head itself, using bone grafts and buttress plating to support elevated and comminuted fragments, and protecting the neurovascular structures at risk.
Complications can include sciatic nerve injury (incidence, 3% to 18%), heterotopic ossification (7% to 20%), and osteonecrosis of the femoral head (5% to 8%). Despite the relative simplicity of this acetabular fracture, unsatisfactory outcomes after surgical repair of the posterior wall occur in at least 18% to 32% of cases, results that are worse than for most of the other more complex acetabular fracture patterns.
Moed BR, et al. Results of operative treatment of fractures of the posterior wall of the acetabulum. JBJS AM 2002:84:752-758
Matta JM: Fractures of the acetabulum: Accuracy of reduction and clinical results in patients managed operatively within three weeks after the injury. JBJS Am 1996;78:1632-1645
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Question 94

Compared to similar patients who do not donate autologous blood, patients with normal baseline hemoglobin who donate autologous blood prior to undergoing primary total hip arthroplasty are likely to

Explanation

DISCUSSION: Billote and associates compared patients with normal baseline hemoglobin levels who did and did not donate autologous blood prior to total hip arthroplasty. No patients received allogeneic blood perioperatively, and the autologous donors had significantly lower hemoglobin levels at the time of surgery and in the recovery room. Of the autologous donors, 69% received an autologous transfusion. The authors concluded that autologous donation was unnecessary in patients undergoing primary total hip arthroplasty who had a normal hemoglobin.
REFERENCES: Billote D, Glisson SN, Green D, Wixson RL: A prospective, randomized study of preoperative autologous donation for hip replacement surgery. J Bone Joint Surg Am 2002;84:1299-1304.
Koval KJ (ed): Orthopaedic Knowledge Update 7. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 47-53.

Question 95

What adaptations occur in the dominant shoulder of throwers compared to their nondominant shoulder? Review Topic

Explanation

Pitchers change rotation during adolescent growth with external rotation of the proximal humerus. The result is increased external rotation and decreased internal rotation, resulting in a normal total arc of motion. External rotation lengthens the arc of acceleration, resulting in increased velocity. The shorter arc of internal rotation, associated with a tight posterior capsule, makes deceleration of the arm more difficult, which may lead to overuse injuries.

Question 96

When compared with the normal anterior cruciate ligament (ACL), placement of an anterior cruciate ligament graft in the over-the-top position on the femoral side has what effect on its function?

Explanation

DISCUSSION: The placement of ACL graft with respect to its femoral and tibial attachments has a significant effect on its function. Evidence has shown that if the graft is placed in the over-the-top position, the graft will become lax in flexion and more taut with extension. Conversely, if the graft is placed too anterior on the femoral side, it will tighten in flexion and become lax in extension.
REFERENCES: Azar FM: Revision anterior cruciate ligament reconstruction. Instr Course Lect 2002;51:335-342.
Draganich LF, Hsieh YF, Sherwin SH, et al: Intra-articular anterior cruciate ligament graft placement on the average most isometric line on the femur: Does it reproducibly restore knee kinematics? Am J Sports Med 1999;27:329-334.
Bylski-Austrow DI, Grood ES, Hetzy MS, et al: Anterior cruciate ligament replacements: A mechanical study of femoral attachment location, flexion angle at tensioning, and initial tensioning. J Orthop Res 1990;8:522-531.

Question 97

A 46-year-old male is involved in a motor vehicle accident and suffers a proximal humerus fracture. Operative treatment is recommended, and plate fixation is performed through an extended anterolateral acromial approach. Which of the following structures is at increased risk of injury using this surgical exposure compared to the deltopectoral approach?

Explanation

DISCUSSION: The anterolateral acromial approach was developed to allow less invasive treatment of proximal humerus fractures. The plane of the avascular anterior deltoid raphe is utilized, and the axillary nerve is at particular risk of injury and must be identified and protected. With this approach, anterior dissection near the critical blood supply is avoided, substantial muscle retraction is minimized, and the lateral plating zone is directly accessed.
Gardner et al evaluated 23 patients who had acute displaced fractures of the proximal humerus treated with the anterolateral acromial approach and either a locking plate or an intramedullary nail. At one year post-op, there were no axillary nerve deficits, and they found that the approach allowed direct access to the lateral fracture planes for fracture reduction and plate placement or safe nail and interlocking screw placement.
Gardner et al, in another study, performed cadveric dissection using the extended anterolateral acromial approach and measured multiple parameters regarding the axillary nerve. The nerve was predictably found approximately 35 mm from the prominence of the greater tuberosity.
Morgan et al performed a cadaveric study to describe the anatomic insertion point of the deltoid onto the proximal humerus. They found that the deltoid insertion is long and broad, and that placement of 4.5-mm plate would result in detaching 13.5 mm of its insertional footprint. This would leave half of the insertion still attached to the humerus.
Illustration A identifies the location of the incision for the anterolateral acromial exposure , and Illustration B shows the position of the axillary nerve in relation to the approach.

Question 98

The use of multiagent adjuvant chemotherapy is associated with a clear survival benefit in which of the following diseases?

Explanation

DISCUSSION: The use of multiagent chemotherapy has been shown to be associated with a survival benefit in patients with osteosarcoma. The use of chemotherapy in adults with soft-tissue sarcoma remains somewhat controversial. It has not been associated with improved survival rates in patients with renal carcinoma, dedifferentiated chondrosarcoma, or melanoma.
REFERENCES: Menendez LR (ed): Orthopaedic Knowledge Update: Musculoskeletal Tumors. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, p 53.
Link M, Goorin A, Miser A, et al: The effect of adjuvant chemotherapy and relapse free survival in patients with osteosarcoma of the extremity. N Engl J Med 1986;314:1600-1606.

Question 99

A 3-year-old child has refused to walk for the past 2 days. Examination in the emergency department reveals a temperature of 102.2 degrees F (39 degrees C) and limited range of motion of the left hip. An AP pelvic radiograph is normal. Laboratory studies show a WBC count of 9,000/mm P 3 P , an erythrocyte sedimentation rate (ESR) of 65 mm/h, and a C-reactive protein level of 10.5 mg/L (normal < 0.4). What is the next most appropriate step in management?

Explanation

DISCUSSION: Examination reveals an irritable hip, creating a differential diagnosis of transient synovitis versus pyogenic hip arthritis. Kocher and associates described four criteria to help predict the presence of infection: inability to bear weight, fever, ESR of more than 40 mm/h, and a peripheral WBC count of more than 12,000/mmP³^P. This patient meets three of the four criteria, with a positive predictive value of 73% to 93% for joint infection. Therefore, aspiration of the hip is warranted, with a high likelihood that emergent hip arthrotomy will be indicated. Ideally, intravenous antibiotics should be administered after culture material has been obtained from needle aspiration of the hip. An urgent bone scan is better indicated as a screening test for sacroiliitis or diskitis. If the arthrocentesis proves negative, CT or MRI of the pelvis may be indicated to rule out a pelvic or psoas abscess.
REFERENCES: Del Beccaro MA, Champoux AN, Bockers T, et al: Septic arthritis versus transient synovitis of the hip: The value of screening laboratory tests. Ann Emerg Med 1992;21:1418-1422.
Kocher MS, Mandiga R, Zurakowski D, et al: Validation of a clinical prediction rule for the differentiation between septic arthritis and transient synovitis of the hip in children. J Bone Joint Surg Am 2004;86:1629-1635.
Kocher MS, Zurakowski D, Kasser JR: Differentiating between septic arthritis and transient synovitis of the hip in children: An evidence-based clinical prediction algorithm. J Bone Joint Surg Am 1999;81:1662-1670.

Question 100

A 14-year-old girl has idiopathic scoliosis with a 52-degree right thoracic curve and a 36-degree left lumbar curve. The rotation of the apical vertebra appears greater in the thoracic curve. A sagittal view radiograph shows the spine to be virtually straight. The iliac apophyses are Risser 2. Treatment should consist of

Explanation

The patient’s curve is beyond the limit for bracing to be effective (40 degrees). Therefore, surgical treatment should be utilized. King type II curves (predominant thoracic curve with secondary lumbar curve) historically has used selective posterior thoracic fusion with segmental hook systems and rotation maneuvers to correct the thoracic curve and compensatory lumbar curve. The patient’s primary curve is thoracic and lumbar fusion would be contraindicated.

Full Question & Answer Text (for Search Engines)

Question 1:

Options:

Proximal tibial/fibular osteotomy with acute correction and pin fixation
Proximal tibial/fibular osteotomy with gradual correction and external fixation
MRI of the proximal tibial physis
Medial proximal tibial hemiepiphysiodesis
Continued observation

Correct Answer: Continued observation

Explanation:

DISCUSSION: The tibia has grown into valgus secondary to the proximal fracture. This occurs in about one half of these injuries, and maximal deformity occurs at 18 months postinjury. The deformity gradually improves over several years, with minimal residual deformity. Therefore, treatment at this age is unnecessary as there is a high rate of recurrence and complications regardless of technique. The valgus deformity is not a result of physeal injury or growth arrest. Medial proximal tibial hemiepiphysiodesis is an excellent method of correcting the residual deformity but is best reserved until close to the end of growth.
REFERENCES: Brougham DI, Nicol RO: Valgus deformity after proximal tibial fractures in children. J Bone Joint Surg Br 1987;69:482.
McCarthy JJ, Kim DH, Eilert RE: Posttraumatic genu valgum: Operative versus nonoperative treatment. J Pediatr Orthop 1998;18:518-521.
Robert M, Khouri N, Carlioz H, et al: Fractures of the proximal tibial metaphysis in children: Review of a series of 25 cases. J Pediatr Orthop 1987;7:444-449.

Question 2:

-The main blood supply to the capital femoral epiphysis in a 10-year-old child is supplied from the

Options:

artery of the ligamentum teres.
epiphyseal branch of the lateral femoral circumflex artery.
posterosuperior and posteroinferior retinacular branches of the lateral femoral circumflex artery.
posterosuperior and posteroinferior retinacular branches of the medial femoral circumflex artery. DISCUSSION-Before the age of 4 years, blood to the femoral head is supplied by the medial and lateral femoral circumflex arteries as well as the artery of the ligamentum teres. After the age of 4, the blood supply through the artery of the ligamentum teres diminishes. The lateral femoral circumflex system regresses,and its flow into the physis and epiphysis diminishes significantly so the medial femoral circumflex artery becomes the predominant blood supply to the metaphysis. The medial femoral circumflex artery provides the principal blood supply to the proximal femur via its posterosuperior and posteroinferior retinacular branches.

Correct Answer: posterosuperior and posteroinferior retinacular branches of the medial femoral circumflex artery. DISCUSSION-Before the age of 4 years, blood to the femoral head is supplied by the medial and lateral femoral circumflex arteries as well as the artery of the ligamentum teres. After the age of 4, the blood supply through the artery of the ligamentum teres diminishes. The lateral femoral circumflex system regresses,and its flow into the physis and epiphysis diminishes significantly so the medial femoral circumflex artery becomes the predominant blood supply to the metaphysis. The medial femoral circumflex artery provides the principal blood supply to the proximal femur via its posterosuperior and posteroinferior retinacular branches.

Question 3:

Options:

Left upper thoracic curve 16 degrees and right main thoracic curve 18 degress, Risser stage in figure B
Right thoracolumbar curve 35 degrees, Risser stage in figure C
Left upper thoracic curve 15 degrees and right main thoracic curve 30 degrees, Risser stage in figure B
Left upper thoracic curve 26 degrees and right main thoracic curve 51 degrees, Risser stage in figure A
Left thoracolumbar curve 19 degrees, Risser stage in figure A

Correct Answer: Left upper thoracic curve 16 degrees and right main thoracic curve 18 degress, Risser stage in figure B

Explanation:

Question 4:

The talocrural angle of an ankle mortise x-ray is formed between a line perpendicular to the tibial plafond and a line drawn:

Options:

perpendicular to the medial clear space
parallel to the talar body
between the tips of the malleoli
perpendicular to the shaft of the fibular
parallel to the subtalar joint

Correct Answer: perpendicular to the medial clear space

Explanation:

Question 5:

Figure 10 shows the AP radiograph of an ambulatory 76-year-old patient. What is the most appropriate surgical treatment option for this patient?

Options:

Revision arthroplasty using a cemented femoral component
Impaction allografting of the femoral component
Proximal femoral replacement arthroplasty
Resection arthroplasty
Hip arthrodesis

Correct Answer: Proximal femoral replacement arthroplasty

Explanation:

DISCUSSION: The patient has a periprosthetic fracture around a loose cemented femoral component. The proximal bone stock is poor; therefore, this fracture may be categorized as Vancouver 3-B. Hip arthrodesis and resection arthroplasty provide suboptimal results, particularly for ambulatory patients. Although impaction allografting may be an option to restore the bone stock in a younger patient, the latter procedure will be very difficult to perform when the proximal bone is poor in quality and fractured. Cementing another component into this wide femur is not an option. The best option for revision of the femoral component in this elderly patient is proximal femoral replacement arthroplasty.
REFERENCES: Malkani AL, Settecerri JJ, Sim FH, et al: Long-term results of proximal femoral replacement for non-neoplastic disorders. J Bone Joint Surg Br 1995;77:351-356.
Parvizi J, Sim FH: Proximal femoral replacements with megaprostheses. Clin Orthop 2004;420:169-175.

Question 6:

A diskectomy is performed in which the disk space is not aggressively debrided. When compared to techniques that involve aggressive debridement of the disk space, this results in

Options:

less intraoperative blood loss.
an increased rate of recurrent disk herniation.
a shorter length of hospital stay.
a higher rate of surgical complications.

Correct Answer: an increased rate of recurrent disk herniation.

Explanation:

DISCUSSION
This patient has disk herniation at the left L5-S1 level. This will generally affect the traversing S1 nerve. The S1 dermatome is on the lateral aspect and sole of the foot.
Surgical treatment generally involves a diskectomy with removal of the herniated fragment. This can be performed via a conventional open approach or minimally invasive endoscopic technique. Several recent meta-analyses have demonstrated equivalent outcomes with regard to leg pain and clinical outcomes. Although minimally invasive techniques have been associated with an increased rate of dural tear, the overall complication rate between the 2 techniques is not significantly different. Several studies have demonstrated a substantial learning curve associated with minimally invasive techniques, and the rate of complications decreases significantly with surgeon experience.
When performing a diskectomy, the herniated fragment alone can be removed (sequestrectomy) or some of the disk that remains in the disk space can be removed (complete diskectomy). Studies have shown no change in surgical time, blood loss, length of stay, or surgical complications when performing a sequestrectomy (compared to a more complete diskectomy). A sequestrectomy is associated with a higher rate of recurrent disk herniation at the surgical level.
RECOMMENDED READINGS
Kamper SJ, Ostelo RW, Rubinstein SM, Nellensteijn JM, Peul WC, Arts MP, van Tulder MW. Minimally invasive surgery for lumbar disc herniation: a systematic review and meta-analysis.
Eur Spine J. 2014 May;23(5):1021-43. doi: 10.1007/s00586-013-3161-2. Epub 2014 Jan 18.
PubMed PMID: 24442183.
View Abstract at PubMed
Dasenbrock HH, Juraschek SP, Schultz LR, Witham TF, Sciubba DM, Wolinsky JP, Gokaslan ZL, Bydon A. The efficacy of minimally invasive discectomy compared with open discectomy: a meta-analysis of prospective randomized controlled trials. J Neurosurg Spine. 2012 May;16(5):452-62. doi: 10.3171/2012.1.SPINE11404. Epub 2012 Mar 9. PubMed PMID:

Question 7:

Which of the following would be associated with the spinal deformity shown in Figures 79a and 79b? Review Topic

Options:

Improved gait
Deformity progression
Delayed satiety
No further risk of fracture
Improved lung function

Correct Answer: Deformity progression

Explanation:

Question 8:

Options:

Valgus extension overload
Varus posteromedial rotatory instability (VPMRI) C. Valgus posterolateral rotatory instability (VPLRI) D. Olecranon bursitis The patient has valgus extension overload. This is a spectrum of pathologies, often seen in pitchers, that begins with posteromedial impingement between the medial olecranon and posterior trochlea during forceful elbow extension. As a result, a medial olecranon osteophyte is typically the first notable imaging finding. As pathology increases, there can be progressive damage to the medial collateral ligament (MCL), degeneration of the radiocapitellar articulation, and neuritis of the ulnar nerve. VPMRI is often associated with a large anteromedial coronoid fracture and posterior band MCL rupture. VPLRI occurs when the lateral collateral ligament complex is ruptured. Olecranon bursitis presents with focal swelling or a fluid collection over the posterior aspect of the olecranon.

Correct Answer: Valgus extension overload

Explanation:

A patient sustains a displaced diaphyseal humerus fracture following a motor vehicle accident. Open reduction internal fixation is indicated due to concomitant lower extremity trauma and is planned through an anterior approach. Which intramuscular interval is exploited during the deep dissection of the mid-humerus in this approach?
A. Lateral head of triceps (radial nerve) and brachialis
(musculocutaneous nerve)
B. Lateral head of the triceps (radial nerve) and biceps brachii
(musculocutaneous nerve)
C. Lateral brachialis (radial nerve) and medial brachialis
(musculocutaneous nerve)
D. Brachialis (musculocutaneous nerve) and coracobrachialis
(musculocutaneous nerve)

Question 9:

A 60-year-old woman with a history of breast cancer has progressive paraparesis. The MRI scan is shown in Figure 28. What form of management is most likely to restore or maintain ambulation?

Options:

Radiation therapy and a thoracolumbosacral orthosis
Laminectomy alone
Laminectomy and radiation therapy
Laminectomy and posterior fusion
Anterior decompression and stabilization

Correct Answer: Anterior decompression and stabilization

Explanation:

Question 10:

What is the most common cause of errors that harm patients? Review Topic

Options:

Communication breakdown
Equipment breakdown
Nursing competence
Patient noncompliance
Physician competence

Correct Answer: Communication breakdown

Explanation:

Question 11:

Halo treatment for preadolescent children typically requires the use of which of the following? Review Topic

Options:

4 to 6 pins with an insertional torque of 1 to 5 in-lb
4 to 6 pins with an insertional torque of 4 to 6 in-lb
4 to 6 pins with an insertional torque of 6 to 8 in-lb
8 to 12 pins with an insertional torque of 1 to 5 in-lb
8 to 12 pins with an insertional torque of 4 to 6 in-lb

Correct Answer: 8 to 12 pins with an insertional torque of 1 to 5 in-lb

Explanation:

Question 12:

What is the most appropriate treatment for a chordoma involving the sacrum?

Options:

Chemotherapy
External beam radiation therapy
En bloc surgical resection with negative margins
Intralesional resection followed by radiation therapy
Intralesional resection followed by chemotherapy

Correct Answer: En bloc surgical resection with negative margins

Explanation:

Question 13:

Options:

High hip center
Anatomic hip center with trochanteric osteotomy and progressive femoral shortening
Anatomic hip center with subtrochanteric shortening osteotomy
Iliofemoral lengthening followed by an anatomic hip center

Correct Answer: Anatomic hip center with subtrochanteric shortening osteotomy

Explanation:

Question 14:

A 23-year-old woman falls from a bicycle and sustains a right knee injury. Figures 12a through 12d show radiographs and MRI scans of the knee. What is the most likely diagnosis?

Options:

Posterior cruciate ligament avulsion from the tibia
Anterior cruciate ligament avulsion from the tibia
Avulsion of the lateral meniscus anterior horn
Midsubstance posterior cruciate ligament rupture
Midsubstance anterior cruciate ligament rupture

Correct Answer: Anterior cruciate ligament avulsion from the tibia

Explanation:

DISCUSSION: The radiographs and MRI scans both show an avulsion of the anterior cruciate ligament, which has been described by Meyers and McKeever in three different fracture patterns. Type I fractures are nondisplaced or have minimal displacement of the anterior margin. Type II fractures have superior displacement of their anterior aspect with an intact posterior hinge. Type III fractures are completely displaced. Although the injury is visible on the radiographs, it is more subtle in adults than children. Thus, MRI is helpful in clarifying this injury in adults. Open or arthroscopic reduction and internal fixation is recommended for type II and type III fractures that do not respond to closed reduction.
REFERENCES: Meyers MH, McKeever FM: Fracture of the intercondylar eminence of the tibia. J Bone Joint Surg Am 1970;52:1677-1684.
Wiss DA, Watson JT: Fractures of the tibial plateau, in Rockwood CA, Green DP, Bucholz RW, et al (eds): Rockwood and Green’s Fractures in Adults. Philadelphia, PA, Lippincott-Raven, 1996, pp 1920-1953.
Lubowitz JH, Elson WS, Guttmann D: Arthroscopic treatment of tibial plateau fractures: Intercondylar eminence avulsion fractures. Arthroscopy 2005;21:86-92.

Question 15:

A 23-year-old soccer player sustains a grade III complete posterior cruciate ligament (PCL) tear after colliding with another player. In reconstructing the PCL, it is optimal to reconstruct the

Options:

anterolateral bundle and tension the graft at 10° of flexion.
anterolateral bundle and tension the graft at 90° of flexion.
posteromedial bundle and tension the graft at 10° of flexion.
posteromedial bundle and tension the graft at 45° of flexion.
posteromedial bundle and tension the graft at 90° of flexion.

Correct Answer: anterolateral bundle and tension the graft at 90° of flexion.

Explanation:

Question 16:

Options:

Substance P
Glutamate
Rho kinase
Nitric oxide

Correct Answer: Nitric oxide

Explanation:

EXPLANATION:
Nitric oxide is the only transmitter listed that is not inhibited by botulinum toxin. Substance P and glutamate are inhibited by botulinum toxin from release by pain nociceptors, thus reducing pain. Fonseca and associates have postulated that botulinum toxin inhibits the RhoA kinase pathway by blocking reactive oxygen species, which in turn does not allow actin/myosin to activate, thus preventing vasoconstriction of smooth muscle. Blocking the RhoA kinase pathway allows the action of nitric oxide to be unopposed, causing vasodilation. Nitric oxide is a potent vasodilator. Thus, botulinum toxin
promotes nitric oxide activity to increase vasodilation.

Question 17:

The nucleus pulposus of the intervertebral disk consists of chondrocyte-like cells that have a limited vascular supply and generate energy through which of the following?

Options:

Anaerobic glycolysis
Kreb's cycle
Ketosis
Gluconeogenesis
Lipogenesis

Correct Answer: Anaerobic glycolysis

Explanation:

Question 18:

Options:

Completion of the surgical procedure with continued monitoring
Reversal of the corrective maneuver and consideration of a wake-up test
Administration of high dose corticosteroids intraoperatively
Removal of all instrumentation
Discontinue monitoring

Correct Answer: Reversal of the corrective maneuver and consideration of a wake-up test

Explanation:

Question 19:

What strategy has proven most effective in preventing transmission of methicillin-resistant Staphylococcus aureus among teammates? Review Topic

Options:

Separate players with infections in a separate locker room or changing area.
Treat teammates of the infected player with prophylactic antibiotics.
Cover any skin lesions with occlusive dressing during sporting activity.
Ban players with infections from any team event.

Correct Answer: Cover any skin lesions with occlusive dressing during sporting activity.

Explanation:

Question 20:

During fracture healing, granulation tissue tolerates the greatest strain before failure so that mature bone can eventually bridge the fracture gap during healing. What is the definition of strain?

Options:

Amount of force an object can withstand until plastic deformation is lost
Change in length / original length of an object due to an external force
Relationship of stiffness to time-dependent loading
Force intensity / volume
Force intensity / cross sectional area

Correct Answer: Amount of force an object can withstand until plastic deformation is lost

Explanation:

Question 21:

The sublime tubercle of the elbow serves as the insertion site of the Review Topic

Options:

anterior bundle of the medial collateral ligament.
posterior bundle of the medial collateral ligament.
transverse bundle of the medial collateral ligament.
annular ligament.
lateral collateral ligament.

Correct Answer: anterior bundle of the medial collateral ligament.

Explanation:

The anterior bundle originates on the anteroinferior medial humeral epicondyle and inserts on the medial portion of the coronoid, known as the sublime tubercle.

Question 22:

.What is the most appropriate treatment if instability is present at the time of evaluation?

Options:

TEA
Distal humeral replacement arthroplasty
Arthroscopic release with debridement
Soft-tissue interposition arthroplasty DISCUSSION.. The radiographs reveal ulnohumeral arthrosis with relative sparing of the radiocapitellar articulation secondary to underlying osteoarthritis. Arthrosis of the elbow joint in this young and active patient presents a treatment dilemma for the surgeon. Interposition arthroplasty allows for improved function with pain relief and no weight-lifting restrictions, as required with TEA. This option is an intermediate procedure that preserves bone stock and allows for conversion to a TEA if necessary. Conventional TEA would provide pain relief with improved range of motion, but activity limitation and lifetime weight restrictions make this an undesirable option. Arthroscopic debridement is not an option, considering the previous failure from this modality. Contraindications for soft-tissue interposition arthroplasty include elbow instability, active infection, and pain without motion loss. Common complications associated with this procedure include instability, infection, ulnar neuropathy, bone resorption, and heterotopic bone formation.

Correct Answer: Soft-tissue interposition arthroplasty DISCUSSION.. The radiographs reveal ulnohumeral arthrosis with relative sparing of the radiocapitellar articulation secondary to underlying osteoarthritis. Arthrosis of the elbow joint in this young and active patient presents a treatment dilemma for the surgeon. Interposition arthroplasty allows for improved function with pain relief and no weight-lifting restrictions, as required with TEA. This option is an intermediate procedure that preserves bone stock and allows for conversion to a TEA if necessary. Conventional TEA would provide pain relief with improved range of motion, but activity limitation and lifetime weight restrictions make this an undesirable option. Arthroscopic debridement is not an option, considering the previous failure from this modality. Contraindications for soft-tissue interposition arthroplasty include elbow instability, active infection, and pain without motion loss. Common complications associated with this procedure include instability, infection, ulnar neuropathy, bone resorption, and heterotopic bone formation.

Question 23:

The vascularity of the digital flexor tendons is significantly richer in what cross-sectional region?

Options:

Volar ulnar quadrant
Volar radial quadrant
Peripheral one third
Dorsal one half
Center

Correct Answer: Dorsal one half

Explanation:

Question 24:

During cemented total hip arthroplasty, peak pulmonary embolization of marrow contents occurs when the

Options:

hip is dislocated.
femoral neck is osteotomized.
acetabulum is prepared.
acetabular component is inserted.
femoral stem is inserted.

Correct Answer: femoral stem is inserted.

Explanation:

DISCUSSION: Peak embolization is observed during femoral stem insertion. Embolization is also observed during acetabular preparation and hip reduction.
REFERENCES: Lewallen DG, Parvizi J, Ereth MH: Perioperative mortality associated with hip and knee arthroplasty, in Morrey BF (ed): Joint Replacement Arthroplasty, ed 3. Philadelphia, PA, Churchill-Livingstone, 2003, pp 119-127.
Ereth MH, Weber JG, Abel MD, et al: Cemented versus noncemented total hip arthroplasty: Embolism, hemodynamics, and intrapulmonary shunting. Mayo Clin Proc 1992;67:1066-1074.

Question 25:

Options:

Bed rest with skeletal traction (distal femur traction pin)
Calcium supplements
Crutches with protected weight bearing
Open reduction and internal fixation
Pulsed ultrasound treatment

Correct Answer: Crutches with protected weight bearing

Explanation:

Question 26:

What is the primary indication for performing an arthroscopic synovectomy on a patient with hemophilia that is the result of factor VIII deficiency?

Options:

Joint pain with radiographic evidence of joint space narrowing
Joint stiffness that has not improved with physiotherapy and bracing
Recurrent joint bleeding despite optimal medical management
Prophylaxis for joint preservation in severe hemophilia (factor VIII level <1%)
Decreasing ambulatory endurance despite optimal medical management

Correct Answer: Recurrent joint bleeding despite optimal medical management

Explanation:

DISCUSSION: Improved medical management has changed musculoskeletal outcomes for individuals with hemophilia. Patients with severe hemophilia receiving prophylactic administration of factor VIII may never develop a target joint that requires further orthopaedic intervention. Patients with moderate hemophilia and those patients with severe hemophilia not receiving prophylactic treatment will still develop joints that have recurrent hemarthroses. When recurrent hemarthrosis continues despite optimal medical management, synovectomy is indicated. While synovectomy is predictable in its ability to decrease joint bleeding, it does not necessarily improve joint range of motion or prevent the development of hemophilic arthropathy over time. It will not reverse articular damage to the joint once it has developed.
REFERENCES: Dunn AL, Busch MT, Wyly JB; et al: Arthroscopic synovectomy for hemophilic joint disease in a pediatric population. J Pediatr Orthop 2004;24:414-426.
Journeycake JM, Miller KL, Anderson AM, et al: Arthroscopic synovectomy in children and adolescents with hemophilia. J Pediatr Hematol Oncol 2003;25:726-731.

Question 27:

Options:

pectoralis transfer to the medial border of the scapula.
pectoralis transfer to the inferior border of the scapula.
lateral transfer of the levator scapulae only.
lateral transfer of the levator scapulae and rhomboid minor and major.
latissimus dorsi transfer.

Correct Answer: lateral transfer of the levator scapulae and rhomboid minor and major.

Explanation:

Question 28:

Options:

No additional consent needed
Verbal approval
Written approval
Written approval with notarization
Telephone consent witnessed by a nurse

Correct Answer: No additional consent needed

Explanation:

Question 29:

An 8-month-old infant has an infection of the fingertip as shown in Figure 22. If neglected, the anticipated path of ascending infection is the fingertip, the flexor sheath, and the

Options:

midpalmar space.
thenar space.
hypothenar space.
ulnar bursa.
radial bursa.

Correct Answer: midpalmar space.

Explanation:

Question 30:

Options:

Observation and NSAID use as needed
MRI scan
Bone biopsy
Serum protein electrophoresis (SPEP) and urine protein electrophoresis (UPEP).

Correct Answer: Observation and NSAID use as needed

Explanation:

DISCUSSION
The radiograph shown is consistent with Paget disease of the bone. It demonstrates classic findings of widened lamellae and disorganized sclerotic and lytic areas. The cause is not clearly defined, but may be linked to a viral infection and subsequent alterations of osteoblastic and osteoclastic activity. Most patients are asymptomatic, and Paget disease is often found incidentally on radiographs. In this case, the patient’s symptoms likely were caused by hip arthritis, but Paget disease can cause diffuse bone pain in some cases. Considering the patient’s mild and short-term symptoms, observation and NSAID use is most appropriate. An MRI scan or biopsy is indicated if sarcomatous transformation is suspected, but this condition is rare and is associated with a substantial, unrelenting increase in pain. SPEP and UPEP are tests for multiple myeloma, of which the radiographs show no signs.
RECOMMENDED READINGS
Ralston SH. Pathogenesis of Paget's disease of bone. Bone. 2008 Nov;43(5):819-25. doi: 10.1016/j.bone.2008.06.015. Epub 2008 Jul 11. Review. PubMed PMID: 18672105.
View Abstract at PubMed
Bonenberger E, Einhorn T. Metabolic bone diseases. In: Callaghan JJ, Rosenberg
AG, Rubash HE, eds. The Adult Hip. 2nd ed. Philadelphia, PA: Lippincott Williams
14
& Wilkins; 2007:514-533.

Question 31:

A 30-year-old farmer undergoes replantation of an above-the-elbow amputation. What form of management is most important following this surgery?

Options:

High volume diuresis with alkalinization of the urine
Systemic heparinization of the patient for 72 hours
Elevation of the extremity, with maintanence of the patient’s room temperature at 80 degrees F (26.6 degrees C)
Satellite ganglion continuous sympathetic block
Daily IV administration of low-molecular-weight dextran

Correct Answer: High volume diuresis with alkalinization of the urine

Explanation:

Question 32:

After making a tackle, a football player is found prone and unconscious without spontaneous respirations. Initial management should consist of

Options:

log roll to a supine position, helmet removal, and initiation of assisted breathing.
log roll to a supine position, head and neck stabilization, face mask removal, and CPR.
log roll onto a spine board, head and neck stabilization, face mask removal, and CPR.
head and neck stabilization, log roll to a supine position, helmet removal, and initiation of assisted breathing.
head and neck stabilization, log roll to a supine position, face mask removal, and initiation of assisted breathing.

Correct Answer: head and neck stabilization, log roll to a supine position, face mask removal, and initiation of assisted breathing.

Explanation:

Question 33:

Options:

Irrigation and debridement, external fixation of the ankle and foot, traction and pinning of the femur, open reduction and internal fixation of the forearm
Irrigation and debridement, external fixation of the ankle, foot, and femur, splinting of the forearm
Irrigation and debridement and open reduction and internal fixation of the ankle and foot, intramedullary nailing of the femur, open reduction and internal fixation of the forearm
Irrigation and debridement and open reduction and internal fixation of the ankle and foot, intramedullary nailing of the femur, splinting of the forearm
Irrigation and debridement, external fixation of the foot and ankle, intramedullary nailing of the femur, open reduction and internal fixation of the forearm

Correct Answer: Irrigation and debridement, external fixation of the ankle, foot, and femur, splinting of the forearm

Explanation:

DISCUSSION: The patient appears to be a borderline or unstable surgical patient following her initial trauma and spleenectomy (high base excess and low urine output). She needs continued resuscitation and minimal additional blood loss. This is best accomplished with irrigation and debridement of the ankle, external fixation of the ankle, foot, and femur, and splinting of the forearm. A traction pin for the femoral fracture will not control bleeding as well as an external fixator. Intramedullary nailing of the femur and open reduction and internal fixation of the forearm would be appropriate in patients that are euvolemic and stable.
REFERENCES: Pape HC, Hildebrand F, Pertschy S, et al: Changes in the management of femoral shaft fractures in polytrauma patients: From early total care to damage control orthopedic surgery. J Trauma 2002;53:452-461.
Taeger G, Ruchholtz S, Waydhas C, et al: Damage control orthopedics in patients with multiple injuries is effective, time saving, and safe. J Trauma 2005;59:409-416.
Harwood PJ, Giannoudis PV, van Griensven M, et al: Alterations in the systemic inflammatory response after early total care and damage control procedures for femoral shaft fracture in severely injured patients. J Trauma 2005;58:446-452.
Renaldo N, Egol K: Damage-control orthopaedics: Evolution and practical applications.
Am J Orthop 2006;35:285-291.

Question 34:

Options:

Full-length tibia-fibula radiographs
Inability to bear weight
History of recurrent ankle sprains
Presence or absence of medial tenderness
MRI scan

Correct Answer: Full-length tibia-fibula radiographs

Explanation:

The radiographs reveal a medial ankle injury with a widened medial clear space. No fibula fracture is visualized on this view; therefore, full-length radiographs looking for a proximal fibula fracture are required to determine treatment. The presence or absence of medial tenderness has been shown to not be a good predictor of unstable injuries. A history of previous injuries or ankle instability is typically lateral instability, which would not present with this radiographic appearance. An MRI scan can be used to evaluate subtle syndesmotic injuries, but there is a clear widening of the medial clear space in this case. The inability to bear weight is not helpful in determining the treatment options.
(SBQ12TR.24) In each of the following scenarios, atrophic fracture nonunion occurred after initial treatment with intramedullary nail fixation. Which scenario has shown to have the highest rate of osseous union if treated with exchange intramedullary nailing?
Oligotrophic nonunion of a comminuted humeral shaft fracture
Oligotrophic nonunion of a transverse humeral shaft fracture
Oligotrophic nonunion of an oblique distal femur fracture
Oligotrophic nonunion of a comminuted tibial shaft fracture
Oligotrophic nonunion of an oblique tibial shaft fracture
Reamed exchange nailing is recommended for the management of aseptic nonunions of noncomminuted tibial shaft fractures. Union rates have been reported between 76-96% in large studies.
Tibial exchange nailing promotes osseous bone healing of non-unions by providing biological and mechanical support. The biological support is provided by reaming the medullary canal. This increases periosteal blood flow and stimulates periosteal new-bone formation. The mechanical support is provided by a larger-diameter intramedullary nail, which increases the rigidity and strength of the nail.
Brinker et al. reviewed the concept of exchange nailing of nonunited long bone fractures. They showed that exchange nailing is the most successful in the treatment of nonunions following closed or open fractures without substantial bone loss. Aseptic, noncomminuted diaphyseal femoral and tibial shaft fractures showed the highest rates of union with exchange nailing, which were found to be 76-100% and 72-96%, respectively.
Illustration A shows a heterotrophic non-union of the tibia after intramedullary nailing. The patient was treated with exchange nailing with a larger nail. On the right shows a 4 month post-op radiograph after exchange nailing showing osseous union at the fracture site.
Incorrect Answers:
(SBQ12TR.79) A right-hand dominant female sustains a right proximal humerus fracture. The patient is provided a sling, and is recommended pendulum exercises with elbow range of motion to begin in 1 to 2 weeks. Which of the following would be an indication for surgical management?
Age greater than 70 years.
Fracture pattern in Figure A
Significant medical comorbidities.
Fracture pattern in Figure B
Fracture pattern in Figure C
The patient has been treated with non-operative management for her proximal humerus fracture. Operative management should be considered in patients with head splitting proximal humerus fractures and in those with dislocations that cannot be reduced.
Head splitting proximal humerus fractures should be treated with operative management. Open reduction internal fixation versus hemiarthroplasty are used to treat this type of fracture. Surgical management is also considered in proximal humerus fractures in young patients, in fractures where the greater tuberosity is
displaced >5 mm, and in proximal humerus fractures associated with humeral shaft fractures.
Koval et al. studied 104 patients with one-part proximal humerus fractures treated non-operatively, and found 80% with good or excellent results. They also found that 90% of patients treated non-operatively had either no or mild pain about the shoulder at follow-up.
Lefevre-Colau et al. performed a randomized prospective study on 74 patients with an impacted proximal humerus fracture. One group was treated with early mobilization of the shoulder (within 3 days after the fracture) while the other group was immobilized for 3 weeks followed by physiotherapy. They concluded that early mobilization was safe and allowed for quicker return to functional use of the affected limb.
Figure A shows an AP radiograph of a right minimally displaced greater tuberosity proximal humerus fracture. Figure B shows AP and axillary radiographs of a right head split proximal humerus fracture that is posteriorly dislocated. Figure C shows an AP radiograph of a right minimally displaced Salter Harris II proximal humerus fracture. Illustration A shows an AP radiograph of a left valgus impacted proximal humerus fracture with a greater tuberosity fragment displaced >5mm treated with ORIF.
Incorrect Answers:

Question 35:

Which of the following types of displaced posterior pelvic disruptions must undergo anatomic reduction and internal fixation to ensure the best clinical outcome?

Options:

Sacral fracture through the foramen
Sacral fracture through the ala
Sacroiliac joint dislocation
Reverse fracture-dislocation of the sacroiliac joint through the ilium
Iliac wing fracture

Correct Answer: Sacroiliac joint dislocation

Explanation:

Question 36:

Options:

replacement of the sling with a modified spica cast
open reduction and internal fixation
percutaneous pin fixation
arthroscopic labral repair
arthroscopy and removal of the loose fragment back answer Question 125.03

Correct Answer: open reduction and internal fixation

Explanation:

AM J Sports Med 1998;26:41-45 JBJS Am 1993;75:479-484
back to this question go to explanation

Question 37:

Options:

Osteochondroma
Enchondroma
Myositis ossificans
Parosteal osteosarcoma
Prior bony trauma

Correct Answer: Osteochondroma

Explanation:

DISCUSSION: The radiographs reveal a sessile lesion projecting from the medial aspect of the distal femur. The lesion shares the cortex with the bone and the base communicates with the medullary space of the femur. This is the classic appearance of an osteochondroma, the most common benign tumor of bone.
REFERENCES: Menendez LR (ed): Orthopaedic Knowledge Update: Musculoskeletal Tumors. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 103-111.
Parsons TW: Benign bone tumors, in Fitzgerald R Jr, Kaufer H, Malkani A (eds): Orthopaedics. Philadelphia, PA, Mosby International, 2002, pp 1027-1035.

Question 38:

What is the most common maxillofacial/dental injury in ice hockey?

Options:

Temporomandibular
Lip laceration
Tooth avulsion
Crown fracture
Mandible fracture

Correct Answer: Crown fracture

Explanation:

Question 39:

When compared to traditional open repair through a posterior incision, percutaneous Achilles tendon repair clearly results in a reduction of what complication?

Options:

Wound infection
Sural nerve injury
Achilles tendon re-rupture
Weakness
Deep venous thrombosis

Correct Answer: Wound infection

Explanation:

DISCUSSION: Prospective studies, including randomized and randomized multicenter reports, have shown that percutaneous or mini-open acute Achilles tendon repair has comparable functional results when compared to traditional open techniques. Calder and Saxby reported one superficial infection out of 46 patients with a mini-open repair; Assal and associates and Cretnik and associates had no wound complications or infections. The other complications have not proved to be less likely with the mini-open or percutaneous technique.
REFERENCES: Assal M, Jung M, Stern R, et al: Limited open repair of Achilles tendon ruptures:
A technique with a new instrument and findings of a prospective multicenter study. J Bone Joint Surg Am 2002;84:161-170.
Calder JD, Saxby TS: Early, active rehabilitation following mini-open repair of Achilles tendon rupture: A prospective study. Br J Sports Med 2005;39:857-859.
Cretnik A, Kosanovic M, Smrkolj V: Percutaneus versus open repair of the ruptured Achilles tendon: A comparative study. Am J Sports Med 2005;33:1369-1379.

Question 40:

A 60-year-old woman with rheumatoid arthritis has atlanto-axial instability and basilar invagination. What MRI findings would suggest the need for cervical fusion?

Options:

Cervical medullary angle of 125°
Space available for the cord of 15 mm
Cord diameter in flexion of 10 mm
C3-4 subluxation of 2 mm
Erosion of the tip of the odontoid

Correct Answer: Cervical medullary angle of 125°

Explanation:

DISCUSSION: The cervical medullary junction should be 135° or greater. An angle of 125° suggests compression of the cervical medullary junction. Other findings supporting surgical intervention include a cord diameter in flexion of less than 6 mm or less than 13 mm of space available for the cord.
REFERENCES: Clark CR (ed): The Cervical Spine, ed 3. Philadelphia, PA, Lippincott Williams & Wilkins, 1998, pp 700-701.
Monsey RB: Rheumatoid arthritis of the cervical spine. J Am Acad Orthop Surg
1997;5:240-248.
Bundschuh C, Modic MT, Kearney F, et al: Rheumatoid arthritis of the cervical spine: Surface-coil MR imaging. Am J Roentgenol 1988;151:181-187.

Question 41:

A 30-year-old patient is indicated for distal femoral osteotomy. This procedure results in survivorship with

Options:

a functional result for at least 20 years.
a functional result that deteriorates within the first 10 years.
an eventual conversion to a constrained knee arthroplasty.
an eventual need for arthrodesis.

Correct Answer: a functional result that deteriorates within the first 10 years.

Explanation:

DISCUSSION
Distal femoral varus osteotomy (DFVO) is intended for patients younger than age 50, more active patients with isolated lateral compartment arthritis and valgus malalignment. Although the knee functional score improves at 1-year follow-up, the function scores significantly deteriorate at 10-year follow-up. At 15-year follow-up, the knee function further declines, resulting in an overall failure rate of 48.5%. DFVO provides longer lasting benefit in patients with better presurgical knee function.
Total knee arthroplasty following DFVO provides improved function and successful outcomes. Standard posterior stabilized components provide satisfactory stability after appropriate ligament balancing without the need for stemmed or highly constrained implants for most patients.
CLINICAL SITUATION FOR QUESTIONS 65 THROUGH 67
Figures 65a and 65b are the radiographs of an 80-year-old woman with long-standing knee pain who has failed nonsurgical treatment that includes a structured physical therapy program, nonsteroidal anti-inflammatory medications, and intra-articular steroid injections. Her radiographs reveal significant degenerative changes. She has experienced some cognitive decline during the last several years and poorly tolerates pain medications, but she remains very active.

Question 42:

Options:

Valgus osteotomy
Removal of the hardware
Intramedullary fixation after removal of the hardware
Conversion to total hip arthroplasty with a long cementless stem
Conversion to total hip arthroplasty with a primary tapered stem

Correct Answer: Conversion to total hip arthroplasty with a long cementless stem

Explanation:

Question 43:

Which of the following lesions is best suited for autologous chondrocyte implantation?

Options:

Patellofemoral arthritis
Lateral femoral condylar arthritis
Medial femoral condylar arthritis
Medial femoral chondral defect
Medial femoral and tibial articular chondral matching defects

Correct Answer: Medial femoral chondral defect

Explanation:

Question 44:

Options:

core decompression.
biopsy of the femoral head.
protected weight bearing and observation.
total hip arthroplasty.
percutaneous cannulated pin fixation of the femoral neck.

Correct Answer: protected weight bearing and observation.

Explanation:

DISCUSSION: Transient osteoporosis of the hip is an uncommon problem, usually affecting women in the last trimester of pregnancy and middle-aged men. Symptoms include pain in the involved hip with temporary osteopenia; however, there is no joint space involvement. In this patient, the imaging findings are consistent with transient osteoporosis. Short TR/TE (repetition time/echo time) images reveal diffusely decreased signal intensity in the femoral head and intracapsular region of the femoral neck. Increased signal intensity is seen with increased T
2
-weighting. Within a few months, the pain, as well as the imaging findings, will completely resolve without intervention. Distinguishing the diffuse features of transient osteoporosis of the hip from the segmental findings of osteonecrosis is essential. Unlike transient osteoporosis of the hip, osteonecrosis will have a double-density signal on MRI and may progress radiographically. Surgical intervention and oral corticosteriods are not indicated for treatment. Protected weight bearing until the pain resolves may decrease symptoms while the transient osteoporosis resolves.
REFERENCES: Potter H, Moran M, Scheider R, et al: Magnetic resonance imaging in diagnosis of transient osteoporosis of the hip. Clin Orthop 1992;280:223-229.
Bijl M, van Leeuwen MA, van Rijswijk MH: Transient osteoporosis of the hip: Presentation of typical cases for review of the literature. Clin Exp Rheumatol 1999;17:601-604.
Montella BJ; Nunley JA, Urbaniak JR: Osteonecrosis of the femoral head associated with pregnancy: A preliminary report. J Bone Joint Surg Am 1999;81:790-798.

Question 45:

0 sustained a subcapital fracture of her hip. She is an avid tennis player, and history reveals no previous fractures. What is the most appropriate follow-up care? Review Topic

Options:

Antiresorptive bisphosphonate medication
A repeat dual-energy x-ray absorptiometry scan (DEXA) and treatment if the T-score is less than -2.5
A repeat DEXA scan and treatment if the T-score is greater than -1.5
No treatment since the BMD is not in osteoporotic range
(PTH) taraparatide hormone followed by surgery

Correct Answer: Antiresorptive bisphosphonate medication

Explanation:

Question 46:

Synovitis of the MTP joints with eventual hyperextension deformity of the MTP is a common toe deformity seen with RA.

Options:

Genetic polymorphisms in all of the following genes are associated with osteoporosis EXCEPT?
Calcitonin receptor
Estrogen receptor-1
Vitamin D receptor
Type I collagen alpha-1 chain
Cartilage oligomeric matrix protein (COMP)

Correct Answer: Calcitonin receptor

Explanation:

Polymorphisms in the genes for the calcitonin receptor, estrogen receptor-1, vitamin D receptor, and the type I collagen alpha-1 chain (along with over 45 other genes) have been shown to be associated with osteoporosis. Answer 5, Cartilage oligomeric matrix protein, shows no current association with osteoporosis, but is the known genetic mutation associated with multiple epiphyseal dysplasia (a frequently tested fact). No single cause for osteoporosis has been shown at this point in time.
Jin et al conducted a meta-analysis regarding polymorphisms in the 5' flank of COL1A1 gene and the conflicting results relating to osteoporosis. They found that the COL1A1 Sp1 polymorphism is associated with a modest reduction in BMD and an increased risk of fracture.
The attached review by Huang and Kung discusses the multiple genetic and environmental determinants of osteoporosis and illustration A (from a different review by these same authors) lists the known genes currently associated with osteoporosis.
The greatest biomechanical difference between unicortical and bicortical locking screws is seen when what force is applied?
Compression
Torsion
Distraction
Bending on the side of the plate
Bending on the surface perpendicular to the plate
Torsion force has the largest biomechanical difference between unicortical locked screws and bicortical locked screws.
The first referenced article by Roberts et al noted that by replacing the farthest unicortical
screws (3 per side of the fracture) with bicortical locking screws, torsion resistance was increased by over 50%.
The second referenced article by Fulkerson et al noted decreased resistance to all applied forces with unicortical screws in a comminuted fracture model, and recommended against their use in such a fracture.
FOR ALL MCQS CLICK THE LINK ORTHO
MCQ BANK
You are planning surgery on a 54-year-old female with the tibial plateau fracture seen in figures A and B. After reduction of the joint surface you plan to fill the void with a bone-graft substitute to prevent joint collapse. Which of the following bone-graft substitutes
disappears most quickly in vivo?
Collagen-based matrices
Calcium phosphate
Calcium sulfate
Synthetic calcium sulfate and tri-phosphate mixture
Coraline hydroxyapatite
Calcium sulfate disappears in vivo quickly, usually within 4-12 weeks. Calcium phosphate and coraline hydroxyapatite are resorbed slowly, somewhere between 1-10 years, depending on the manufacturer. Synthetics that combine calcium sulfate and phosphate
resorb quicker than calcium phosphate but slower than calcium sulfate. Collagen-based matrices show quick resorption of the collegen but slow resorption of their hydroxyapatite coating. Walsh et al. examined the in vivo response of calcium sulfate pellets alone or in combination with autogenous bone graft in a sheep model. They found excellent bone formation in defects filled with calcium sulfate pellets. Immunostaining for various cytokines (BMP-2, BMP-7, PDGF, or TGF-beta)
showed elevated levels in the newly formed bone. They proposed that the local environment acidity was responsible for breakdown of the calcium sulfate. Watson evaluated 8 patients with comminuted tibial metaphyseal fractures treated with an injectable calcium sulfate. They found that bone regrowth was observed in all patients and the bone substitute almost completely resorbed by
months. Bucholz reviewed the biochemical, biomechanical, and longevity characteristics of the common bone substitutes.
Which of the following Figures shows a fixation construct achieving absolute stability?
Figure A shows percutaneous pinning, Figure B shows locked bridge plating, Figure C shows intramedullary nailing, Figure D shows lag fixation and neutralization plating, and Figure E shows external fixation. All except Figure D show relative stability constructs.
Absolute stability is a construct seen in Figure D, where lag screws and a neutralization plate are shown in a postoperative clavicle. No micromotion is seen with this technique, and healing is by primary (Haversian) healing, as opposed to the other four constructs, which have relative stability and heal via callus formation. The first reference, the AO Principles textbook, covers this in depth.
The second reference by Claes et al notes that bone can still heal with bone (as opposed to fibrous union) with strain rates up to 15%.
Which immunoglobulin subtype does the rheumatoid factor target?
IgA
IgE
IgM
IgG
Rheumatoid factor does not target an immunoglobulin
Rheumatoid factor is an auto-antibody most commonly seen with rheumatoid arthritis. The presence of rheumatoid factor can also indicate generalized autoimmune activity unrelated to rheumatoid arthritis (e.g. tissue or organ rejection). Rheumatoid factor is itself an IgM antibody that is directed against the Fc portion of IgG antibody. Rheumatoid factor (IgM) attaches to IgG to form immune complexes which are deposited in tissues like the kidney and contribute to the overall disease process in rheumatoid arthritis.
James et al. assessed the occurrence and predictive factors for orthopaedic surgery in an cohort of patients with rheumatoid arthritis. Risk factors for surgery varied but the authors found that decreased inflammatory markers during the first year after diagnosis decreased the risk for subsequent surgery.
The positive predictive value is defined as which of the following?
True positives / (true positives + true negatives)
False negatives / (false negatives + true positives)
False positives / (false positives + false negatives)
(True positives + false positives) / (true negatives + false negatives)
True positives / (true positives + false positives)
Corrent answer: 5
The positive predictive value is defined as the true positives divided by the sum of the positive results (true positive and false positive). It is also defined as the probability that a patient with a positive test actually has the disease; it is dependent on prevalence of disease.
The referenced articles by Wojtys and Kuhn et al are two of a series of medical statistics review papers.
An 85-year-old woman undergoes the treatment seen in Figure A for a displaced left femoral neck fracture. During wound closure, the patient becomes hypoxic and hypotensive. Despite aggressive resuscitation efforts, she passes away three hours later in the intensive care unit. The autopsy findings seen in
Figure B from the patient's lungs are most likely the result of which of the following
Reaming for the femoral component
Insertion of a femoral component after cement pressurization
Utilization of undersized broaches during canal preparation
Inadequate beta blockade
Use of spinal anesthesia
The clinical scenario is consistent with fat emboli syndrome. Figure A, shows a cemented bipolar hemiarthroplasty while Figure B shows marrow embolization into the lungs.
Studies have shown that intramedullary pressure and fat embolization are greatest during pressurization of cement and implant insertion.
Intramedullary pressure is influenced by size, shape, sharpness and insertion rate of an implant. Pressurization during cementing of a femoral component generates a large degree of pressure over a much wider surface area than in the other methods described of femoral canal instrumentation or preparation, as the entire femoral canal is
pressurized at one time. This results in the highest degree of marrow embolization to the lungs resulting in hypoxia.
Dobrjanski et al studied which variables affected intramedullary pressurization and found that lower implant insertion speed, lower hammering force, a
rubber- compared with steel-tipped hammer and a larger synthetic bone-to- implant radial gap reduced intramedullary pressure generated in a femur module.
Sustained compression applied to a growth plate under experimental conditions has what effect?
No effect
Accelerated longitudinal growth
Decelerated longitudinal growth
Decelerated apposition growth
Decreased bending strength of the bone
The Heuter-Volkmann Law states that compression across the growth plate slows longitudinal growth.
Stokes et al demonstrated that sustained compression across the growth plate can decrease longitudinal growth by 40%. Tension across the physis increases growth, but to a lesser degree.
A 13-year-old girl with a displaced proximal tibia fracture is brought into the emergency department by her adult cousin. The
fracture needs surgical management. The child is living with her cousin's family while her parents are in Germany. While the child speaks fluent English, her cousin and her parents are German-only speaking. How should you consent this patient?
No consent is needed given the urgent nature of the injury, proceed with surgery
Talk with the cousin, using the child as a translator
Talk with the cousin, using a German-translator
Call the parents in Germany, using the child as a translator over the phone
Call the parents in Germany, using a German-translator over the phone
This is an urgent (not emergent) clinical senario, and as such, the child needs to have
formal consent by speaking with her parents using a German- translator.
Wenger and Lieberman discuss the problems and potential solutions surrounding the process of informed consent in patients who either personally lack capacity to make decisions or in patients who require surrogates (like minors) to make treatment decisions.
Lindseth reviews the ethical issues encountered in pediatric orthopaedics and the problems associated with these decisions. Specifically pediatric consent is confounded because the person giving the consent is not the person who will bear the consequences of the treatment.
What is the primary mode of bisphosphonate excretion?
Renal
Gastrointestinal
Liver
Skin
Pulmonary
Bisphosphonates are a broad class of medicines used to treat osteoporosis and Paget's disease. They work by inhibiting osteoclast-mediated resorption after being absorbed into the inorganic phase of bone and taken up by osteoclasts. The paper by Lin et al provides a nice review of bisphosphonates and describe their appropriate use in enhancing bone density in patients with structurally
flawed bone. They describe the mechanism of action of bisphosphonates as pyrophosphate analogues and their renal mechanism of excretion, thus, prohibiting their use in patients with renal insufficiency. Rosier discusses the role of the orthopaedic surgeon in the diagnosis and treatment of patients with osteoporosis, now referred to as the "own the bone" initiative. Central to the treatment of osteoporosis are bisphosphonates and the anti-RANKL
monoclonal antibody, Denosumab.
The 2009 AAOS Clinical Guideline on prevention of pulmonary embolism in patients undergoing total hip or knee arthroplasty recommends classifying patients as having either a "standard" or "elevated" risk of bleeding complications. The presence of all of the following qualify a patient as having an "elevated" risk of major bleeding EXCEPT?
History of hemophilia
History of protein C deficiency
History of a recent gastrointestinal bleed
History of a recent hemorrhagic stroke
History of Von Willebrand's Disease
The 2009 AAOS Clinical Guideline on prevention of pulmonary embolism in patients undergoing total hip or knee arthroplasty recommends that all patients pre-operatively should be classified as either having an elevated or standard risk of bleeding and either an elevated or standard risk of pulmonary embolism.
A history of a bleeding disorder (e.g., hemophilia, Von Willebrand's Disease), recent GI bleed, or hemorrhagic stroke qualifies a patient as having an elevated risk of major bleeding.
A history of hypercoagulable state (such as protein C deficiency) or previous documented pulmonary embolism qualifies a patient as having an elevated risk of pulmonary embolism. Type of thromboembolism prophylaxis is recommended by weighing risk of major bleeding vs risk of PE. For those patients with a known contraindication to anticoagulation an IVC filter is considered. Mechanical prophylaxis is recommended across all risk (low to
high risk of either bleeding or pulmonary embolism) groups undergoing total hip or total knee arthroplasty. The detailed AAOS guidelines can be found on the AAOS website.
The evidence based clinical recommendations are presented in the reference by Johanson et al.
In consideration of a prosthetic knee, each of the following are advantages of choosing a polycentric knee with fluid control over a constant friction knee EXCEPT:
Allows variations in cadence
Flexes in a more controlled manner
Lighter in weight
Improved stance control allows less energy expenditure
Overall length of the limb is shortened during initiation of a step reducing the risk of stumbling
Single axis, constant friction knees function as a simple hinge. They are light, durable, and much cheaper prostheses making them ideal for growing children who will need multiple prostheses before reaching adulthood. This prosthesis allows only a single speed of walking, and relies solely on alignment for stance phase stability. Polycentric knees offer each of the advantages stated above making it a more ideal prosthesis for the active adult. Disadvantages of the polycentric knee include cost, weight, and more sophisticated maintenance.
Tang et al reviews the current prosthetic options for leg and foot amputees. Illustration A demonstrates a single axis knee prosthesis.
Illustration B demonstrates a polycentric knee prosthesis.
Which of the following biologic agents commonly used to treat rheumatoid arthritis (RA) DOES NOT target tumor necrosis factor- alpha (TNF-alpha)?
Infliximab
Rituximab
Etanercept
Golimumab
Adalimumab
Rituximab is a chimeric monoclonal antibody against the protein CD20, which is primarily found on the surface of immune system B cells. Rituximab is used in combination with methotrexate to treat RA that has not responded to one or more types of treatment, including anti-tumor necrosis factor (TNF) blockers.
In rheumatoid arthritis, and other chronic inflammatory conditions, cytokines produced by activated T-cells/macrophages contribute to the pro-inflammatory state. TNF-alpha is thought to be one of the major cytokines involved in rheumatoid arthritis pathology. As a result, many biologic agents used to treat RA are directed towards blocking TNF-alpha or its receptors. These drugs are able to reduce inflammation and stop disease progression.
Elliot et al. evaluated the safety and efficacy of infliximab in 20 patients with active RA in an open phase I/II trial lasting 8 weeks. They found that treatment with anti-TNFa was safe, well tolerated and resulted in significant clinical and laboratory improvements.
Illustration A depicts five commonly used anti-TNF alpha biologic agents for the treatment of rheumatoid arhtirits with their usual dosing regimens.
Incorrect Answers:
Receptor activator of nuclear-factor kappa-B ligand (RANKL) is
an important regulator of bone resorption. Which of the following cells is the MAJOR source of RANKL in bone remodelling?
Osteoclasts
Osteoblasts
Integrins
T cells
Macrophages
RANKL, a key osteoclastogenic protein, is expressed by osteoblasts and binds to the RANK receptor on osteoclast precursor cells.
The binding of RANKL to RANK on osteoclast precursor cells drives their differentiation into mature osteoclasts (multinucleated giant cells). Mature osteoclasts bind to the bone surfaces via integrins and resorb bone via their ruffled border within Howship's lacunae. Osteocytes orchestrate bone resorption and bone deposition by controlling osteoclast and osteoblast activity. Osteoblasts release RANKL to induce osteoclast differentiation, while
osteoblasts release osteoprotegerin (OPG) to downregulate osteoclastogenesis. Osteocytes also release fibroblast growth factor-23 (FGF-23), BMPs and sclerostin to regulate osteoblast activity. Antibodies to RANKL and Sclerostin have both been shown to increase bone density.
Compton et al. reviewed osteocyte function and the emerging importance of sclerostin, which is a glycoprotein. Sclerostin is predominantly secreted by osteocytes under physiologic conditions to act as an important negative regulator of bone mass through inhibition of bone formation by osteoblasts.
Illustration A demonstrates local bone milieu. It depicts the interplay between osteocytes, osteoblasts, and osteoclasts via the factors described above.
Incorrect answers:
A 45-year-old woman with rheumatoid arthritis is being scheduled for a total knee athroplasty in 2 weeks. She is currently taking sulfasalazine, Penicillamine, and etanercept, a tumor necrosis factor inhibitor (aTNF-a). What changes should be made to her medication regimen prior to surgery?
Discontinuation of all three medications 1 weeks prior to surgery
Discontinuation of sulfasalazine 1 weeks prior to surgery, continuation of etanercept and penicillamine
Continuation of sulfasalazine, penicillamine, and etanercept
Continuation of sulfasalazine and penicillamine, discontinuation of etanercept 1 week prior to surgery
Continuation of penicillamine, discontinuation of sulfasalazine and etanercept 1 week prior to surgery
Anticytokine disease-modifying antirheumatic drugs (DMARD) have become increasingly popular in the treatment of RA. Immunosuppression and the risk of infection are potential complications for all anti-TNF-alpha medications. Current recommendations for cessation of immunosuppressive therapy are when the drug concentrations are at their lowest levels which include the following: 3 days after etanercept injection; 2 weeks prior to infliximab infusion; 10 days after adalimumab injection. Medications such as sulfasalazine and penicillamine may be continued during the pre and post- operative period. Recent evidence and guidelines such as those reviewed by Keith's paper, suggest that anti-TNF-alpha medications should be stopped 4 weeks prior to surgery.
Giles et al report in their case control series an increased infection rate of RA patients undergoing an orthopaedic procedure who were on TNF-a inhibitors as opposed to patients on more traditional treatment regimens like methotrexate and prednisone.
Which of the following supplements affects blood clotting through its effect on platelets?
Ginkgo
Vitamin D
Ephedra
St. John's Wort
Selenium
Ginkgo and ginseng are two common supplements used in the general population that have inhibitory effects of platelet function. Adverse peri- operative complications consisting of increased bleeding and hematoma formation have been reported with the use of these two herbal supplements. The most commonly used supplements that could have an effect in the peri- operative period include echinacea, ephedra, garlic, ginkgo, ginseng, kava, St John's wort, and valerian. Bleeding has been shown to be effected by garlic, ginkgo, and ginseng; cardiovascular instability from ephedra; and hypoglycemia from ginseng. Kava and valerian have pharmacodynamic herb- drug interactions that can increase the sedative effect of anesthetics. St John's wort has been shown to alter the metabolism of certain drugs used in the perioperative period.
Ang-Lee et al review common supplements used today and their potential anesthesia/operative effects. The article places emphasis on proper history taking of not only medications but also supplements which is often times left out of documentation.
The femur radiograph of a healthy 25-year-old female is compared to the femur radiograph of a healthy 85-year-old female. Which of the following best describes the 25-year-old's femur?
Increased cortical thickness and a smaller medullary canal volume
Decreased cortical thickness and a larger medullary canal volume
Equivalent cortical thickness and medullary canal volume
Increased cortical thickness and larger medullary canal volume
Decreased cortical thickness and a smaller medullary canal volume
As the human body ages the cortical thickness/area decreases and subsequently the diameter/volume of the medullary canal increases. Therefore, a young healthy 25- year-old woman should have thicker cortices and a smaller medullary canal volume than her counterpart at 85 years. A decreased cortical bone area is linked to increased fracture risk.
Stein et al studied femurs from subjects aged 21-92 years of age. They found that a reduction in cortical area was seen in older specimens and this change was more
pronounced in female specimens.
Wrong Answers:
Which of the following is NOT a described complication of corticosteroid injections?
Local flare in surrounding tissues
Apoptosis of myocytes
Skin pigmentation changes
Fat atrophy
Facial flushing
Corticosteroids have not been shown to cause apoptosis of myocytes when injected extra-articularly. Each of the other answers have been described.
Cole and Schumacher provide a review of current uses of corticosteroid injections, and emphasize that how accurately the injection is placed affects the outcome.
Kumar and Newman report prospectively on 672 patients who received 1147 intra- and extra-articular injections. Their overall complication rate was low (16%) with injection site pain (mild) and bleeding constituting the majority of cases. There were 4 instances of fat atrophy in the extra-articular group, and
cases of syncope or dizziness in the intra-articular group. They did not discuss the efficacy of their injections.
A surgeon chooses a periarticular locking plate with unicortical proximal locking screws for an extra-articular distal femur fracture as seen in Figure A. Compared to an identical construct with bicortical unlocked proximal screw fixation, the periarticular locking plate with unicortical locking screws has which biomechanical properties?
Greater torsional and axial fixation strength
Less torsional but greater axial fixation strength
Equal torsional and axial fixation strength
Greater torsional but less axial fixation strength
Less torsional and axial fixation strength
Unicortical locking plates have characteristically less torsional strength than bicortical locking plates and bicortical non-locking plates. Axial strength is improved with locking plate fixation.
Zlowodzki et al studied the LISS periarticular locking plate with unicortical proximal fixation in a distal femur model and found superior axial fixation strength (134%) but worse torsional strength (68%) compared to a fixed angle blade plate with non- locking bicortical screw fixation.
Locked plating was reviewed by Haidukewych and Ricci which highlighted the added cost, unique complications, and they recommended the use of locked plating only in situations when unlocked constructs have demonstrated poor outcomes.
In rat models looking at the effect of malnutrition on fracture healing, amino acid supplementation in a nutritionally deprived rat increases all of the following EXCEPT
Serum albumin
Body mass
Quadriceps total protein content
Fracture callus mineralization
Insulin-like growth factor 1 (IGF-1) mRNA expression
The study by Hughes et al found that essential amino acid supplementation (glutamine, arginine, and taurine) following femoral fracture in a protein- malnourished rat model increases serum albumin, body mass, quadriceps total protein content, and fracture callus mineralization. Expression of IGF-1 and
IGF-2, myosin, actin, and VEGF mRNA were all significantly decreased in the amino acid supplemented group compared to the malnourished group. The malnourished group is thought to have upregulation of mRNA expression in attempt to increase the amount of protein product that is translated, however the lack of amino acid building blocks in the malnutrition group was a barrier to appropriate protein synthesis.
The study by Day et al created a malnourished rat femur fracture model by administering a 6% protein diet. They found that administering a 20% protein diet in the post-fracture period yielded a greater cross-sectional area of the
fracture callus and callus stiffness compared to the 6% protein malnourished group.
The statistical power of a study is best defined by?
1 - probability of type-II (beta) error
True positive/(true positive + false negative)
True negative/(false positive + true negative)
1 - probability of type-I (alpha) error
[True positive/(true positive + false negative)] / false-positive rate
The power of a study is an estimate of the probability of finding a significant association in a research study when one truly exists. The power is defined by
1 - probability of type-II (beta) error, and is often set at 80%. For example, a power of 80% means that if the intervention works, the study has an 80% chance of detecting this and a 20% chance of randomly missing it. A type-II or beta error occurs when one falsely concludes that there is no significant association when there actually is an association (resulting in a false-negative study that rejects a true alternative hypothesis). The type-II or beta error can be determined if Type I error rate and sample size are known. A type-I or alpha error occurs when a significant association is found when there is no true association (resulting in a false-positive study that rejects a true null hypothesis). The alpha level refers to the probability of a type-I (alpha) error and is usually set for most studies at 0.05. Answer 2 is the formula for sensitivity. Answer 3 is the formula for specificity. Answer 5 is the formula for the positive likelihood ratio. The references by
Kocher and Wojtys are excellent reviews of basic biostatistic principles.
A 55-year-old female with a history of metastatic breast cancer develops shoulder pain without any trauma. Which of the following is involved with the findings shown in Figures A and B?
IL-4
RANK
TNF-alpha
OPG
Sox-9
Osteoclastic bone resorption is the final common mechanism for osteolysis, whether due to a pathologic lytic lesion, macrophage activation in particle wear, or normal remodeling. The RANK-RANKL mechanism controls the coupling of osteoblast and osteoclast activation. Figures A and B show an osteolytic lesion in the humerus in a patient with known metastatic breast carcinoma.
RANKL is expressed from osteoblasts and bone-marrow stromal cells. When RANKL binds to the RANK receptor (receptor/activator of NF-[kappa]B) on the cell membrane of osteoclasts it stimulates differentiation from osteoclast progenitor cells to mature osteoclasts. Mature osteoclasts proceed with osteoclastic bone resporption.
Osteoprotegerin (OPG) acts as a decoy receptor by binding to RANKL and blocking the interaction between RANKL and the RANK-receptor and consequently inhibiting osteoclast formation and
activation.
Illustration A depicts the RANK/RANKL involvement in tumor metastatic spread.
Laboratory values of a normal serum calcium and parathyroid hormone can be found in which of the following disease states?
Primary hyperparathyroidism
Type I vitamin D deficient rickets
Type II vitamin D deficient rickets
X-linked hypophosphatemic rickets
Nutritional rickets
Hypophosphatemic rickets is caused by the inability of kidney proximal tubules to reabsorb phosphate due to a mutated PHEX gene, found on the X chromosome. PHEX is thought to protect extracellular matrix glycoproteins from proteolysis. Hypophosphatemic rickets shares many clinical similarities with nutritional rickets but shows PTH levels that are not elevated, even with calcium and phosphate abnormalities.
Pettifor reviews the advances in molecular genetics in the understanding and possible treatments in tumour-induced osteomalacia/rickets.
The review article by Carpenter discusses the X-linked disorder including its clinical manifestations, the wide spectrum of disease severity, and complications of the disease in adult patients.
Illustration A is a table that details the laboratory values associated with each type of rickets.
An 80 year-old female undergoes ORIF of her hip fracture without any complications. A hospitalist consult was obtained for medical clearance pre- operatively, and she was diagnosed with osteoporosis. Which of the following treatment scenarios will lead to the best management of the patient's osteoporosis?
Schedule a follow-up appointment with the patients primary care physician to initiate therapy
Order a physical therapy consult and initiate an exercise plan
Have the patient meet with a nutritionist to increase her calcium and vitamin D intake
Start bisphosphonates, and have the patient follow-up with her primary care physician
Perform a metabolic work-up as an inpatient, and set-up an appointment in an osteoporosis clinic
The initiation of appropriate osteoporosis treatment following hip fractures occurs at a surprisingly low rate. Physical therapy and dietary changes are not appropriate initial treatments for osteoporosis, and bisphosphonate therapy should be prescribed by the physician who will be following and managing the patient's osteoporosis.
Miki et al performed a prospective randomized trial where they compared the rates of osteoporosis treatment initiation. The percentage of patients who were on pharmacologic treatment at 6 months post-injury was 58% in the group whose treatment was directed by the orthopedic surgeon and osteoporosis clinic, and 29% when managed by the primary care physician alone.
The elements chromium, molybdenum, and cobalt are basic components of which of the following implant materials?
Aluminum oxide
Cobalt alloy
Stainless steel
PMMA
Tantalum
Cobalt alloys are extremely strong and are well-suited to applications requiring longevity. Strength of the implant is improved by the addition of molybdenum. Corrosion resistance is addressed by the addition of chromium, which also increases the hardness of the implant.
Incorrect Answers:
Which of the following scenarios of treatment of a humerus fracture best achieves low strain at the fracture site and high stiffness of the treatment construct?
Functional bracing of a transverse midshaft fracture
Comminuted midshaft fracture with locked bridge plating
Short oblique fracture with interfragmentary lag screw and locked neutralization plate
Uniplane external fixation of a spiral open fracture
Oblique fracture with intramedullary nail fixation
Strain in fractures is calculated by dividing the interfragmentary movement by the size of the fracture gap. Strain must be very low (2%) for primary bone healing to occur, and should be less than 10% for secondary bone healing to occur. Stiffness refers the ability of the construct to resist movement under applied loads. Answer 3 describes a situation where primary bone healing is
the goal. For this to occur, there must be no significant gapping at the fracture site, there must be low strain between fracture fragments, and the construct must be stiff.
None of the other answers would accomplish this. Functional bracing and intramedullary fixation both accomplish healing through formation of fracture callus, or secondary healing. A comminuted fracture treated with locked bridge plating relies on less stiffness to allow for secondary healing between fragments. However, since there are many fracture fragments, the strain is distributed among them and therefore remains low. A uniplane external fixator is very unlikely to accomplish low strain and high stiffness in this setting.
A 67-year-old man complains of low-grade fevers and calf pain 2 weeks following a total knee arthroplasty. What is the next appropriate step in management of this patient?
Plethysmography of lower extremity
MRI of lower extremity
CT angiography of lower extremity
Venous ultrasonography
Knee aspiration to evaluate for septic joint
Venous ultrasonography is the next best step in this patient's management, due to the clinical picture of a deep venous thrombosis. The most sensitive and specific recommended diagnostic procedure is a venous ultrasonography.
In their multi-center study, Haut et al. hypothesized that admission to trauma centers that use duplex ultrasound more frequently would independently predict increased DVT reporting for individual patients. They indeed found that trauma centers ultrasound practice was an independent predictor of DVT diagnosis for individual patients, controlling for patient-level risk factors, but concluded the elevated DVT rates at these centers were due to surveillance bias. As such, they recommend that surveillance for DVT should not be considered as a quality control measure in the care of trauma patients.
A patient undergoes closed reduction of a bimalleolar ankle fracture dislocation by the ER physician and is sent to your clinic for evaluation. You evaluate the patient and schedule him for surgery. According to the 2009 guidelines, which of the following scenarios would meet criteria for coding the encounter as a new patient?
You injected his knee in the office almost 3 years ago for osteoarthritis, and have not seen him since
He had an arthroscopic operation by your partner 4 years ago
You were consulted 1 year ago for shoulder pain when he was hospitalized for chronic renal failure
He was seen by your partner in clinic for a herniated disk 2 years ago, but had no procedures performed
You performed a hip replacement on him 12 years ago, and his last follow- up was 18 months ago at which time he was doing well
Only answer two is correct. The 2009 guidlines clarify that the patient can be defined as new only if he has not been seen by anyone in the physician's same group practice and of the same specialty in the past 3 years. Hand and sports medicine specialists with a CAQ, however, are an exception and are allowed to bill for patients already seen by other orthopedists in the same group as new
patients. This scenario would not qualify as a consultation, since the orthopedic surgeon
is taking over care of the patient's problem and is not merely offering advice to another physician who is already caring for the patient. Consultations do not have the same 3 year time qualification. However, Medicare and many other insurers no longer recognize consultation codes.
All the following medications binds reversibly to the enzyme COX-1 EXCEPT
Meloxicam
Diclofenac
Indomethacin
Naproxen sodium
Aspirin
Aspirin binds irreversibly to the cyclooxygenase enzyme. Aspirin acetylates platelet cyclooxygenase and permanently inhibits thromboxane (TX) A2 production leading to its antiplatelet effects. The other NSAID's listed above bind reversibly with COX-1.
Patrono et al discuss the pharmokinetics and platelet effect of both low dose and regular dose aspirin. Nonsteroidal anti-inflammatory drugs compete dose- dependently with arachidonate for binding to platelet cyclooxygenase.
In the treatment of patients with rheumatoid arthritis, TNF-alpha is blocked by which of the following agents?
Tocilizumab
Anakinra
Etanercept
Abatacept
Rituximab
Etanercept is a biochemically designed soluble p75 tumor necrosis factor receptor immunoglobulin G fusion protein, which blocks the downstream
effects of TNF.
Methotrexate is a chemotherapy agent used to inhibit lymphocytes. Gold inhibits monocytes, while sulfasalazine is an anti-inflammatory decreasing the production of
prostaglandins and leukotrienes. Rituximab inhibits B-cells as it
is a monoclonal antibody to CD20 antigen. Anakinra (Kineret) is a recombinant IL-1 receptor antagonist. Abatacept (Orencia) is a selective costimulation modulator that binds to CD-80 and CD-86 (inhibits T cells). Tocilizumab (Actemra)is an IL-6 receptor inhibitor (2nd line treatment for poor response to TNF-antagonist therapy).
Pisetsky wrote an editorial in NEJM discussing the development of TNF blockers through research, and the potential for the use of Etanercept in patients with juvenile RA through its inhibition of lymphotoxin-alpha.
Which of the following medications when combined with methotrexate has been shown to be more effective than methotrexate alone in the treatment of rheumatoid arthritis?
Nitrofurantoin
Rifampin
Azithromycin
Erythromycin
Doxycycline
Tetracycline was initially used in the treatment of rheumatoid arthritis (RA) because Mycoplasma was thought to be the causative agent. It was later found that tetracyclines have biologic effects on the inflammatory and immunologic cascade by inhibiting collagenase activity. Collagenase is an enzyme involved
in breaking down macromolecules in the connective tissue, contributing to the pathologic changes of RA.
In a prospective study, O'Dell et al found that initial therapy with methotrexate plus doxycycline was superior to treatment with methotrexate alone. Furthermore, similar results for low-dose and high-dose doxycycline suggested that antimetalloproteinase effects were more important than the antibacterial effects.
When using C-arm fluorocopy, patient radiation exposure will be increased with which of the following?
The extremity is positioned closer to the image intensifier
A larger body part is imaged compared to a smaller body part
Use of radiation beam collimation
Mini C-arm fluroscopy is used instead of large C-arm fluroscopy
Decreased duration of imaging
Patient radiation exposure will be increased if a larger body part is imaged compared to a smaller body part.
The first study by Giordano et al used radiation dosimeters for large and mini c-arm machines. They found that elevated exposure levels can be expected when larger body parts are imaged, when the extremity is positioned closer to the x-ray source, and when the large c-arm is used over the mini c-arm.
The second study by Giordano et al also used dosimeters for a mini c-arm and found that the surgical team is exposed to minimal radiation during routine
use of mini-c-arm fluoroscopy, except when they are in the direct path of the radiation beam. They list factors to decrease radiation exposure to patient and surgeon including: minimizing exposure time, reducing exposure factors, manipulating the x-ray beam with collimation, orienting the fluoroscopic beam in an inverted position relative to the patient, strategic positioning of the surgeon within the operative field, judicious use of protective shielding during imaging, and maximizing the distance of the surgeon from the radiation beam.
Illustration A shows that arrangement #1 has the body part half-way between the radiation source and image intensifier. Arrangement #2 has the the image intensifier acting as an arm table for the body part with the radiation source further away. Arrangement #1 has more radiation exposure than #2. The distance between the x-ray tube and the body part is doubled in arrangement
#2 compared to arrangement #1. This increased distance correlates to a reduction in exposure according to the inverse square law (reduction in radiation intensity with greater distance from the x-ray source).
You are seeing a 13-year-old girl for asymptomatic flat feet and recommend observation. In educating this patient/family about general bone health, you recommend what amount of daily dietary calcium for your patient?

Question 47:

Options:

Quicker time to union
Decreased risk of malunion
Decreased risk of compartment syndrome
Decreased risk of shortening
Quicker return to work

Correct Answer: Quicker time to union

Explanation:

Question 48:

Options:

Acromial fracture
Humeral stress fracture
Acromioclavicular joint separation
Fracture of the surgical neck of the scapula
Triceps avulsion fracture

Correct Answer: Humeral stress fracture

Explanation:

Question 49:

Options:

Osteochondroma
Osteoblastoma
Osteomyelitis
Heterotopic ossification
Parosteal osteosarcoma

Correct Answer: Heterotopic ossification

Explanation:

Question 50:

Options:

failure to place a hard cervical collar.
helmet removal prior to examination.
transfer to a spine board prior to transport.
log-rolling the athlete to the supine position.

Correct Answer: helmet removal prior to examination.

Explanation:

Question 51:

A 36-year-old recreational tennis player sustains the injury shown in Figure 16. Management should consist of

Options:

observation.
rehabilitation.
immobilization.
primary repair.
reconstruction.

Correct Answer: primary repair.

Explanation:

Question 52:

The use of nonsteroidal anti-inflammatory drugs following femoral nailing has been associated with which of the following?

Options:

Increased rate of nonunion
Decreased narcotic requirements
Faster time to union
Increased rate of heterotopic ossification
Decreased rate of revision surgery

Correct Answer: Increased rate of nonunion

Explanation:

Question 53:

A 12-year-old girl is seen for left ankle pain. Radiographs reveal osteochondritis dissecans (OCD) involving the talus. What should the parents be told regarding management?

Options:

No treatment is required because spontaneous healing is common.
Nonsurgical management typically relieves pain and results in radiographic healing in less than 12 weeks.
Nonsurgical management frequently relieves pain but often may not result in radiographic healing even 6 months after treatment.
Hyperbaric oxygen treatment is helpful.
Ankle fusion is frequently necessary.

Correct Answer: Nonsurgical management frequently relieves pain but often may not result in radiographic healing even 6 months after treatment.

Explanation:

Question 54:

The injection shown in Figures 1a and 1b would most benefit a patient who reports which of the following symptoms? Review Topic

Options:

Dorsal foot pain extending into the great toe
Foot pain extending along the lateral border of the foot
Pain extending into the foot in a stocking distribution
Anterior thigh and shin pain ending at the ankle
Lateral foot paresthesias

Correct Answer: Dorsal foot pain extending into the great toe

Explanation:

Question 55:

Options:

ACL injuries are more common in men younger than 30 years of age.
ACL injuries are more common in women younger than 30 years of age.
ACL injuries are usually the result of contact sports.
The incidence of ACL injuries can be decreased by a neuromuscular training program.
ACL injuries are rarely associated with meniscal injury.

Correct Answer: ACL injuries are more common in women younger than 30 years of age.

Explanation:

Question 56:

Options:

Percutaneous pinning of the fracture with Kirschner wires
Open reduction and pinning with Kirschner wires
Arthroscopic in situ compression screw fixation
Reduction and compression screw fixation via a volar approach
Reduction and compression screw fixation via a dorsal approach

Correct Answer: Reduction and compression screw fixation via a dorsal approach

Explanation:

DISCUSSION: Displaced fractures of the scaphoid are best treated with compression screw fixation. Proximal third fractures (as in this patient) are optimally approached via a dorsal approach to ensure proper reduction and compression. Fractures of the scaphoid waist can be approached either by a volar or a dorsal approach. Kirschner wire fixation is limited to proximal pole fractures that are too small to accommodate the trailing head of a compression screw.
REFERENCES: Retting ME, Raskin KB: Retrograde compression screw fixation of acute proximal pole fractures. J Hand Surg Am 1999;24:1206-1210.
Filan SK, Herbert TJ: Herbert screw fixation of scaphoid fractures. J Bone Joint Surg Br 1996;78:519-529.

Question 57:

Options:

Abscess
Ganglion cyst
Nerve sheath tumor
Lymphoma
Metastatic cancer

Correct Answer: Ganglion cyst

Explanation:

Question 58:

Options:

Guillotine transtibial amputation
Standard transtibial amputation with a posterior myocutaneous flap and immediate prosthetic limb fitting
Culture-specific antibiotic therapy, open wound management, and metabolic/nutritional therapy
Culture-specific antibiotic therapy and Syme ankle disarticulation
Two-stage Syme ankle disarticulation

Correct Answer: Culture-specific antibiotic therapy, open wound management, and metabolic/nutritional therapy

Explanation:

Question 59:

Options:

Cut more proximal tibia.
Cut more distal femur.
Cut both the proximal tibia and distal femur.
Decrease the size of the femoral component.
Decrease the tibial polyethylene insert thickness.

Correct Answer: Decrease the size of the femoral component.

Explanation:

Question 60:

A 2-year-old boy has complete absence of the sacrum and lower lumbar spine. What is the most likely long-term outcome if no spinal pelvic stabilization is performed?

Options:

Progressive paralysis
Neck extension contracture
Inability to sit without using the hands for support
Progressive hip dislocation
Sexual dysfunction

Correct Answer: Inability to sit without using the hands for support

Explanation:

DISCUSSION: Without stabilization, progressive kyphosis will develop between the spine and pelvis. The kyphosis progresses to the point that the child must use his or her hands to support the trunk, and therefore is unable to use his or her hands for other activities. Neck extension contracture does not usually develop. Neurologic deficit, including sexual dysfunction, is generally present at birth and static.
REFERENCES: Tachdjian MO: The spine: Congenital absence of the sacrum and lumbosacral vertebrae (lumbosacral agenesis), in Wickland EH Jr (ed): Pediatric Orthopaedics, ed 2. Philadelphia, PA, WB Saunders, 1990, vol 3, p 2228.
Renshaw TS: Sacral agenesis: A classification and review of twenty-three cases. J Bone Joint Surg Am 1978;60:373-383.

Question 61:

Which of the following is considered the most accurate test to determine the amount of limb-length discrepancy in a patient with a knee flexion contracture of 35°?

Options:

Standing block test
Standing AP radiograph of the pelvis with blocks under the foot of the short leg
CT scanogram
Scanogram
Measurement from the anterior superior iliac spine to the medial malleolus

Correct Answer: CT scanogram

Explanation:

Question 62:

A 10-year-old boy who plays baseball reports acute pain after throwing a softball from the outfield to second base. A radiograph is shown in Figure 26. Management should consist of

Options:

observation during healing of the fracture, followed by bone marrow or corticosteroid injection.
biopsy and appropriate chemotherapy.
curettage and bone grafting.
high-dose systemic corticosteroids.
pulsed electromagnetic fields.

Correct Answer: observation during healing of the fracture, followed by bone marrow or corticosteroid injection.

Explanation:

Question 63:

Use of titanium elastic nailing for treatment of pediatric femur fractures is associated with a higher complication rate among

Options:

patients younger than age 6.5.
patients who bear weight immediately after surgery.
patients weighing more than 50 kg (110 pounds).
patients with grade 1 open transverse midshaft fractures.

Correct Answer: patients weighing more than 50 kg (110 pounds).

Explanation:

Question 64:

The histology of the lesion is shown in Figure 101d. What is the most likely complication after treatment of this lesion?

Options:

Arthrofibrosis
Local recurrence
Chondrolysis
Disseminated infection
Metastasis

Correct Answer: Local recurrence

Explanation:

DISCUSSION FOR QUESTIONS 101 THROUGH 103:
The MRI scans show a well-circumscribed inhomogenous mass at the anterior ankle joint consistent with a diagnosis of pigmented villonodular synovitis (PVNS), not an anatomic variant. An inflammatory mass,such as the pannus of rheumatoid arthritis, would reveal moderate signal intensity with relatively uniform signal throughout. The mass is well encapsulated, respecting tissue boundaries and not showing invasive characteristics as malignancies would. The arthroscopic image is also consistent with the reddish-brown frond-like tissue of PVNS. PVNS of the ankle can be treated arthroscopically. If this mode of treatment is chosen, a tissue sample should be sent to pathology for microscopic analysis; débridement should be performed on the remaining tissue. Removal of the instrumentation without débridement will not provide treatment and will result in disease progression. Tourniquet placement does not provide therapeutic benefit.
Brachytherapy has not been described for the treatment of PVNS of the ankle. The histologic image shows multiple multinucleated giant cells, hemosiderin, and very few mitotic figures – consistent with a diagnosis of PVNS. A common complication of PVNS treatment is local recurrence. Arthrofibrosis and chondrolysis are not seen with proper surgical care of these patients. Because this is not an infectious lesion, disseminated infection after treatment is highly unlikely. PVNS rarely metastasizes.
RESPONSES FOR QUESTIONS 104 THROUGH 106
Toe is fused too straight (plantar flexed)
Toe is fused in too much valgus
Toe is fused in too much dorsiflexion
There is a nonunion of the fusion
Excessive shortening of the first metatarsal during preparation for fusion What is the most likely diagnosis for each patient?

Question 65:

Options:

Revision total knee arthroplasty with placement of a hinge constrained device
Patellar tendon repair with nonabsorbable suture and patellar resurfacing
Hinged knee brace with drop lock design to restore stability during ambulation
Extensor mechanism reconstruction using synthetic mesh or allograft

Correct Answer: Extensor mechanism reconstruction using synthetic mesh or allograft

Explanation:

Question 66:

A 39-year-old man presents with back pain radiating to the left lower extremity for the past 6 weeks. Magnetic resonance images of the pathology are

Options:

Pain/parasthesias near the medial malleolus due to impingement of L4 nerve root
Pain/parasthesias near the medial malleolus due to impingement of L3 nerve root
Pain/parasthesias near the medial epicondyle of femur due to impingement of L4 nerve root
Pain/parasthesias near the medial epicondyle of femur due to impingement of L3 nerve root
Intermittent claudication due to impingement on segmental vessel

Correct Answer: Intermittent claudication due to impingement on segmental vessel

Explanation:

Question 67:

Options:

Add double metal uprights and a leather corset.
Add a supracondylar suspension to the soft suspension.
Add supracondylar and suprapatellar suspensions to the socket design.
Replace the socket insert with a silicone suction socket with locking bolt suspension.
Replace the prosthetic socket with a negative pressure vacuum system.

Correct Answer: Add double metal uprights and a leather corset.

Explanation:

Question 68:

Options:

Early passive range-of-motion in a hinged elbow brace
Application of a static spanning external fixator for 6 weeks
Radial head excision, coronoid excision, and repair of the lateral ulnar collateral ligament and medial collateral as needed
Radial head excision, open reduction internal fixation of the coronoid, and repair of the lateral ulnar collateral ligament and medial collateral as needed
Radial head replacement, open reduction internal fixation of the coronoid, and repair of the lateral ulnar collateral ligament and medial collateral as needed

Correct Answer: Early passive range-of-motion in a hinged elbow brace

Explanation:

Question 69:

Options:

Total contact orthotic
UCBL orthotic
Molded articulated ankle-foot orthosis
Molded ankle gauntlet (Arizona brace)
Lateral heel flare

Correct Answer: Molded ankle gauntlet (Arizona brace)

Explanation:

Question 70:

Which of the following is associated with the use of large femoral heads in total hip arthroplasty?

Options:

Increased risk of total hip dislocation
Decreased range of motion
Fewer options for femoral head bearing material
Acceptable wear with modern bearing surfaces
Increased component impingement

Correct Answer: Acceptable wear with modern bearing surfaces

Explanation:

Question 71:

Options:

Knee aspiration for culture
CT of the knee to assess implant rotation
Indium-111 leukocyte/technetium-99m sulfur colloid scan of the knee
Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) laboratory studies

Correct Answer: Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) laboratory studies

Explanation:

Question 72:

Avascular necrosis

Options:

Slipped epiphysis
This patient has a subtle grade 1 slipped capital femoral epiphysis. He is a male Risser 0 and is overweight. He has decreased internal rotation of the involved hip in flexion. The plain pelvis radiograph shows slightly less epiphyseal height on the left side, slight posterior metaphyseal overlap, and increased irregularity of the physis. MRI confirms a lucent plane in the physis and surrounding edema. A plain film (Slide 3) confirms the diagnosis. In situ fixation was performed on this patient.

Correct Answer: Slipped epiphysis

Explanation:

Slide
A 9-year-old girl sustains an injury (Slide) as a result of a fall. What is her risk of avascular necrosis:

Question 73:

Figure 10 shows the radiograph of an 18-year-old woman who sustained a spinal cord injury in a motor vehicle accident. Based on the radiographic findings, her injury is best described as

Options:

distractive extension.
compressive extension.
lateral flexion.
distractive flexion.
compressive flexion.

Correct Answer: distractive flexion.

Explanation:

Question 74:

03 Which of the following findings is one of the diagnostic criteria for diffuse idiopathic skeletal hyperostosis?

Options:

Flowing ossification along the anterolateral aspect of at least four contiguous vertebrae
Disk space collapse in the involved vertebral segments
Marginal syndesmophytes over four contiguous vertebrae
Sacroiliac erosion or sclerosis
Facet joint ankylosis Question 64.03

Correct Answer: Flowing ossification along the anterolateral aspect of at least four contiguous vertebrae

Explanation:

Question 75:

Why is tendon considered an anisotropic material?

Options:

Young’s modulus is greater than that of bone.
Young’s modulus is greater than that of ligament.
Mechanical properties change with preconditioning.
Intrinsic mechanical properties vary depending on the direction of loading.
Intrinsic mechanical properties vary depending on the rate of loading.

Correct Answer: Intrinsic mechanical properties vary depending on the direction of loading.

Explanation:

DISCUSSION: Anisotropic materials have mechanical properties that vary based on the direction of loading. The relative values of Young’s modulus for tendon, ligament, and bone are not relevant to isotropy. The mechanical properties of tendon do change with preconditioning, but this change is related to viscoelasticity. The intrinsic mechanical properties of tendon do vary with the rate of loading, but this variance is related to viscoelasticity.
REFERENCES: Buckwalter JA, Einhorn TA, Simon SR (eds): Orthopaedic Basic Science: Biology and Biomechanics of the Musculoskeletal System, ed 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000, pp 134-180.
Lu L, Kaufman KR, Yaszemski MJ: Biomechanics, in Einhorn TA, O’Keefe RJ,
Buckwalter JA (eds): Orthopaedic Basic Science: Foundations of Clinical Practice, ed 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2006, in press.

Question 76:

Options:

Modern cement technique
Porous-coated stem
Nonporous press-fit stem
Hydroxyapatite-coated stem
Cerclage wire fixation

Correct Answer: Modern cement technique

Explanation:

Question 77:

Options:

Ask the nurse to call the medical director
Ask the surgeon to revisit the surgical safety checklist
Assume the booking form was incorrect and proceed with the operation
Leave the operating room to ask a family member
Read the last clinical note for clarification

Correct Answer: Ask the nurse to call the medical director

Explanation:

Question 78:

Pharmacoprophylaxis should be avoided in favor of a pneumatic compression device for a patient with

Options:

protein C deficiency.
protein S deficiency.
factor V Leiden mutation.
factor VIII deficiency.

Correct Answer: factor VIII deficiency.

Explanation:

Question 79:

Options:

Bracing
Posterior spinal fusion of only the right thoracic curve
Posterior spinal fusion from T2-L4
Vertebral body stapling to halt progression of the curve
Anterior and posterior spinal fusion

Correct Answer: Posterior spinal fusion of only the right thoracic curve

Explanation:

DISCUSSION: The patient has typical adolescent idiopathic scoliosis with a right thoracic curve. This represents a Lenke-IB curve pattern; therefore, only treatment of the thoracic curve is required. The proximal thoracic and thoracolumbar curves are very flexible. The patient is Risser 1 and has just started her menstrual cycles; therefore, she is at significant risk for further curve progression. Bracing is not appropriate for a curve of this magnitude and will not halt the progression of this curve, nor will vertebral body stapling stop this curve. Vertebral body stapling is sometimes useful in small thoracic curves of less than 35 degrees and skeletally immature patients. Anterior and
14 • American Academy of Orthopaedic Surgeons
posterior spinal fusion is not required because the patient has no other risk factors, such as neurofibromatosis nor is she at risk for crankshaft. Anterior fusion is an option, but it is not listed.
REFERENCES: Lenke LG, Betz RR, Harmes J, et al: Adolescent idiopathic scoliosis: Anew classification to determine extent of spinal arthrodesis. J Bone Joint Surg Am 2001;83:1169-1181.
Lenke LG, Betz RR, Haher TR, et al: Multisurgeon assessment of surgical decision making in adolescent idiopathic scoliosis: Curve classification, operative approach, and fusion levels. Spine 2001;26:2347- 2353.

Question 80:

What is the most common problem seen following epiphysiodesis for limb-length discrepancy?

Options:

Fracture through the site of the physeal resection
Direct neurovascular injury
Incomplete growth arrest from inadequate physeal excision
Persistent discrepancy from an error in the timing of the surgery
Cartilaginous injury because of inadvertent joint penetration

Correct Answer: Persistent discrepancy from an error in the timing of the surgery

Explanation:

Question 81:

Options:

No treatment is indicated at this time
Figure of eight brace
Resection arthroplasty of the sternoclavicular joint
Sternoclavicular and costoclavicular ligament reconstruction
Sternoclavicular arthrodesis

Correct Answer: No treatment is indicated at this time

Explanation:

Question 82:

Options:

Hemiarthroplasty
Total shoulder arthroplasty
Reverse total shoulder arthroplasty
Arthroscopic debridement
Glenoid osteotomy and interposition arthroplasty

Correct Answer: Total shoulder arthroplasty

Explanation:

Question 83:

Options:

Referral to a pain clinic for epidural injections
Activity modification and anti-inflammatory medications
Urgent hospital admission followed by hemilaminotomy and diskectomy
Hemilaminotomy and diskectomy scheduled as an elective procedure
Posterior laminectomy and fusion

Correct Answer: Referral to a pain clinic for epidural injections

Explanation:

The patient has an L5-S1 disk herniation, which has a favorable prognosis without surgical intervention. Most acute lumbar disk herniations resolve with nonsurgical management. The most appropriate course of initial treatment should be analgesics and activity modification, followed by rehabilitation as the symptoms allow. Although the MRI scan indicates a large disk herniation, he has no symptoms or signs that would warrant urgent surgical decompression. Planned elective diskectomy should be considered only if nonsurgical management fails to provide relief. Epidural injections could be considered if the initial course of treatment fails to give the patient significant relief. Posterior laminectomy and fusion is not indicated without the presence of instability.
(SBQ12SP.9) A 62-year-old male underwent posterior spinal instrumented fusion for degenerative lumbar spondylolithesis one year ago. He presents to office complaining of persistent lower back pain. The pain initially improved but over the last 6 months he has had recurring pain at the site of the surgery primarily with activity. He denies back pain at rest or night pain. Physical examination reveals a well healed wound and no physical abnormalities. He has no tenderness to palpation to the thoracic or lumbar spine. He has no neurological deficits. His laboratory results show an erythrocyte sedimentation rate (ESR) = 8 mm/h and C-reactive protein (CRP) = 3 mg/L at the last visit which are both within normal limits. Figure A shows a series of radiographs from his pre-operative, 3 month post-operative and 1 year post-operative clinic visits, respectively. Which of the following investigations would best confirm the suspected underlying diagnosis?
Review
Topic
MRI of lumbar spine
Repeat ESR/CRP and whole body bone scan
CT of lumbar spine
Dynamic flexion/extension plain film radiographs
Dynamic lateral bending plain film radiographs
This patient has clinical and radiographic features of failed spinal arthrodesis. CT scan have been shown to be the most relable method for assessing spinal fusion postoperatively.
Reported rates of nonunion following posterior spinal fusion range from 0-70%. Rates are variable due to the various operative techniques, underlying diagnoses as well as asymptomatic patients. Non-union may lead to changes in alignment, spinal instability and potential neurological injury. Static radiographs have long been used as a practical method of fusion assessment, but these tend to significantly overestimate the presence of a solid fusion. Lack of movement at a fused segment, on dynamic views, does not confirm fusion. CT offers excellent bony resolution and are less affected by metal artifact compared to MRI.
Patel et al. showed that tobacco use, malnutrition, oral anti-inflammatory use, multilevel fusion, prior spine surgery, and sagittal imbalance are all risk factors for spinal nonunion.
Mok et al. looked at erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels after spinal surgery and compared their usefulness as predictors of infectious complications in the early postoperative period. They found that CRP is more applicable, predictable, and responsive in the early postoperative period compared with ESR. Using a second rise or failure to decrease as expected for CRP is sensitive for infection.
Shelby et al. reviewed the radiological assessment of spinal fusion. They comment that fine-cut imaging, multiplanar reconstruction, and metal artifact reduction have increased the ability to assess fusion on CT.
Figure A shows a series of lateral radiographs of the lumbar spine with posterior spinal instrumentation. Illustration A shows a lateral CT scan image of multi-level pseudoarthrosis after posterior spinal instrumented fusion. Illustration B shows an
intra-operative
view
of
spinal
pseudoarthrosis
(white
arrow).
Incorrect
(SBQ12SP.19) A 41-year-old male presents with acute onset of low back pain that started when he was trying to lift a heavy box while helping his brother move apartments two days ago. The pain has been severe enough to cause him to miss work yesterday. He has no neurologic deficits. What are the chances he will return to work within 6 weeks?
Review Topic
1 80 to 90%
2 70 to 80%
3 60 to 70%
4 50 to 60%
5 40 to 50%
Most adults (up to 80%) will experience an episode of low back pain in their lifetime. In those whose pain is severe enough to cause them to miss work, 60 to 70% will return by 6 weeks, and 80 to 90% will return by 12 weeks.
Low back pain is common in adults. Most patients experience resolution of symptoms quickly and have no lasting loss of function. However, 5 to 10% develop chronic pain. Recurrence of pain is common, and is part of the natural history, occurring in 20 to 72% of patients. After 12 weeks, return to work rates are slow.
Shen et al. review the nonoperative management of acute and chronic low back pain. The authors note that none of the available interventions has been proven by high quality large randomized controlled trials. The authors believe that low dose oral
steroids are safe in the short term and that injection therapy should not be used without a reasonable presumptive diagnosis.
Madigan et al. review the management of lumbar degenerative disease. The authors emphasize that the majority of patients improve within 6 weeks with or without treatment. For patients that do not, the authors do not recommend epidural injection, as there are no good studies to support their use in the treatment of discogenic back pain. When surgical treatment is indicated they state that arthrodesis is the gold standard, although the long term results of total disk arthroplasty are being elucidated.
Illustration A shows a table of available non-operative treatment modalities for back pain. Illustration B shows a list of possible diagnoses associated with acute low back pain, with those associated with neurogenic pain italicized. Illustration C shows a list of 'red flag' symptoms indicating serious/emergent causes of low back pain.
Incorrect
2:
Longer
to than
90%

Question 84:

Which of the following factors is associated with improved outcomes following surgery for hip fractures?

Options:

Immediate surgical intervention
Early discharge to a skilled nursing facility
Choosing spinal versus general anesthesia for surgery
Choosing total hip arthroplasty instead of hemiarthroplasty for a displaced femoral neck fracture
Correction of metabolic abnormalities prior to surgical intervention

Correct Answer: Correction of metabolic abnormalities prior to surgical intervention

Explanation:

Question 85:

Prescribing touch (10 to 15 kg) weight-bearing would be most appropriate in the following scenario?

Options:

Acute grade II anterior talofibular ligament ankle sprain
Partial lateral menisectomy for incomplete radial tear
Open reduction internal fixation for comminuted calcaneus fracture
Cemented hemiarthroplasty for displaced femoral neck fracture
Open reduction internal fixation for transtectal transverse posterior wall fracture

Correct Answer: Acute grade II anterior talofibular ligament ankle sprain

Explanation:

Question 86:

Options:

Eccentric
Concentric
Isometric
Isokinetic

Correct Answer: Eccentric

Explanation:

Question 87:

Resuscitation of a trauma patient who has been in hypovolemic shock is complete when which of the following has occurred?

Options:

The mean arterial blood pressure is above 90 mm Hg.
The pulse pressure has normalized.
Urine output is greater than 0.5 to 1 mL/kg/h.
Oxygen delivery has been maximized.
Aerobic metabolism has been restored in all tissue beds.

Correct Answer: Aerobic metabolism has been restored in all tissue beds.

Explanation:

DISCUSSION: Shock can be defined as inadequate tissue perfusion. Resuscitation or the resolution of shock is defined as when oxygen debt has been repaid, tissue acidosis is eliminated, and aerobic metabolism has been restored in all tissue beds. The end points for resuscitation are not clearly defined, but occult shock can still be present in the setting of normal vital signs and normal urine output due to selective perfusion of organ systems.
REFERENCES: Tisherman SA, Barie P, Bokhari F, et al: Clinical practice guideline: End point of resuscitation. J Trauma 2004;57:898-912.
Moore FA, McKinley BA, Moore EE, et al: Inflammation and the Host Response to Injury, a large-scale collaborative project: Patient-oriented research core--standard operating procedures for clinical care. III. Guidelines for shock resuscitation. J Trauma 2006;61:82-89.
Englehart MS, Schreiber MA: Measurement of acid-base resuscitation end points: Lactate, base deficit, bicarbonate or what? Curr Opin Crit Care 2006;12:569-574.

Question 88:

What antithrombotic agent is a selective factor I0a inhibitor? Review Topic

Options:

Warfarin
Low-molecular-weight heparin
Rivaroxaban
Aspirin

Correct Answer: Rivaroxaban

Explanation:

Question 89:

Options:

Continue physical therapy
Latissimus dorsi transfer
Arthroscopic rotator cuff repair
Pectoralis major transfer
Reverse total shoulder arthroplasty

Correct Answer: Pectoralis major transfer

Explanation:

Question 90:

Options:

significantly reduced wear and greater mid-term implant survival.
increased wear and increased fracture rate of the liner.
decreased mid-term implant survival when compared with UHMWPE.
reduced wear, but increased osteolysis. XLPE was developed to address the problem of wear and osteolysis associated with conventional UHMWPE-bearing surfaces. Data have shown, with randomized controlled trials, that XLPE liners have significantly reduced wear and are associated with greater implant survival at 10 years compared with UHMWPE-bearing surfaces.

Correct Answer: increased wear and increased fracture rate of the liner.

Explanation:

Question 91:

Survival rates for children with soft-tissue sarcoma other than rhabdomyosarcoma are best correlated with

Options:

size of the tumor.
histologic grade.
histologic subtype.
use of adjuvant chemotherapy.
age of the patient.

Correct Answer: histologic grade.

Explanation:

Question 92:

A 69-year-old female sustains the injuries seen in Figures A and

Options:

This injury is best classified as which of the following?
Schatzker type I tibial plateau fracture
Schatzker type III tibial plateau fracture
Schatzker type IV tibial plateau fracture
Schatzker type V tibial plateau fracture
Schatzker type VI tibial plateau fracture

Correct Answer: Schatzker type I tibial plateau fracture

Explanation:

Question 93:

271 Which of the following factors has been shown to contribute to poor results after anatomic reduction of posterior wall acetabulum fractures?

Options:

Marginal articular impaction
Involvement of the weight-bearing dome
Delay in reduction of hip dislocation of greater than 12 hours
Size of wall fragment
Patient age of less than 40 years
back answer Question 03.271

Correct Answer: Delay in reduction of hip dislocation of greater than 12 hours

Explanation:

Question 94:

Compared to similar patients who do not donate autologous blood, patients with normal baseline hemoglobin who donate autologous blood prior to undergoing primary total hip arthroplasty are likely to

Options:

receive an allogeneic transfusion.
experience cardiac complications perioperatively.
have a greater likelihood of receiving a transfusion perioperatively.
have a higher hemoglobin at the time of discharge.
have deep venous thrombosis postoperatively.

Correct Answer: have a greater likelihood of receiving a transfusion perioperatively.

Explanation:

Question 95:

What adaptations occur in the dominant shoulder of throwers compared to their nondominant shoulder? Review Topic

Options:

Humeral anteversion with a normal total arc of motion
Tight posterior capsule with a normal total arc of motion
Lengthening of the anterior capsule with a decreased total arc of motion
Increased external rotation with a decreased total arc of motion
Decreased internal rotation with an increased total arc of motion

Correct Answer: Tight posterior capsule with a normal total arc of motion

Explanation:

Question 96:

When compared with the normal anterior cruciate ligament (ACL), placement of an anterior cruciate ligament graft in the over-the-top position on the femoral side has what effect on its function?

Options:

Lax in flexion and tight in extension
Lax in flexion and lax in extension
Tight in flexion and lax in extension
Tight in flexion and tight in extension
Remains isometric

Correct Answer: Lax in flexion and tight in extension

Explanation:

Question 97:

Options:

Musculocutaneous nerve
Posterior humeral circumflex artery
Axillary nerve
Cephalic vein
Anterior humeral circumflex artery

Correct Answer: Musculocutaneous nerve

Explanation:

Question 98:

The use of multiagent adjuvant chemotherapy is associated with a clear survival benefit in which of the following diseases?

Options:

Renal carcinoma
Osteosarcoma
Dedifferentiated chondrosarcoma
Adult soft-tissue sarcoma
Melanoma

Correct Answer: Osteosarcoma

Explanation:

Question 99:

Options:

Technetium Tc 99m bone scan
Intravenous antibiotics
Oral antibiotics
CT of the hips
Aspiration of the left hip

Correct Answer: Aspiration of the left hip

Explanation:

DISCUSSION: Examination reveals an irritable hip, creating a differential diagnosis of transient synovitis versus pyogenic hip arthritis. Kocher and associates described four criteria to help predict the presence of infection: inability to bear weight, fever, ESR of more than 40 mm/h, and a peripheral WBC count of more than 12,000/mm
P
3
P
. This patient meets three of the four criteria, with a positive predictive value of 73% to 93% for joint infection. Therefore, aspiration of the hip is warranted, with a high likelihood that emergent hip arthrotomy will be indicated. Ideally, intravenous antibiotics should be administered after culture material has been obtained from needle aspiration of the hip. An urgent bone scan is better indicated as a screening test for sacroiliitis or diskitis. If the arthrocentesis proves negative, CT or MRI of the pelvis may be indicated to rule out a pelvic or psoas abscess.
REFERENCES: Del Beccaro MA, Champoux AN, Bockers T, et al: Septic arthritis versus transient synovitis of the hip: The value of screening laboratory tests. Ann Emerg Med 1992;21:1418-1422.
Kocher MS, Mandiga R, Zurakowski D, et al: Validation of a clinical prediction rule for the differentiation between septic arthritis and transient synovitis of the hip in children. J Bone Joint Surg Am 2004;86:1629-1635.
Kocher MS, Zurakowski D, Kasser JR: Differentiating between septic arthritis and transient synovitis of the hip in children: An evidence-based clinical prediction algorithm. J Bone Joint Surg Am 1999;81:1662-1670.

Question 100:

- A 14-year-old girl has idiopathic scoliosis with a 52-degree right thoracic curve and a 36-degree left lumbar curve. The rotation of the apical vertebra appears greater in the thoracic curve. A sagittal view radiograph shows the spine to be virtually straight. The iliac apophyses are Risser 2. Treatment should consist of

Options:

Anterior fusion of the lumbar curve
Anterior and posterior fusion of the thoracic curve
Posterior fusion of the thoracic curve
Posterior fusion of the thoracic and lumbar curves
Application of a brace until the iliac apophyses are Risser 4 or 5, followed by surgical correction

Correct Answer: Posterior fusion of the thoracic curve

Orthopedic Surgery Board Review MCQs: Arthroplasty, Ligament & Spine | Part 149

Orthopedic Board Review MCQs: Ankle, Deformity, Fracture & Scoliosis | Part 113

Key Takeaway

About This Board Review Set

How to Use the Interactive Quiz

Topics Covered in Part 113

Sample Questions from This Set

Why Active MCQ Practice Works

Chapter Index