Spine, Arthroplasty & Trauma Orthopedic MCQs - Part 187

About This Board Review Set

This is Part 187 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 187

This module focuses heavily on: Arthroplasty, Fracture, Knee, Nerve, Spine.

Sample Questions from This Set

Sample Question 1: Which of the following is a contraindication to laminoplasty in a patient with cervical spondylotic myelopathy? Review Topic...

Sample Question 2: A 65-year-old woman has nausea, vomiting, and abdominal distention after undergoing total knee arthroplasty 48 hours ago. An abdominal radiograph is shown in Figure 14. Associated risk factors for this disorder include...

Sample Question 3: To prevent injury to the posterior interosseous nerve during the approach for reduction and fixation of a fracture of the radial head, anterior retraction should be performed with the forearm...

Sample Question 4: From which artery does the princeps pollicis artery branch?...

Sample Question 5: Vertebral fractures are common in the thoracolumbar spine. What is the most important factor that determines the strength of the cancellous bone in the vertebral body?...

Why Active MCQ Practice Works

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

Which of the following is a contraindication to laminoplasty in a patient with cervical spondylotic myelopathy? Review Topic

Explanation

Laminoplasty or any posterior decompressive procedure is contraindicated in patients with cervical spondylotic myelopathy and cervical kyphosis. The residual kyphotic posture of the cervical spine results in persistent spinal cord compression. The other choices are not contraindications for laminoplasty. Concomitant cervical radiculopathy can be addressed at the time of laminoplasty with a keyhole foraminotomy.

Question 2

A 65-year-old woman has nausea, vomiting, and abdominal distention after undergoing total knee arthroplasty 48 hours ago. An abdominal radiograph is shown in Figure 14. Associated risk factors for this disorder include

Explanation

DISCUSSION: The prevalence of postoperative ileus associated with total joint arthroplasty has been reported to be as high as 3%. Metabolic abnormalities such as hypokalemia are believed to contribute to the onset of ileus and Ogilvie’s syndrome (acute pseudo-obstruction of the colon). Prolonged bed rest also has been associated with the development of ileus and Ogilvie’s syndrome. Untreated Ogilvie’s syndrome can result in cecal perforation. Ileus usually is not accompanied by mechanical obstruction. Antibiotic administration and the type of anesthesia used have not been correlated with development of ileus. Administration of warfarin has been associated with elevated prothrombin time/partial thromboplastin time and international normalized ratio levels when ileus is managed with a nasogastric tube and suction. Metabolic imbalances must be corrected to reverse the ileus process.
REFERENCES: Iorio R, Healy WL, Appleby D: The association of excessive warfarin anticoagulation and postoperative ileus after total joint replacement surgery. J Arthroplasty 2000;15:220-223.
Clarke HD, Berry DJ, Larson DR: Acute pseudo-obstruction of the colon as a postoperative complication of hip arthroplasty. J Bone Joint Surg Am 1997;79:1642-1647.

Question 3

To prevent injury to the posterior interosseous nerve during the approach for reduction and fixation of a fracture of the radial head, anterior retraction should be performed with the forearm

Explanation

Position of the patient-Place supine on the operating table, with the affected arm positioned over the chest. Pronate the forearm.
Deep surgical dissection-Fully pronate the forearm to move the posterior interosseous nerve away from the operative field. Incise the capsule of the elbow joint longitudinally to reveal the underlying capitulum, the radial head, and the annular ligament. Do not incise the capsule too far anteriorly; the radial nerve runs over the front of the anterolateral portion of the elbow capsule. Do not continue their dissection below the annular ligament or retract vigorously, distally, or anteriorly, because the posterior interosseous nerve lies within the substance of the supinator muscle and is vunerable to injury.
Dangers: Nerves-The posterior interosseous nerve is in no danger as long as the dissection remains proximal to the annular ligament. Pronation of the forearm keeps the nerve as far from the operative field as it possible can be. To ensure the safety of the nerve, take great care to place the retractors directly on the bone and be careful in their placement. Because the posterior interosseous nerve actually may touch the bone of the radial neck, directly opposite the bicipital tuberosity, placing retractors behind it poses a risk.

Question 4

From which artery does the princeps pollicis artery branch?

Explanation

DISCUSSION
The princeps pollicis artery can be located on the palmar aspect of the adductor pollicis and emerges into the subcutaneous tissue at the thumb metacarpophalangeal flexion crease. It branches from the radial artery just distal to the location of the deep palmar arch.
RECOMMENDED READINGS
Coleman SS, Anson B: Arterial patterns in the hand based on a study of 650 specimens. Surg Gynec Obstet 1961;4:409-424.
Ames EL, Bissonnette M, Acland R, Lister G, Firrell J. Arterial anatomy of the thumb. 78 J Hand Surg Br. 1993 Aug;18(4):427-36. PubMed PMID: 8409651. View Abstract at PubMed

Question 5

Vertebral fractures are common in the thoracolumbar spine. What is the most important factor that determines the strength of the cancellous bone in the vertebral body?

Explanation

DISCUSSION: Cancellous bone strength and stiffness are determined primarily by the apparent density (the amount of bone per unit volume). Strength varies approximately as the square of the density, and stiffness as the cube of the density; therefore, these are very strong relationships. Cancellous bone strength also depends on the mineral content, the rate of loading (it is viscoelastic), the anatomic level, and the trabecular number (an histomorphometry term), but all to a markedly lesser extent than density.
REFERENCES: Carter DR, Hayes WC: The compressive behavior of bone as a two-phase porous structure. J Bone Joint Surg Am 1977;59:954-962.
Keaveny TM: Strength of trabecular bone, in Cowin SC (ed): Bone Mechanics Handbook. Boca Raton, FL, CRC Press, 2001, pp 16-1-16-8.

Question 6

What joint always remains uninvolved in all stages of scapholunate advanced collapse (SLAC) deformity of the wrist?

Explanation

DISCUSSION: The development of arthritis in SLAC wrist follows a consistent pattern. Beginning at the radial styloid to the scaphoid articulation, it progresses through the entire radioscaphoid joint and the midcarpal joint. In all stages, the radiolunate joint is spared, which is the basis for a scaphoid excision and four-corner fusion performed as a motion-sparing procedure for treatment of this condition.
REFERENCES: Wyrick JD: Proximal row carpectomy and intercarpal arthrodesis for the management of arthritis. J Am Acad Orthop Surg 2003;11:277-281.
Watson HK, Ballett FL: The SLAC wrist: Scapholunate advanced collapse pattern of degenerative arthritis. J Hand Surg Am 1984;9:358-365.
Watson HK, Ryu J: Evolution of arthritis of the wrist. Clin Orthop 1986;202:57-67.

Question 7

A 55-year-old woman with type I diabetes mellitus has a chronic ulcer over the dorsum of her right foot and reports forefoot pain. Examination reveals 1- x 2-cm nondraining ulcer over the dorsum of the foot. The patient has 1-2+ pain with compression of the foot and ankle. She has a weakly palpable posterior tibial pulse and an absent dorsalis pedis pulse. There is no erythema, cellulitis, or drainage. Radiographs are normal. Which of the following diagnostic studies should be obtained?

Explanation

DISCUSSION: The presence of a dorsal ulcer in the presence of weak or absent pulses strongly suggests the possibility of arterial insufficiency. The best initial noninvasive study to assess for ischemia is the Doppler arterial study. A determination of the vascular status is of a greater priority than an assessment for infection or neuropathy because of the location and presentation of the ulcer. If ankle pressures are less than 45 mm Hg, there is a high risk that these lesions will not heal without revascularization.
REFERENCES: Wagner FW Jr: The dysvascular foot: A system for diagnosis and treatment. Foot Ankle 1981;2:64-122.
Apelqvist J, Castenfors J, Larson J, Stenstrom A, Agardh CD: Prognostic value of systolic ankle and toe blood pressure levels in outcome of diabetic foot ulcer. Diabetes Care 1989;12:373-378.

Question 8

Based on the radiographic findings shown in Figure 41, which of the following wrist ligaments is most likely disrupted?

Explanation

DISCUSSION: The radiograph shows a diastasis of the scapholunate interval, caused by certain failure of the scapholunate interosseous ligament. The lunotriquetral interosseous ligament stabilizes the lunotriquetral joint. The long radiolunate ligament originates in the volar radius and inserts in the lunate. The short radiolunate ligament originates on the ulnar margin of the radius and inserts on the ulnar margin of the lunate. The ulnolunate ligament originates at the ulnar styloid base and inserts on the volar aspect of the lunate.
REFERENCES: Linscheid RL, Dobyns JH, Beabout JW, et al: Traumatic instability of the wrist: Diagnosis, classification, and pathomechanics. J Bone Joint Surg Am 1972;54:1612-1632.
Mayfield JK, Johnson RP, Kilcoyne RK: Carpal dislocations: Pathomechanics and progressive perilunar instability. J Hand Surg Am 1980;5:226-241.
Berger RA: Ligament anatomy, in Cooney WP, Linscheid RL, Dobyns JH (eds): The Wrist, Diagnosis and Operative Management. St Louis, MO, Mosby, 1998, pp 73-105.

Question 9

-What is the etiology of this patient’s problem?

Explanation

DISCUSSION FOR QUESTIONS 78 THROUGH 80
Little leaguer’s shoulder is an overuse condition of the proximal humeral physis. Patients report diffuse pain that is worse with throwing. Factors that contribute to the condition include excessive throwing,improper throwing mechanics, and muscle-tendon imbalance. Radiographs usually show widening of the proximal humeral physis, and, in more severe cases, metaphyseal demineralization or fragmentation. Surgical fixation is not required for healing. Treatment involves rest until symptoms resolve, followed by initiation of an interval throwing program. Pitching coaches should evaluate throwing mechanics and maintain pitch counts. The dominant shoulders of throwing athletes undergo adaptive changes, resulting in increased external rotation and decreased internal rotation. These changes occur secondary to softtissue and bony adaptations, including increased humeral retroversion. Ischemia has been implicated as a potential cause of osteochondritis dissecans lesions. Rotator cuff tendonitis presents with anterolateral shoulder pain that is worse with activity. Pain is reproduced with resisted supraspinatus testing, and radiograph findings are typically normal.
Adolescent shoulder injuries are often caused by subtle, atraumatic instability most often sustained in sports with overhead movements, including baseball. These symptoms are more likely to occur in athletes with evidence of increased soft-tissue laxity.

Question 10

Figures A and B are axial and coronal MRI images of a 21-year-old male athlete. He injured his left leg during a hurdling race approximately 1 week ago. What would be the next best step in the management of this injury? Review Topic

Explanation

Figures A and B show an acute proximal hamstring tendon avulsion. The next best step in management would be open surgical repair of all tendons to their origin at the ischial tuberosity.
Athletes participating in sports that require sprinting, jumping, acceleration and deceleration are at increased risk of sustaining a proximal hamstring tendon avulsion. The greatest predictor of this injury is prior hamstring injury. Other risk factors include increasing age, high training demand, increased body mass index and tight hip flexor muscles. MRI is the gold standard imaging to identify these images. Open hamstring tendon repair is recommended in athletes when all of the hamstring tendons have avulsed off their origin or 2 tendons have avulsed and retracted more than 2 cm.
Cohen et al. wrote a JAAOS article on acute proximal hamstring rupture. They point out that testing the peroneal branch of the sciatic nerve function is important in the physical examination, as injury to this branch will cause weakness of the short head of the biceps femoris and may slow potential postoperative rehabilitation.
Lefevre et al. reviewed the return to sports after surgical repair of acute proximal hamstring ruptures. They performed a prospective observational study that included 34 patients. Patients returned to sports within a mean 5.7 ± 1.6 months, at the same level in 27 patients (79.4 %) and at a lower level in 7 patients (20.6 %). They conclude that surgical repair of acute proximal hamstring ruptures has the potential to significantly improve the functional prognosis of patients with these injuries.
Figures A and B shows a significant amount of swelling and hematoma around the hamstring tendon. The whole ischial tuberosity is denuded of tendon, which is consistent with a complete rupture. Illustration A shows a large posterior thigh ecchymosis commonly seen with this injury. The ecchymosis presents approximately 1 week following injury, which is know as latent ecchymosis. Illustration B shows a
schematic and intraoperative image of the open tendon repair of an acute injury.
Incorrect

Question 11

A 45-year-old man who sustains a medial subtalar dislocation while playing basketball undergoes immediate closed reduction. No fractures or osteochondral defects are noted on postreduction radiographs. The next most appropriate step in management should consist of

Explanation

DISCUSSION: Most subtalar dislocations can be easily reduced by closed methods. If no fractures or defects are seen on the postreduction radiographs, then the success rate with cast immobilization is good. Medial dislocations have a better prognosis than lateral dislocations. Late instability is rare; therefore, the duration of immobilization should not be excessive. Most subtalar dislocations result in some stiffening of the hindfoot, and painful degenerative arthrosis is the most common serious complication.
REFERENCE: Saltzman C, Marsh JL: Hindfoot dislocations: When are they not benign? J Am Acad Orthop Surg 1997;5:192-198.

Question 12

A 29-year-old man reports severe knee instability and popliteal pain. History reveals that he had polio of the left lower extremity as a child and has been brace-free his entire life. Examination reveals that he walks with 40° of knee hyperextension and has a fixed ankle equinus deformity of 30° . He has no active motors about the knee or ankle. Which of the following methods will provide knee stability and pain relief?

Explanation

DISCUSSION: The ankle equinus allows the patient to keep his weight-bearing line anterior to the axis of the hyperextended knee joint. With time, pain has developed because of continued stretching and now incompetence of the posterior capsule of the knee joint. Several soft-tissue and bony procedures have been designed to provide knee stability in this situation; however, the results have been either short-lived or inconsistent. Tenodeses, capsular plications, and bony blocks have had limited success and generally fail over time. Current orthotic technology makes soft-tissue release and orthotic control the most predictable option. To decrease the hyperextension moment on the knee joint, the ankle deformity also must be corrected. The most predictable method of achieving stability and diminished pain during walking is with soft-tissue release of the ankle and a knee-ankle-foot orthosis with a locked ankle and drop-lock knee joint.
REFERENCE: Michael JW: Lower limb orthoses, in Goldberg B, Hsu JD (eds): Atlas of Orthoses and Assistive Devices. St Louis, MO, Mosby, 1997, pp 209-224.

Question 13

A 17-year-old football player is tackled with an opposing player's helmet hitting him hard in the abdomen. He is knocked backwards and suffers a diaphyseal femur fracture. He denies any loss of consciousness. Vital signs reveal a heart rate of 118, mean arterial pressure (MAP) of 68, and a respiration rate of 32 per minute. A FAST ultrasound study shows trace free fluid in the perisplenic space. A CBC taken prior to bolus IV fluids reveals a hematocrit of 48%, and a blood gas shows a lactate level of 1.8 and a base excess of -2.0. Which of the follow statements regarding the patient's hemodynamic status is correct?

Explanation

Normal lactate levels or base excess indicate adequate tissue perfusion.
Hypovolemic shock leads to poor tissue perfusion due to inadequate flow or oxygenation. If a patient is in compensated shock (i.e. normal vital signs), there may be ongoing inadequate perfusion of some end-organs. Elevated lactate or a base deficit are markers of poor end-organ perfusion, thus when normalized indicate appropriate end-organ perfusion even if vital sign derangements persist.
Rossaint et al. wrote a comprehensive review article in 2006 in which they discuss principles of fluid management, coagulopathy, hypothermia and tissue oxygenation in hypovolemic shock. In addition to prolonged elevated lactate levels correlating to mortality, lactate levels (or base deficits) can be used to evaluate for compensated shock in the setting of normal hemodynamic status.
Illustration A shows the classification of hypovolemic shock. Note the percent of blood loss required for vital sign abnormalities.
Incorrect Answers:
setting of massive blood loss. The hematocrit only changes once the patient has physiologic or iatrogenic fluid shifts in response to the blood loss. Answer 3: Vital sign derangements indicate uncompensated shock, but do not directly measure tissue perfusion or end-organ damage Answer 5: Though uncommon, bleeding from isolated femur fractures can lead to Class II shock (blood loss 15-30%)

Question 14

As a diaphyseal fracture heals, peripheral callus forms about the shaft axis, creating a structure with a substantially larger diameter than the original diaphyseal shaft. What biomechanical properties does this callus impart to the healing fracture site?

Explanation

Callus formation is biomechanically benefecial because it increases the outer diameter of the bone, leading to an increase in stiffness, torsional strength, moment of inertia, and decreases resultant interfragmentary strain at the fracture site.
The biomechanical role of the peripheral callus is to provide initial stability to the fracture and to act as a scaffold for gradual mineralization. Because the bending stiffness of a structure is proportional to the 4th power of the diameter, a peripherally located callus provides substantial stability to the fracture, despite the relatively low stiffness and strength of callus. For example, doubling the diameter of the callus increases the resistance to bending by a factor of 16. As mineralization progresses, the bending stiffness and strength of the healed fracture eventually may be substantially greater than that of the original, intact bone.
Augat et al. review the mechanical and biological aspects of fracture healing. They report that increased diameter of periosteal callus formation benefits healing by enlarging the cross-sectional area of area of the bridging tissue and reducing interfragmentary motion. Patients with osteoporosis are known to have decreased callus mineralization and biomechanical properties.
Incorrect Answers:

Question 15

Figures 1 and 2 are the MRI scans of a 35-year-old right-hand dominant man who has right elbow pain after trying to lift a large television at home. An examination reveals ecchymosis, an abnormal hook test, and altered biceps muscle contour. What treatment is most likely to result in a satisfactory and predictable outcome?

Explanation

Figures 1 and 2 show a full thickness distal biceps tendon rupture with proximal retraction. Edema is seen along the course of the distal biceps tendon, and the axial cut demonstrates the absence of tendon at the radial tuberosity. The sagittal cut demonstrates the stump of the proximally retracted biceps tendon. The biceps muscle contour is abnormal in appearance, demonstrating the classic “popeye” deformity. Nonsurgical treatment options result in predictable loss of supination and elbow flexion strength that is not desirable. A local corticosteroid injection would not improve strength, and there is no evidence to support the use of a PRP injection.

Question 16

..One week after closed reduction of a primary anterior shoulder dislocation, a 25-year-old athlete should be counseled that

Explanation

CLINICAL SITUATION FOR QUESTIONS 36 THROUGH 39
A 65-year-old man experienced 6 years of worsening shoulder pain. Examination demonstrates stiffness and crepitus with range of motion, but full rotator cuff strength in all planes. Radiographs show advanced shoulder osteoarthritis, and an MRI scan ordered by the patient's primary care physician shows an intact rotator cuff.

Question 17

Figure 13 shows the radiographs of a 56-year-old woman who has pain and varus knee deformity after undergoing total knee arthroplasty 8 years ago. Aspiration and studies for infection are negative. During revision surgery, management of the tibial bone loss is best achieved by

Explanation

DISCUSSION: Massive bone loss encountered in revision total knee arthroplasty remains a significant challenge. Recent reports have shown high success rates using structural allograft to reconstruct massive bone defects. Custom and hinged prostheses in this setting are no longer favored. The defect shown is segmental and is too large to be filled with cement or iliac crest bone graft.
REFERENCES: Mow CS, Wiedel JD: Structural allografting in revision total knee arthroplasty. J Arthroplasty 1996;11:235-241.
Engh GA, Herzwurm PJ, Parks NL: Treatment of major defects of bone with bulk allografts and stemmed components during total knee arthroplasty. J Bone Joint Surg Am 1997;79:1030-1039.
Clatworthy MG, Ballance J, Brick GW, Chandler HP, Gross AE: The use of structural allograft for uncontained defects in revision total knee arthroplasty: A minimum five-year review. J Bone Joint Surg Am 2001;83:404-411.

Question 18

The spinal cord terminates as the conus medullaris at what vertebral level in adults? Review Topic 1 T12

Explanation

The spinal cord anatomy changes at the thoracolumbar junction. The spinal cord terminates as the conus medullaris at the lower portion of L1 in women and the pedicle of L1 in men.

Question 19

A football lineman who sustained a traumatic injury while blocking during a game now reports that his shoulder is slipping while pass blocking. Examination reveals no apprehension in abduction and external rotation; however, he reports pain with posterior translation of the shoulder. He has full strength in external rotation, internal rotation, and supraspinatus testing. What is the pathology most likely responsible for his symptoms? Review Topic

Explanation

Traumatic posterior instability is a common finding in football players, especially in the blocking positions as well as in the defensive linemen and linebackers. A traumatic blow to the outstretched arm results in posterior glenohumeral forces. Labral detachment at the glenoid rim is common. Patients report slipping or pain with posteriorly directed pressure. Rarely do these patients have true dislocations that require reduction; however, recurrent episodes of subluxation or pain are not uncommon. Posterior repair has been shown to be successful in the treatment of traumatic instability.

Question 20

Figures 1 through 3 demonstrate the radiographs obtained from a 25-year-old man who injured his right, by punching a wall 3 weeks earlier. He notes pain and deformity about the ulnar aspect of his hand. The best treatment option is

Explanation

EXPLANATION:
The initial radiographs reveal a fourth and fifth carpometacarpal (CMC) joint fracture dislocation. The injury is associated with a shear fracture of the dorsal rim of the hamate. Further assessment with CT might be helpful in fully evaluating the extent of injury. Extensor carpi ulnaris is a deforming force at the base of the fifth metacarpal. This unstable fracture dislocation could be treated with closed reduction and pinning if the patient presented within a few days of injury. However, because he presented in a delayed fashion (3 weeks after injury), open reduction with internal fixation was required (Figures 4 and 5). In the series by Zhang and associates, patients with fourth and fifth CMC fracture dislocations presenting in a delayed fashion and treated nonsurgically had suboptimal results. Therefore, closed reduction and casting are not appropriate. An arthrodesis and resection arthroplasty are salvage procedures considered for a painful arthritic joint and would less likely should not be considered for this acute injury.

Question 21

A 28-year-old woman who is training for the New York Marathon reports pain in the posteromedial aspect of her right ankle. Examination reveals tenderness just posterior to the medial malleolus. Radiographs are normal. An MRI scan is shown in Figure 3. What is the most likely diagnosis?

Explanation

DISCUSSION: Any of the above conditions is credible with a limited history. The MRI scan unequivocally shows the stress fracture in the distal tibia. Most tibial stress fractures can be managed with rest and immobilization.
REFERENCES: Boden BP, Osbahr DC: High risk stress fractures: Evaluation and treatment. J Am Acad Orthop Surg 2000;8:344-353.
Lee JK, Yao L: Stress fractures: MR imaging. Radiology 1988;169:217-220.

Question 22

Which of the following statements regarding conus medullaris syndrome is most accurate?

Explanation

DISCUSSION: Conus medullaris syndrome most frequently occurs as a result of trauma or with a disk herniation at L1, resulting in a lower motor neuron syndrome but with a poor prognosis for recovery of bowel and bladder dysfunction. The conus region, as the termination of the spinal cord, contains the motor cell bodies of the sacral roots. The syndrome is usually a sacral level neural injury; therefore, lower extremity weakness is uncommon.
REFERENCES: Haher TR, Felmly WT, O’Brien M: Thoracic and lumbar fractures: Diagnosis and management, in Bridwell KH, Dewald RL, Hammerberg KW, et al (eds): The Textbook of Spinal Surgery, ed 2. New York, NY, Lippincott Williams & Wilkins, 1977, pp 1773-1778.
Reitman CA (ed): Management of Thoracolumbar Fractures. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2004, pp 35-45.

Question 23

A complication unique to computer navigation of total knee arthroplasty (TKA) is

Explanation

CLINICAL SITUATION FOR QUESTIONS 111 THROUGH 113
Figure 111 is the anteroposterior radiograph of a 79-year-old woman with a presurgical diagnosis of osteonecrosis who sustained a periprosthetic tibia fracture following her total knee arthroplasty (TKA).

Question 24

A 69-year-old man reports pain over his bunion while wearing shoes and pain in the joint with push-off when barefoot. Nonsurgical management has failed to provide relief. Radiographs are shown in Figures 8a and 8b. What is the surgical procedure of choice?

Explanation

DISCUSSION: Arthrodesis is indicated for severe bunion and hallux valgus deformities, but particularly with extensive degenerative disease of the first metatarsophalangeal joint. The other bunionectomy procedures have different indications, none of which include symptomatic first metatarsophalangeal degenerative disease.
REFERENCES: Richardson EG (ed): Orthopaedic Knowledge Update: Foot and Ankle 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2004, pp 3-15.
Tourne Y, Saragaglia D, Zattara A, et al: Hallux valgus in the elderly: Metatarsophalangeal arthrodesis of the first ray. Foot Ankle Int 1997;18:195-198.

Question 25

Which of the following forms of nonsurgical management is considered best for acute low back pain without radiculopathy?

Explanation

DISCUSSION: Temporary bed rest (less than 4 days) with gradual resumption of activities can be efficacious. Epidural steroid injections may be indicated for acute low back pain with radiculopathy. Acupuncture, facet joint injections, or ligamentous (sclerosant) injections are not indicated.
REFERENCES: Garfin SR, Vaccaro AR (eds): Orthopaedic Knowledge Update: Spine. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1997, Appendix A15.
Helfgott SM: Sensible approach to low back pain. Bull Rheum Dis 2001;3:50.

Question 26

Which gene mutation or polymorphism has been shown to most increase the risk for venous thromboembolic disease after elective total joint arthroplasty?

Explanation

DISCUSSION
Simultaneous bilateral TKA accounts for approximately 6% of the TKAs performed in the United States and is more frequently performed for women. The incidence of pulmonary embolism in this group was between 0.57 and 1.14, according to a 1999 to 2008 registry-based study in the United States. There was not a significant change in incidence during that period. Hypoxemia alone is not an indication for advanced testing for pulmonary embolism. Winters and associates demonstrated that to avoid unnecessary testing, the use of a hypoxia algorithm is a reasonable first step. The use of pharmacologic agents and/or mechanical compressive devices for the prevention of venous thromboembolism in patients undergoing elective hip or knee arthroplasty and who are not at elevated risk beyond that of the surgery itself for venous thromboembolism or bleeding was given a Moderate grade of recommendation in the 2011 AAOS Clinical Practice Guideline, Preventing Venous Thromboembolic Disease in Patients Undergoing Elective Hip and Knee Arthroplasty. Various genetic factors are associated with increased risk for venous thromboembolic disease after TKA. A recent meta-analysis evaluated the genetic and polymorphism profiles associated with venous thromboembolism after arthroplasty. The mutation MTHFR/C677T/TT carried the highest risk (OR 2.36; 95% CI, 1.03-5.42, P = 0.04) for the gene mutations and polymorphisms studied. With the increased use of TXA as a blood-conservation strategy for total joint arthroplasty, there is a theoretical concern about an increased risk for venous thromboembolic disease. A recent study by Duncan and associates included 13,262 elective total joint arthroplasty procedures and demonstrated that TXA does not increase the risk of venous thromboembolism.

Question 27

Denosumab, a monoclonal antibody used to treat osteoporosis, works through inhibition of

Explanation

Denosumab is a monoclonal antibody that targets and inhibits RANKL binding to the RANK receptor, which is found on osteoclasts. As a result, it inhibits activation of osteoclast cells and slows the process of bone resorption and bone turnover via osteoclast inhibition. The end result is similar to bisphosphonates in terms of effector cell, but the mechanism of action is very different. RANKL binds to RANK, but OPG inhibits RANK binding to RANKL. TNF is an inflammatory cytokine, and monoclonal antibodies to TNF are used to treat systemic inflammatory disease such as rheumatoid arthritis.

Question 28

Which of the following is true regarding plating of humeral shaft fractures compared to intramedullary nailing?

Explanation

DISCUSSION: Lin et al found less blood loss with intramedullary nailing than plating, but nailing was also associated with increased shoulder surgery due to disruption of the rotator cuff tendon during insertion. Meekers et al found a higher union rate, better functional results and a lower reoperation rate after plate and screw fixation versus nailing. They concluded that plating was superior in most cases of humeral shaft fracture, except for pathological fractures, very obese patients, and open fractures.

Question 29

A sagittal T1-weighted MRI scan of the knee joint is shown in Figure 23. What structure is identified by the arrow?

Explanation

DISCUSSION: On T1-weighted images, the posterior cruciate ligament is a low-signal (black) structure that courses from the posterior aspect of the tibia to the medial femoral condyle. The posterior cruciate ligament can appear as arcuate, U-shaped, or kinked. The other structures have similar signal but different anatomic locations.
REFERENCES: Gross ML, Grover JS, Bassett LW, Seeger LL, Finerman GA: Magnetic resonance imaging of the posterior cruciate ligament: Clinical use to improve diagnostic accuracy. Am J Sports Med 1992;20:732-737.
Sonin AH, Fitzgerald SW, Friedman H, Hoff FL, Hendrix RW, Rogers LF: Posterior cruciate ligament injury: MR imaging diagnosis and patterns of injury. Radiology 1994;190:455-458.

Question 30

..Figure 93 is the radiograph of a 72-year-old woman. Treatment includes fixation of the ulna. What options are recommended for the radius?

Explanation

CLINICAL SITUATION FOR QUESTIONS 94 THROUGH 96

Figure 94 is the anteroposterior radiograph of a 75-year-old woman who has a 5-year history of progressive pain, crepitus, and loss of motion in her shoulder. She had a rotator cuff repair 10 years ago. Examination reveals 60 degrees of active forward elevation and 20 degrees of external rotation with her arm at her side. Passively she can be brought to 160 degrees of forward elevation and 90 degrees of external rotation with her arm at her side. A glenohumeral joint injection with local anesthetic eliminated pain, but there is no observed change in active motion.

Question 31

What is the most common physical finding in a patient with femoroacetabular impingement (FAI)? Review Topic

Explanation

A loss of flexion and internal rotation are hallmarks of FAI. With the hip flexed 90 degrees, maximal internal rotation testing is also known as the anterior impingement test, causing deep groin pain and reproduction of symptoms. Occasionally, a posterior impingement test will be positive with extension and external rotation. There are a variety of causes of FAI; however, the pathology limits motion as the femur (cam) and acetabulum (pincer) contact one another. Also, only one location needs to be present, such as cam-type or pincer-type versus both cam-pincer lesions to cause symptoms.

Question 32

A 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 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 33

A 28-year-old woman who is an avid runner reports pain about the left hip with activities. Nonsurgical management has failed to provide relief. An MRI arthrogram is shown in Figure 47. What is the most likely diagnosis?

Explanation

DISCUSSION: The MRI arthrogram reveals dye extravasation into the labrum, consistent with a labral tear. The MRI findings are not typical of osteonecrosis, stress fracture, or transient osteoporosis. There is no increase in bone marrow edema in the neck or femoral head.
REFERENCES: Guanche CA, Sikka RS: Acetabular labral tears with underlying chondralmalacia: A possible association with high-level running. Arthroscopy 2005;21:580-585.
McCarthy JC: The diagnosis and treatment of labral and chondral injuries. Instr Course Lect 2004;53:573-577.

Question 34

Figures 13a and 13b show the MRI scans of a 70-year-old patient who has a posterior calf mass. Examination reveals that the mass extends to the midcalf level. A biopsy specimen reveals a high-grade soft-tissue sarcoma. Metastatic work-up shows no lesions. Management should consist of

Explanation

DISCUSSION: Soft-tissue sarcomas generally are treated with radiation therapy and wide surgical resection. In this patient, involvement of most of the posterior calf compartment and circumferential involvement of the posterior tibial and peroneal neurovascular bundle makes limb salvage impractical. Any attempt at wide surgical resection would leave a poorly functioning limb with questionable surgical margins. A high below-knee amputation would be the best option. Radiation therapy alone is contraindicated.
REFERENCES: Lindberg RD, Martin RG, Romsdahl MM, et al: Conservative surgery and post-operative radiotherapy in 300 adults with soft tissue sarcoma. Cancer 1981;47:2391-2397.
Sim FT, Frassica FS, Frassica DA: Soft tissue tumors: Diagnosis, evaluation, and management. J Am Acad Orthop Surg 1994;2:202-211.
Rosenberg SA, Tepper J, Glatstein E, et al: The treatment of soft-tissue sarcomas of the extremities: Prospective randomized evaluations of (1) limb sparing surgery plus radiation therapy compared with amputation and (2) The roll of adjuvant chemotherapy. Am Surg 1982;196:305-315.

Question 35

Which of the following positions of immobilization has been shown to best approximate the anterior labrum against the glenoid rim following anterior dislocation of the shoulder?

Explanation

DISCUSSION: Following anterior dislocation of the shoulder, the affected arm is typically placed in a sling with the shoulder in adduction and internal rotation. A recent study has shown that placement in this position actually results in laxity of the anterior supporting structures of the shoulder, allowing the postinjury hemarthrosis to push the labrum and capsular ligaments away from the anterior glenoid rim. Thus, immobilization in this position may actually impede healing of these structures. Alternatively, resting the arm in a position of adduction and external rotation allows the anterior supporting structures to abut against the anterior glenoid rim by forcing the hemarthrosis posteriorly. Placing the arm in this position following anterior dislocation is believed to allow for better healing of the anterior labrum and ligaments.
REFERENCE: Itoi E, Sashi R, Minagawa H, et al: Position of immobilization after dislocation of the glenohumeral joint: A study with use of magnetic resonance imaging. J Bone Joint Surg Am 2002;84:873-874.

Question 36

Figures 4a through 4c show the radiographs of a 43-year-old woman who sustained a twisting injury to her right ankle. She has ankle pain and tenderness medially and laterally. To help determine the optimal treatment, an external rotation stress radiograph of the ankle is obtained. This test is designed to evaluate the integrity of what structure?

Explanation

DISCUSSION: In the presence of a supination external rotation-type fracture of the distal fibula (Weber type B), stability of the ankle is best assessed by performing an external rotation stress AP view of the ankle. This test is used to assess the integrity of the deltoid ligament. The presence of a deltoid ligament rupture results in instability and generally is best managed surgically. The gravity stress test can also be used.
REFERENCES: Egol KA, Amirtharajah M, Tejwani NC, et al: Ankle stress test for predicting the need for surgical fixation of isolated fibular fractures. J Bone Joint Surg Am 2004;86:2393-2398.
McConnell T, Creevy W, Tornetta P III: Stress examination of supination external rotation-type fibular fractures. J Bone Joint Surg Am 2004;86:2171-2178.
Schock HJ, Pinzur M, Manion L, et al: The use of the gravity or manual-stress radiographs in the assessment of supination-external rotation fractures of the ankle. J Bone Joint Surg Br 2007;89:1055-1059.

Question 37

What complication is frequently associated with the Weil lesser metatarsal osteotomy (distal, oblique) in the treatment of claw toe deformities?

Explanation

DISCUSSION: Weil osteotomies are useful in achieving shortening of a lesser metatarsal with preservation of the distal articular surface. The osteotomy is oriented from distal-dorsal to proximal-plantar; therefore, proximal displacement of the distal fragment is associated with plantar (not dorsal) displacement as well. Plantar displacement can result in the intrinsics acting dorsal to the center of the metatarsophalangeal joint and the development of an extended or “floating toe.” Nonunion, osteonecrosis, and inadequate shortening are infrequent complications associated with the Weil lesser metatarsal osteotomy.
REFERENCES: Trnka HJ, Nyska M, Parks BG, et al: Dorsiflexion contracture after the Weil osteotomy: Results of cadaver study and three-dimensional analysis. Foot Ankle Int

2001;22:47-50.
Trnka HJ, Muhlbauer M, Zettl R, et al: Comparison of the results of the Weil and Helal osteotomies for the treatment of metatarsalgia secondary to dislocation of the lesser metatarsophalangeal joints. Foot Ankle Int 1999;20:72-79.

Question 38

A 20-year-old football player sustains a dorsiflexion external rotation injury to his right ankle. During sideline evaluation, which of the following findings best indicates a syndesmosis ankle sprain without diastasis?

Explanation

DISCUSSION: The inability to single leg hop is considered the best indicator of a syndesmosis ankle sprain without diastasis. Tenderness along the syndesmosis, the deltoid, or over the anterior talofibular ligament or anterior distal tibia/fibula may present later, following the initial injury. The squeeze test and tenderness with dorsiflexion and external rotation may be positive but often are not present initially. The best determinant for prediction of return to play is the amount of tenderness along the syndesmosis, measured from the distal fibula up the syndesmosis.
REFERENCES: Nussbaum ED, Hosea TM, et al: Prospective evaluation of syndesmosis ankle sprains without diastasis. Am J Sports Med 2001;29:31-35.
Miller CD, Shelton WR, Barrett GR, et al: Deltoid and syndesmosis ligament injury of the ankle without fracture. Am J Sports Med 1985;23:746-750.
Amendola A: Controversies in diagnosis and management of syndesmosis injuries of the ankle. Foot Ankle 1992;13:44-50.

Question 39

What is the most important consideration in the preoperative evaluation of a child with polyarticular or systemic juvenile rheumatoid arthritis (JRA)?

Explanation

The cervical spine may be involved in a child with polyarticular or systemic JRA; fusion or instability can occur. Radiographic assessment of the cervical spine should include lateral flexion-extension views. The potential exists for spinal cord injury during intubation or positioning in the presence of an unstable cervical spine. Limitations of the TMJ and micrognathia may affect ease of intubation and administration of anesthesia via a mask. If the TMJ and jaw are involved, some patients may have dental findings such as dental caries and even abscesses which can affect surgery. Some children, particularly those with systemic arthritis, may be taking corticosteroids long-term and may need stress dosing with complex surgeries. Although it is important to routinely check for uveitis and iritis in children with JRA,
this usually is not needed preoperatively. Uveitis and iritis are less likely in a child with systemic JRA.

Question 40

In long-term follow-up studies of cemented total knee arthroplasty (TKA), the lowest rates of osteolysis have been associated with which design feature?

Explanation

DISCUSSION
The lowest reported rates of osteolysis involving cemented TKAs are associated with monolithic tibial components. Modular components and cemented metal-backed patella components are associated with a high prevalence of backside tibial insert wear and osteolysis.

Question 41

Figure 36a shows the current radiograph of a 65-year-old woman who slipped and fell. History reveals that prior to the fall she was actively functioning without pain. Figure 36b shows a radiograph obtained 1 year ago. Based on the fracture pattern, the failure is most likely related to

Explanation

DISCUSSION: The radiograph shows a fracture distal to the prosthesis in a stable, apparently well-fixed prosthetic stem. The well-fixed prosthesis-bone composite is stiff, creating a modulus mismatch between the proximal and distal femur. Therefore, the risk of fracture, particularly in osteoporotic bone, is increased at this level. Revision of the stem to a longer construct is unnecessary, and standard plate and screw fixation has been shown to yield union rates of greater than 90%. Nonsurgical treatment of fractures distal to the tip of the prosthesis results in high nonunion rates, reported to be from 25% to 42%.
REFERENCES: Johansson JE, McBroom R, Barrington TW, Hunter GA: Fracture of the ipsilateral femur in patients with total hip replacement. J Bone Joint Surg Am 1981;63:1435-1442.
Bethea JS III, DeAndrade JR, Fleming LL, Lindenbaum SD, Welch RB: Proximal femoral fractures following total hip arthroplasty. Clin Orthop 1982;170:95-106.
Garbuz DS, Masri BA, Duncan CP: Periprosthetic fractures of the femur: Principles of prevention and management, in Cannon WD Jr (ed): Instructional Course Lectures 47. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1998, pp 237-242.

Question 42

A 15-year-old girl sustained the injury shown in Figures 70a and 70b when she jumped from the back of a moving truck. She is seen in the emergency department 2 hours after her injury. She has no other injuries. Her foot is warm and she has a normal motor and sensory examination. Pulses are only evident on Doppler. What is the most appropriate management? Review Topic

Explanation

The radiographs reveal a distal femoral fracture that is often associated with a neurovascular injury at the level of the fracture. Initial treatment should be to reduce the fracture, stabilize it, and then reevaluate the extremity for neurovascular function. A CT scan, arteriogram, or MRI scan would not help and would delay treatment. A cast would not be appropriate because access to the extremity is necessary and it would not provide stabilization for vascular repair if it is required.

Question 43

A 74-year-old woman has had acute medial right knee pain for the past 3 months. She denies any history of trauma or previous problems. Coronal and sagittal MRI scans are shown in Figures 11a and 11b. What is the most likely diagnosis? Review Topic

Explanation

Spontaneous osteonecrosis of the medial femoral condyle is seen in the MRI scans, and is most common in women older than age 60 years. Although usually present in the weight-bearing portion of the medial femoral condyle, spontaneous osteonecrosis has also been described involving the lateral femoral condyle and patella. Most patients are seen postcollapse, and the treatment of choice is arthroplasty. Optimal treatment in precollapse stages is controversial.

Question 44

A 45-year-old woman with a long-standing history of diabetes mellitus has a large draining plantar ulcer of the right foot. Examination reveals some local cellulitis and erythema surrounding the ulcer. A clinical photograph is shown in Figure 7. Based on these findings, what is the most appropriate antibiotic?

Explanation

DISCUSSION: Combination drugs with activity against both aerobic and anaerobic organisms have been determined to be the best approach. The first-generation cephalosporins do not provide adequate coverage for gram-negative and anaerobic organisms. Gentamicin alone would not provide adequate activity against anaerobes, and there is the risk of renal and auditory toxicity.
REFERENCES: Pinzur MS, Slovenkai MD, Trepman E: Guidelines for diabetic foot care. Foot Ankle Int 1999;20:695-702.
Eckman MH, Greenfield S, Mackey WC, et al: Foot infections in diabetic patients: Decision and cost-effectiveness analyses. JAMA 1995;273:712-720.

Question 45

Figures 8a and 8b show the current radiographs of a 10-year-old boy with a hip disorder who was treated with an abduction orthosis 3 years ago. If no further remodeling occurs, what is the most likely prognosis?

Explanation

DISCUSSION: The radiographs show a child with Legg-Calve-Perthes disease (LCPD) that has healed. Deformity (asphericity) of the femoral head is evident, but the femoral head and acetabulum are congruous. Stulberg and associates found that hips with aspherical congruity at skeletal maturity functioned well until the fifth or sixth decade of life. Similarly, another study found that degenerative arthritis caused deteriorating hip function after age 40 years in patients with this degree of residual deformity. Repeated episodes of ischemic necrosis are unlikely. Although some studies suggested coagulation abnormalities such as protein C and S deficiencies in children with LCPD, other studies failed to show any evidence of inherited thrombophila in most children with this disorder. There are no studies to suggest growth acceleration occurs following LCPD.
REFERENCES: Stulberg SD, Cooperman DR, Wallenstein R: The natural history of Legg-Calve-Perthes disease. J Bone Joint Surg Am 1984;66:479-489.
McAndrew MP, Weinstein SL: A long-term follow-up of Legg-Calve-Perthes disease. J Bone Joint Surg Am 1984;66:860-869.

Question 46

What is the prognosis for ambulation, from best to worst, for patients with an incomplete spinal cord injury?

Explanation

DISCUSSION: Of the incomplete spinal cord injuries, Brown-Sequard syndrome has the best prognosis for ambulation. Central cord syndrome has a variable recovery. Anterior cord syndrome has the worst prognosis, with motor recovery rare below the level of the injury.
REFERENCES: Apple DF: Spinal cord injury rehabilitation, in Herkowitz HN, Garfin SR, Balderston RA, Eismont FJ, Bell GR, Wiesel SW (eds): Rothman-Simeone The Spine, ed 4. Philadelphia, PA, WB Saunders, 1999, pp 1130-1131.
Northrup BE: Evaluation and early treatment of acute injuries to the spine and spinal cord, in Clark CR (ed): The Cervical Spine, ed 3. Philadelphia, PA, Lippincott Raven, 1998, pp 544-545.

Question 47

Emergent management of acute tooth displacement (luxation) includes

Explanation

DISCUSSION: Avulsed teeth must be replanted immediately to enhance viability of the periodontal ligament cells on the root. With the tooth in place, the athlete should bite down on a towel to maintain stability. The athlete should be taken emergently to a dentist’s office or emergency room. The avulsed tooth should not be handled by the root or scrubbed to remove debris. If immediate replantation is not possible, the tooth should be transported in saline solution, milk, or saliva on gauze.
REFERENCES: Flores MT, Andreasen JO, Bakland LK, et al: Guidelines for the evaluation and management of traumatic dental injuries. Dent Traumatol 2001; 17:97-102.
Ranalli DN, Demas PN: Orofacial injuries from sport preventive measures for sports medicine. Sports Med
2002;2:409-418.

Question 48

A 65-year-old man undergoes L4-L5 laminectomy and instrumented fusion for lumbar spinal stenosis. Post procedure radiograph is shown in figure A. Postoperatively, he develops numbness and tingling along the lateral aspect of his thigh with no associated foot symptoms or weakness. Which of the following is the most likely cause of this finding? Review Topic

Explanation

During lumbar laminectomy and instrumented fusion, patients are in prone position with padded rests near the iliac crest. The lateral femoral cutaenous nerve (LFCN) is at risk of compression during surgery due to positioning.
Careful patient position during orthopaedic surgery is of the utmost importance to prevent nerve injury. When patients are placed lateral for hip procedures, adequate positioning and padding of bony prominences and nerves is necessary to prevent complications. During prone position for spine surgery, the lateral femoral cutaneous nerve can be compressed under the iliac crest padded rest leading to meralgia parasthetica (MP). Numbness and tingling over the lateral thigh are usually temporary. The ulnar nerve at the elbow can also be at risk due to pressure from the positioning of the arms and the brachial plexus can be compromised by possible stretch.
Cho et al. review the literature regarding development of paresthesia due to compression of the LFCN after prone positioning for spinal surgery. They reported up to 24% incidence of after surgery. Surgery longer than 3.5 hours and shorter distance between the pelvic posts were implicated in development of MP. They recommened the patient should be positioned symmetrically, with smaller bolsters under the ASIS and adequate distance between the two pelvic posts.
Labrom et al. examined the use of SSEPs during scoliosis surgery to evaluate positional-related brachial plexopathy. They found that 27 of 434 patients had 30 percent or greater loss of SSEP during surgery. There was a significant association with prone versus supine positioning (p<0.01).
Schwartz et al. used neurological monitoring to identify the incidence and location of position-induced nerve injury in anterior cervical spine surgery. 1.8% of 3806 patients showed evidence of impending neurological injury. The majority of these cases were
at the brachial plexus during shoulder taping and application of counter traction.
Figure A is an AP lumbar spine radiograph showing intact hardware from L4-L5 laminectomy and fusion.
Incorrect

Question 49

A 65-year-old woman with type II diabetes mellitus (most recent Hgb A1C was 8.2) has had 3 days of left knee pain. Physical examination of the left knee reveals erythema, warmth and a large effusion. Range of motion is painful and limited to 30 degrees of flexion. She is found to be hypotensive and not responding to volume resuscitation. She requires phenylephrine to maintain Mean Arterial Pressure (MAP) of 70. ESR and CRP are elevated and Lactate is 3.1 mmol/L. What is the next best intervention for this patient’s treatment?

Explanation

Discussion: The patient is demonstrating signs of septic shock. Administration of antibiotics should not be delayed. Aspirating the knee joint and obtaining blood cultures can be rapidly accomplished to obtain accurate specimens. This should be followed immediately by administration of broad spectrum IV antibiotics. Patients with septic shock can be identified with a clinical construct of sepsis with persisting hypotension requiring vasopressors to maintain mean arterial pressure (MAP) ≥ 65 mmHg and having a serum lactate level > 2mmol/L (18 mg/dL) despite adequate volume resuscitation. With these criteria, hospital mortality is in excess of 40%.

Question 50

What preoperative factor correlates best with the outcome of rotator cuff repair?

Explanation

DISCUSSION: The size of the rotator cuff tear in both anteroposterior and mediolateral dimensions has been found to correlate best with outcome. Older patient age and rupture of the long head of the biceps tend to be associated with larger tears and, therefore, may be associated indirectly with a poorer outcome.
REFERENCES: Iannotti JP: Full-thickness rotator cuff tears: Factors affecting surgical outcome. J Am Acad Orthop Surg 1994;2:87-95.
Iannotti JP, Bernot MP, Kuhlman JR, Kelley MJ, Williams GR: Postoperative assessment of shoulder function: A prospective study of full-thickness rotator cuff tears. J Shoulder Elbow Surg 1996;5:449-457.

Question 51

Porous hydroxyapatite is placed into a bone defect. Incorporation of this bone graft substitute is expected to follow which of the following patterns?

Explanation

Porous hydroxyapatite is created via a hydrothermal chemical exchange with phosphate of the calcium carbonate exoskeleton of ocean corals. This process converts the original exoskeleton into an inorganic replica of hydroxyapatite. The porous structure allows neovascularization and new bone is deposited on the macrostructure via appositional bone deposition. The hydroxyapatite does not dissolve and is not removed via creeping substitution. Creeping substitution relies on osteoclastic resorption creating a cutting cone followed by osteoblastic bone formation. The macrostructure of porous hydroxyapatite allows full penetration of osteoblasts and vascularization, not just to the periphery. Inorganic hydroxyapatite does not induce an inflammatory response.

Question 52

Which of the following situations is most likely to decrease sentinel event errors?

Explanation

Creating an environment where all members of the healthcare team feel empowered to express their beliefs increases communication, the key element in decreasing sentinel events.
Research has shown that 70% of sentinel event errors are caused by improper communication. Specific ways to improve communication include effective clinical handover between shifts and breaking down the "hierarchy" so that all members of the team can discuss their expectations and concerns. Barriers to effective communication include distractions, cultural differences, power distance relationships, time pressures, and lack of organization.
Leonard et al. describe specific clinical experiences in the application of surgical briefings, properties of high reliability perinatal care, the value of critical event training and simulation, and benefits of a standardised communication process in the care of patients transferred from hospitals to skilled nursing facilities. They recommend embedding standardized tools and behaviors to bridge differences in communications styles between clinicians.
Incorrect Answers:

Question 53

Figure 24 shows the radiograph of a 47-year-old woman who has severe right hip pain and a limp. Management should consist of

Explanation

DISCUSSION: Femoral shortening osteotomy for a Crowe type IV hip dislocation has been shown to provide superior results with minimal complications. Cementless fixation of the stem allows for modular implants that greatly simplify the reconstruction.
REFERENCE: Jaroszynski G, Woodgate IG, Saleh KJ, Gross AE: Total hip replacement for the dislocated hip. Instr Course Lect 2001;50:307-316.

Question 54

A 70-year-old woman is brought to the emergency department with a two-part greater tuberosity fracture with an anterior subcoracoid dislocation. One day after successful closed reduction, examination reveals marked swelling of the involved arm, forearm, and hand, as well as large amounts of “weeping” serous fluid but no obvious lacerations. The fingers are warm and pink, and the pulses are normal distally with good refill. Edema is present. There is no pain with passive and active motion of the elbow, wrist, and fingers. What is the next most appropriate step in management?

Explanation

DISCUSSION: Although not as common as arterial injury, venous thrombosis secondary to trauma of the subclavian or axillary vein can be problematic; therefore, venous duplex ultrasound scanning is the diagnostic study of choice. Arteriography may not show venous thrombosis in the venous run-off phase. The clinical history does not fit the usual presentation of a compartment syndrome or complex regional pain syndrome.
REFERENCE: Killewich LA, Bedford GR, Black KW, et al: Diagnosis of deep venous thrombosis: A prospective study comparing duplex scanning to contrast venography.

Circulation 1989;79:810.

Question 55

What is the most appropriate treatment?

Explanation

DISCUSSION
A common postsurgical problem after TKA is a sudden increase of pain that typically occurs about 2 to 3 weeks after surgery. ESR findings are not reliable during the acute postsurgical period. A CRP level exceeding 100 mg/L during the acute postsurgical period is a joint aspiration indication. If the patient does not have sepsis, there is no emergency. This pain is likely attributable to too much activity during physical therapy. Observation is recommended for this patient.

Question 56

An 80-year-old man has had increasing shoulder pain for the past 4 months. He reports that it began with soreness and stiffness after chopping some wood. A coronal MRI scan is shown in Figure 16. Initial management should consist of

Explanation

DISCUSSION: The MRI scan shows a massive tear of the supraspinatus tendon with medial retraction to the level of the glenoid. This is most likely an attritional tear with a high risk of failure of the repair. The preferred treatment is nonsurgical management for pain and stiffness. Acromioplasty and coracoacromial ligament release in this setting are controversial, as they can result in the devastating complication of anterosuperior subluxation of the humerus.
REFERENCES: Rockwood CA Jr, Williams GR Jr, Burkhead WZ Jr: Debridement of degenerative, irreparable lesions of the rotator cuff. J Bone Joint Surg Am 1995;77:857-866.
Beaty JH (ed): Orthopaedic Knowledge Update 6. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1999, pp 299-312.

Question 57

A 50-year-old man fell from a ladder onto his left shoulder and sustained the injury shown in the radiographs in Figures 71a and 71b. He underwent surgery with repair of the coracoclavicular ligaments and deltotrapezial fascia with coracoclavicular screw placement. Which of the following statements regarding postoperative complications is most accurate? Review Topic

Explanation

Whereas pain and functional disturbance may persist with nonsurgical management, the lack of articular surface contact prevents arthritic symptoms from developing. Cartilage injury caused by trauma and any persistent joint incongruity following repair would contribute to posttraumatic arthritis. Pinning across the acromioclavicular joint has a high incidence of hardware migration and potential catastrophic consequences. Most cases of lost fixation of coracoclavicular screws are at the level of the thread purchase in the coracoid. Routine hardware removal at 8 to 12 weeks is recommended to avoid screw breakage because of natural movement between the clavicle and scapula. The axillary nerve passes around the inferior edge of the subscapularis and is anatomically distant to the the coracoid. The musculocutaneous nerve would have the closest anatomic position to the coracoid.

Question 58

When using the direct lateral (or Hardinge) approach for hip arthroplasty, three muscles are detached from the femur. In addition to the vastus lateralis, they include the

Explanation

DISCUSSION: This approach is criticized for the episodic limp associated with the muscle detachment and reattachment. Classically, two thirds of the gluteus medius is detached as a sleeve with the vastus lateralis. This exposes the gluteus minimus and the ligament of Bigelow. These must also be detached to allow dislocation of the hip and osteotomy of the femoral neck. The rectus femoris lies medially and anteriorly and does not need to be addressed. The piriformis and obturator internus are exposed during the posterior approach. Neither the gluteus maximus nor tensor fascia lata attach to the anterior femur. The sartorius and iliopsoas are not exposed during this dissection.
REFERENCES: Hoppenfeld S, deBoer P (eds): Surgical Exposures in Orthopaedics: The Anatomic Approach. Philadelphia, PA, JB Lippincott, 1984, pp 333-335.
Hardinge K: The direct lateral approach to the hip. J Bone Joint Surg Br 1982;64:17-19.

Question 59

Figure 56 is the radiograph of an otherwise healthy 3-year-old boy who fell and sustained the isolated injury shown. What is the best treatment modality?

Explanation

DISCUSSION
At 3 years of age, children do well with nonsurgical treatment with early spica casting and early mobilization. There is no indication to perform surgical stabilization in such a closed isolated injury. The fracture is not shortened unacceptably according to clinical practice guidelines, and traction for this fracture is unnecessary. Traction also may be problematic for the family and healthcare system.
RESPONSES FOR QUESTIONS 57 THROUGH 62
Cortical thickening in the region of the lesion
Erosive metaphyseal lesion with loss of cortical integrity
Normal bony anatomy on radiographs
Diffuse articular erosion with loss of joint space
Round, expansive, well-circumscribed metaphyseal lesion with thinning of the cortex
Eccentric well-circumscribed metaphyseal lesion with a scalloped border
Match the orthopaedic condition described below with the expected radiographic finding listed above.

Question 60

Glenohumeral inferior stability in the adducted shoulder position is primarily a function of the

Explanation

DISCUSSION: When the arm is adducted, the superior structures, including the superior glenohumeral ligament, are responsible in limiting the inferior translation. With the arm abducted, the inferior glenohumeral ligament complex is responsible for limiting inferior subluxation. Rotator cuff activity can actually depress the humeral head and does not play a role in preventing inferior subluxation. The long head of the biceps and the posterior glenohumeral ligament do not play a role in protecting the shoulder from inferior instability.
REFERENCES: Warner JJ, Deng XH, Warren RF, Torzilli PA: Static capsuloligamentous restraints to superior-inferior translation of the glenohumeral joint. Am J Sports Med 1992;20:675-685.
Harryman DT II, Sidles JA, Harris SL, Matsen FA III: The role of the rotator interval capsule in passive motion and stability of the shoulder. J Bone Joint Surg Am 1992;74:53-66.

Question 61

A 68-year-old man presents with severe right shoulder pain. He had a prolonged course of physical therapy and received several cortisone injections for his pain without improvement. Examination reveals pseudoparalysis of the right shoulder with a 20-degree external rotation lag with the shoulder adducted. With the shoulder placed in 90 degrees of abduction, he can actively externally rotate his shoulder. The patient was treated with a medialized reverse prosthesis shown in Figure A. Which of the following statement is true regarding this treatment option? Review Topic

Explanation

The clinical presentation is consistent with a patient with pseudoparalysis that was treated with a reverse total shoulder arthroplasty (RTSA). The risk of postoperative instability is increased in patients with an irrepairable subscapularis when a medialized reverse prosthesis is used. Answers 1-4 are false statements.
RTSA is most commonly indicated for rotator cuff arthropathy. However, indications for use now include shoulder pseudoparalysis, anterosuperior escape of the humeral head, acute 3 or 4-part proximal humerus fractures, and greater tuberosity fracture nonunions. Contraindications to RTSA included deltoid dysfunction, insufficient glenoid bone stock, and bony deficiency of the acromion.
Edwards et al. prospectively evaluated the risk of shoulder dislocation after reverse TSA. They found a significantly increased risk of dislocation (p=0.012) in patients with an irreparable subscapularis at time of surgery. There were no dislocations in the reparable group. Dislocations were more likely in patients with proximal humeral nonunions and failed prior arthroplasty.
Mulieri et al. looked at the use of reverse TSA in patients with irreparable massive rotator cuff tears without evidence of glenohumeral arthritis. All outcomes were improved postoperatively, and they advocate for reverse TSA in this subset of patients. Survivorship was over 90% at more than 4 years average follow up.
Boileau et al. evaluated the clinical outcomes of isolated biceps tenotomy/tenodesis in patients with massive rotator cuff tears and a biceps lesion. They found that the procedure can effectively treat pain and improve function in these patients. There was no difference in patients undergoing tenotomy versus tenodesis.
Figure A is a right shoulder radiograph status post RTSA with components in adequate position.
Incorrect Answers:

Question 62

What role does quorum sensing play in the development of a bacterial biofilm?

Explanation

The development of a bacterial biofilm is a 2-stage process. The first step is the adhesion of individual bacteria to a substrate regulated by adhesions. After several bacteria have attached, quorum sensing (cell-to-cell communication) allows maturation of the biofilm and expression of genes that activate virulence factors. This can also increase the antibacterial resistance of the bacteria. Planktonic bacteria are individual free-moving bacteria.

Question 63

Figure 24 shows the radiograph of a 4-year-old girl with spina bifida. Examination reveals an L3 motor level, excellent sitting and standing balance, and satisfactory range of motion at the hips. Management should consist of

Explanation

DISCUSSION: Children with spina bifida and bilateral symmetrical dislocation of the hips usually do not require treatment. A level pelvis and good range of motion of the hips are more important for ambulation than reduction of bilateral hip dislocations. Because the patient has good sitting and standing balance and good range of motion, maintenance of that range of motion and symmetry is more important than reduction. Surgery is not recommended.
REFERENCE: Heeg M, Broughton NS, Menelaus MB: Bilateral dislocation of the hip in spina bifida: A long-term follow-up study. J Pediatr Orthop 1998;18:434-436.

Question 64

Figures below show the clinical photograph and radiograph obtained from a 62-year-old man who has deformity and pain 1 year after primary total hip arthroplasty. What is the reason for the observed deformity?

Explanation

DISCUSSION:
Figure 1 reveals an external rotation deformity of the right lower extremity. This deformity can have numerous causes, including extra-articular deformity. Figure 2 reveals a loose, subsided femoral component. Femoral stems typically subside into retroversion due to proximal femoral biomechanics, which cause a compensatory external rotation deformity. The combined findings from both images suggest an external rotation deformity most likely related to subsidence into retroversion.

Question 65

An 81-year-old man with severe low back pain reports right extensor hallucis longus and anterior tibialis weakness and difficulty urinating over the past 24 hours. He has a temperature of 101 degrees F (38.3 degrees C). MRI scans are shown in Figures 31a and 31b. Management should consist of

Explanation

DISCUSSION: An epidural abscess with neurologic deficit represents a medical and surgical emergency. The prognosis is related to the timeliness of diagnosis and treatment. Once identified, the primary treatment is surgical decompression of the abscess, followed by organism-specific antibiotics. In the absence of a significant anterior process such as diskitis or vertebral osteomyelitis, lumbar epidural abscesses generally can be drained through a posterior approach. Delayed stabilization usually is not required unless, in the course of decompression, removal of too much of the facets creates an instability; this is an uncommon occurrence.
REFERENCES: Garfin SR, Vaccaro AR (eds): Orthopaedic Knowledge Update: Spine. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1997, pp 257-271.
Reihsaus E, Waldbaur H, Seeling W: Spinal epidural abscess: A meta-analysis of 915 patients. Neurosurg Rev 2000;23:175-204.

Question 66

A 45-year-old woman has severe anterior knee pain. Her radiographs indicate end-stage patellofemoral compartment osteoarthritis. The tibiofemoral compartments are preserved. Extensive nonsurgical treatment has failed to provide relief, and she is offered patellofemoral arthroplasty (PFA). What is the most common long-term mode of failure for PFA using an implant with an onlay prosthesis design?

Explanation

DISCUSSION:
Contemporary onlay-design trochlear prostheses in PFA replace the entire anterior trochlear surface. Previous inlay designs were inset within the native trochlea and carried a higher risk of catching and patellar instability, particularly in patients with trochlear dysplasia; they also generally have higher failure rates. The current most common mode of failure is progression of arthritis throughout the knee, in some series as high as 25% at 15 years. Aseptic loosening, particularly of cemented implants, is less common. Infection is an uncommon long-term complication. Patients considering PFA should be advised of the risk of arthritis progression. Many authors routinely obtain a preoperative MRI to assess the status of the tibiofemoral compartments.

Question 67

Reverse total shoulder arthroplasty improves kinematics in the rotator cuff deficient joint by what directional change to the center of rotation? Review Topic

Explanation

Surgical indications for reverse total shoulder arthroplasty are expanding. In the setting of rotator cuff tear arthroplasty in which the native humeral head migrates superiorly, these implants impart several kinematic advantages. Implant center of rotation medial to the former joint surface improves glenoid component stability as the resultant force vector passes through the component throughout the arc of motion. A stable and fixed fulcrum for elevation is provided by matched radius of curvature between the glenoid and humeral components. A more distal center of rotation increases resting length and tone of the deltoid muscle, improving its effectiveness as a shoulder elevator. Medialized joint center of rotation increases the moment arm of the deltoid, requiring less muscle force to produce a given torque. This results in decreased articular shear stress.

Question 68

Figure 67 shows the AP radiograph of both knees of a 26-year-old woman. A review of the patient’s medical record will most likely reveal a history of

Explanation

Avascular necrosis of the knee is associated with the use of corticosteroids or alcohol 90% of the time. Radiographically evident lesions progress until the necrotic cancellous bone collapses away from the subchondral plate, resulting in the classic crescent sign; earliest sign of mechanical failure of the condyles. Generally seen in a younger age group (less than 50 years old). Of patients with corticosteroid induced AVN of the knee; 81% have systemic lupus erythematosus, 9.5% inflammatory bowel disease, and 9.5% polymyositis.

Question 69

A 2-year-old child is brought in by his parents for evaluation of intoeing. The child has a normal neuromuscular examination, but the heel bisector line is in the fourth web space, indicating a severe flexible metatarsus adductus deformity. The remainder of the lower extremity examination is unremarkable. What is the most appropriate treatment?

Explanation

DISCUSSION: Weinstein reported on 31 patients (45 feet) with congenital metatarsus adductus followed for an average of 33 years. Twenty-nine feet had moderate to severe deformities treated with manipulation and casting with a 90% success rate. In a young child, surgery is not indicated until nonsurgical management has failed. In patients 2 to 4 years of age, tarsometatarsal capsulotomies are indicated, whereas multiple metatarsal osteotomies are reserved for recalcitrant deformities in children older than 4 years of age. Mild or moderate metatarsus adductus that is passively correctable will resolve without treatment.
REFERENCES: Beaty J: Congenital anomalies of the lower extremity, in Canale ST (ed): Campbell’s Operative Orthopaedics, ed 10. Philadelphia PA, Mosby, 2003, pp 983-988.
Katz K, David R, Soudry M: Below-knee plaster cast for the treatment of metatarsus adductus.

J Pediatr Orthop 1999;19:49-50.
Weinstein SL: Bristol-Myers Squibb/Zimmer award for distinguished achievement in orthopaedic research. Long-term follow-up of pediatric orthopaedic conditions: Natural history and outcomes

of treatment. J Bone Joint Surg Am 2000;82:980-990.

Question 70

What is the primary mechanism of wear of polyethylene acetabular components?

Explanation

Although previous theories on acetabuIar wear implicated fatigue cracking and delamination which is a major mode of polywear in knees, the primary mechanism of wear of polyethylene acetabular components has been shown to be adhesion and abrasion. In an analysis of 128 componenets retrieved at autopsy or revision surgery, wear appeared to occur mostly at the surface of the components and to be due to large strain plastic deformation and orientation of the surface layers into fibrils that subsequently ruptured during multidirectional motion. It was also shown conclusively that 32 mm displayed significantly more wear (volumetric wear) than with either 22 or 26/28 mm heads ( 1 mm increase in size increased volumetric wear by 10%). The wear at the articulating surface was characterized by highly worn polished areas superiorly and less worn areas inferiorly separated by a ridge. Abrasion was very common, occurring after adhesion and plastic deformation of poly fibrils, and abrasion secondary to third body wear. As well, wear rates decreased with longer survival of components, indicating a "wearing in" phenomenon, arguing against oxidative and fatigue wear. Crevice corrossion = occurs in fatigue cracks with low 02 tension (under screw heads,etc.) Oscillatorry fretting = cyclical outer surface abrading from small movements. Fatigue and delamination = predominant in total knees, where stresses are maximum just below the surface of the poly, causing fatigue over time with susequent delamination. In contrast, hip wear occurs primarily at the surface of the poly.

Question 71

Which of the following patients requires preoperative noninvasive cardiac testing?

Explanation

DISCUSSION: Noninvasive cardiac testing is recommended in the presence of the three or more of the following risk factors in a sedentary patient: history of coronary artery disease or myocardial infarction, history of heart failure, prior cerebrovascular accident, and diabetes mellitus or chronic renal disease. Preoperative stress testing is not recommended if patients can perform moderate activities such as climbing a flight of stairs.
REFERENCES: Bushnell BD, Horton JK, McDonald MF, et al: Perioperative medical comorbidities in the orthopaedic patient. J Am Acad Orthop Surg 2008;16:216-227.
Auerback A, Goldman L: Assessing and reducing the cardiac risk of noncardiac surgery. Circulation 2006;113:1361-1376.
Fischgrund JS (ed): Orthopaedic Knowledge Update 9. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2008, pp 105-113.

Question 72

A 26-year-old man sustains a displaced bimalleolar fracture by sliding into second base while playing baseball. Following initial closed reduction and splinting of the fracture, moderate swelling is noted. What is the safest time to perform surgery?

Explanation

DISCUSSION: Following any closed fracture, the most important determinant for the timing of surgery is the condition of the soft tissues and especially the skin. The best determinant of appropriate soft-tissue condition is the presence of wrinkling of the skin (wrinkle sign) at the site of the incision. A wrinkle sign is present when all the interstitial edema has left the skin; this may take up to 14 to 21 days of elevation. Any abrasion must be epithelialized so that there are no bacteria left at the site. To date, no other method of soft-tissue viability measurement has been shown to be of any clinical benefit.
REFERENCES: Stover MD, Kellam JF: Articular fractures: Principles, in Ruedi TP, Murphy WM (eds): AO Principles of Fracture Management. Stuttgart, Thieme, 2000, pp 105-119.
Hahn DM, Colton CL, Malleolar fractures, in Ruedi TP, Murphy WM (eds): AO Principles of Fracture Management. Stuttgart, Thieme, 2000, pp 559-581.
Tile M: Fractures of the ankle, in Schatzker J, Tile M (eds): Rationale of Operative Fracture Care, ed 2. Berlin, Springer-Verlag, 1998, pp 523-561.

Question 73

A 35-year-old man sustained a 10% compression fracture of the C5 vertebra in a diving accident. Radiographs show good alignment, and examination reveals no neurologic compromise. An MRI scan reveals no significant soft-tissue disruption posteriorly. Management should consist of

Explanation

DISCUSSION: The patient has a stable flexion-compression injury of the cervical spine. The fracture occurs as a result of compression failure of the vertebral body. If the force continues, a tension failure of the posterior structures occurs, leading to potential dislocation. Immobilization in a rigid cervical orthosis will allow this fracture to heal.
REFERENCES: Clark CR (ed): The Cervical Spine, ed 3. Philadelphia, PA, Lippincott-Raven, 1998, pp 457-464.
Allen GL, 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

Figure 11a shows the clinical photograph of a 46-year old woman who reports a 3-week history of pain and a “lump” at the base of her neck. She is otherwise in good health and denies any trauma. A 3-D reconstruction CT is shown in Figure 11b. What is the most likely diagnosis?

Explanation

DISCUSSION: Spontaneous subluxation of the sternoclavicular joint occurs without any significant trauma. It is usually accentuated by placing the extremity in an overhead position. Discomfort usually resolves within 4 to 6 weeks with nonsurgical management.
REFERENCES: Rockwood CA, Wirth MA: Disorders of the sternoclavicular joint, in Rockwood CA, Matsen FA, Wirth MA, et al (eds): The Shoulder. Philadelphia, PA,

WB Saunders, 2004, vol 2, pp 1078-1079.
Rockwood CA, Odor JM: Spontaneous atraumatic anterior subluxation of the sternoclavicular joint. J Bone Joint Surg Am 1989;71:1280-1288.

Question 75

Persistent symptoms and decreased function following distal clavicle resection, coracoacromial ligament transfer, and augmentation (modified Weaver-Dunn) are most likely related to Review Topic

Explanation

Although multiple studies have reported good clinical results with the modified Weaver-Dunn reconstruction, others have suggested that the reconstruction does not restore the native stability to the acromioclavicular joint. In particular, persistent horizontal (anterior to posterior) instability may cause persistent symptoms following reconstruction. Anatomic repair and reconstruction techniques that preserve the distal clavicle may offer patients less risk of horizontal instability.

Question 76

The incidence of ipsilateral phrenic nerve blockade after an interscalene block approaches

Explanation

DISCUSSION: The most common side effect of an interscalene block is ipsilateral phrenic nerve blockade. The phrenic nerve arises chiefly from the fourth cervical ramus (with contributions from the third and fifth) and is the sole motor supply to the diaphragm. Phrenic nerve palsy usually is well tolerated in healthy patients but should be avoided in patients with limited pulmonary function (severe restrictive or obstructive lung disease, myasthenia gravis, or contralateral hemidiaphragmatic dysfunction). The incidence of ipsilateral phrenic nerve blockade afer interscalene block approaches 100%.
REFERENCES: Long T, Wass C, Burkle C: Perioperative interscalene blockade: An overview of its history and current clinical use. J Clin Anesthesia 2002;14;546-556.
Norris T (ed): Orthopaedic Knowledge Update: Shoulder and Elbow 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 433-442.

Question 77

Progressive paralysis is most likely to be seen in association with what type of congenital vertebral abnormality?

Explanation

DISCUSSION: Anterior failure of formation results in a progressive kyphosis that may lead to cord compression and progressive neurologic deficit. Anterior failure of segmentation can also produce progressive kyphosis but usually is not severe enough to cause cord compression. Posterior failure of formation is seen in conditions such as myelomeningocele in which the neurologic deficit is generally stable. Lateral abnormalities and posterior failure of segmentation are rarely associated with progressive neurologic deficit.
REFERENCES: McMaster MJ, Singh H: Natural history of congenital kyphosis and kyphoscoliosis: A study of one hundred and twelve patients. J Bone Joint Surg Am 1999;81:1367-1383.
Dubousset J: Congenital kyphosis and lordosis, in Weinstein SL (ed): The Pediatric Spine: Principles and Practice, ed 1. New York, NY, Raven Press, 1994, pp 245-258.

Question 78

The diagnosis of an infection after total knee arthroplasty is most reliably proven based on what single study?

Explanation

DISCUSSION: In a study of 52 patients with infected total knee arthroplasties, Windsor and associates showed that the average leukocyte count was 8,300/mm³ and that aspirated knee fluid was positive in all patients except one. Knee radiographs can be unclear in showing infection, which may be present without radiographic signs of loosening. Technetium Tc 99m and gallium bone scans may not conclusively show the presence of infection, particularly in the first 3 years after knee arthroplasty.
REFERENCES: Windsor RE, Bono JV: Infected total knee replacements. J Am Acad Orthop Surg 1994;2:44-53.
Windsor RE, Insall JN, Urs WK, et al: Two-stage reimplantation for the salvage of total knee arthroplasty complicated by infection: Further follow-up and refinement of indications. J Bone Joint Surg Am 1990;72:272-278.

Question 79

A 60-year-old woman has a mass in the right scapula. Figures 25a and 25b show a CT scan and a biopsy specimen. The cells are lymphocyte common antigen positive, Ewing’s specific antigen (CD99) negative, and keratin negative. What is the next step in management?

Explanation

DISCUSSION: The clinical history, CT scan, and histology are most consistent with a lymphoma of bone. An important part of the staging is bone marrow aspiration and biopsy. The other studies listed are not indicated. Lymphoma of bone, when localized, is usually treated with chemotherapy and radiation therapy and has excellent survival rates. Widespread lymphoma has a worse prognosis.
REFERENCES: Finiewicz K, van Biesen K: Non-Hodgkins lymphoma, in Golomb H, Vokes E (eds): Oncologic Therapies, ed 2. Berlin, Germany, Springer, 2003, pp 295-318.
Lems P, Primus G, Anastas J, Doherty D, Montag AG, Peabody TD, Simon MA: Oncologic outcomes of primary lymphoma of bone in adults. Clin Orthop 2003;415:90-97.

Question 80

Figures 1 through 3 are the radiographs of a 27-year-old man who has had wrist pain since falling 1 day ago. Which treatment offers the best prognosis for prevention of carpal collapse and progressive arthritis?

Explanation

EXPLANATION:
Although this patient’s history includes a recent fall, the radiographs show evidence of a scaphoid nonunion with carpal collapse but no arthritis. Obtaining union of the scaphoid is important to prevent progressive carpal collapse and arthritic changes. ORIF with bone graft is most appropriate to obtain union and correct the collapse deformity. Screw fixation with volar wedge graft often is performed to realign a scaphoid humpback deformity, although cancellous bone graft also is a reasonable option. Vascularized bone graft is considered for a nonunion of long duration, avascular necrosis of the proximal pole, and failed prior surgery. Cast immobilization will not lead to union of the scaphoid. Percutaneous screw fixation is not indicated for the treatment of a displaced nonunion. A proximal
row carpectomy is a salvage procedure and is not indicated for this patient because there are no arthritic changes.

Question 81

A 73-year-old man sustains the fracture shown in Figure 62. Which of the following factors or combination of factors puts this patient at highest risk for nonunion if nonsurgical management is used?

Explanation

Most textbooks and early publications list the incidence of complications of nonsurgical treatment of clavicle fractures as very low. However, recent studies on this topic have found an entirely different picture. The studies show that patients reported shoulder weakness and fatigability, upper extremity dysesthesia, and shoulder asymmetry with an incidence of 31%. Indications for surgery in the past have included open fractures, associated neurovascular injury, and widely displaced fractures tenting the skin. Fractures with more than 2 cm of shortening and comminuted fractures with significant displacement have been associated with poor outcomes. Nonunion after nonsurgical management was found to be more common in the study by Robinson and associates in displaced comminuted fractures, in patients with advanced age and female gender.

Question 82

A collegiate football player who sustained a blow to the head during the first quarter of a game is confused for several minutes after the hit but does not lose consciousness. He had two similar episodes in games earlier in the season. When should he be allowed to return to play?

Explanation

DISCUSSION: Using the traditional concussion grading scale, the patient sustained a grade I concussion because he did not lose consciousness and his abnormal cognitive level lasted less than 1 hour. If this was the player’s first concussion, theoretically he could return to play later in the game provided that he had no confusion, headache, or associated symptoms. However, because it was the third concussion for the year, participation in contact sports should be terminated for the season.
REFERENCES: Guskiewwicz KM, Barth JT: Head injuries, in Schenk RC Jr (ed): Athletic Training and Sports Medicine. Rosemont, IL, American Academy of Orthopedic Surgeons, 1999, pp 143-167.
Kelly JP, Rosenberg JH: Diagnosis and management of concussion in sports. Neurology 1997;48:575-580.

Question 83

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 84

An 11-year-old boy sustained an injury to his arm in gym class. He denies prior pain in the arm. Radiographs are shown in Figures 48a and 48b. What is the next most appropriate step in the management of this lesion?

Explanation

DISCUSSION: This radiolucent lesion with a “fallen leaf sign” is typical for a unicameral bone cyst(UBC). The most appropriate treatment is to allow the fracture to heal with clinical and radiographic observation. Curettage and bone grafting is not the best initial management for UBC. Wide resection is not indicated for UBC. The proximal humerus is the most common site for UBC. While staging studies consisting of MRI, bone scan, and CT of the chest are appropriate for lesions suspected of being malignant, the classical appearance of this UBC is such that this work-up is not necessary initially. Following fracture healing, aspiration and injection of the cyst may be indicated.
REFERENCES: Dormans JP, Pill SG: Fractures through bone cysts: Unicameral bone cysts, aneurysmal bone cysts, fibrous cortical defects, and nonossifying fibromas. Instr Course Lect 2002;51:457-467.
Deyoe L, Woodbury DF: Unicameral bone cyst with fracture. Orthopedics 1985;8:529-531.

Question 85

A 35-year-old construction worker continues to have weakness with lifting overhead 2 years after he was treated with physical therapy for a "chest muscle" tear. An obvious deformity noted in his axilla worsens with resisted extension and adduction. A clinical photograph and MRI scan are shown in Figures 119a and 119b. What is the most appropriate treatment? Review Topic

Explanation

This scenario describes a chronic, symptomatic pectoralis major tendon rupture in a young laborer. Direct repair is difficult at this time; therefore, allograft reconstruction is a good alternative to recover strength. Tendon transfers, electrical stimulation, shoulder arthrodesis, and arthroscopy are not indicated in this patient. They will not offer proper reconstruction of the lost muscle tendon unit and/or cosmetic repair.

Question 86

Figures below depict the radiographs obtained from a 76-year-old woman with a painful total knee arthroplasty. She describes an uneventful recovery with no wound-healing issues and was pain free for the first 10 years. Although reporting no trauma or inciting event, she now describes pain in the entire knee that is most severe with her first few steps. She has begun to notice night pain and, more recently, constant swelling. What is the most appropriate work-up at this time?

Explanation

DISCUSSION:
An evaluation of the painful total knee must be supported by an understanding of the potential etiologies of pain. They may include, aseptic loosening, infection, osteolysis, gap imbalance, referred pain, stiffness, and complex regional pain syndrome. In this case, the patient demonstrates start-up pain and had no prior history of infections. Her radiographs show subsidence of the tibia, indicating a loose prosthesis. Knowing that the prosthesis is already loose precludes the need for a bone scan. It is, however, important to rule out infection in this case; therefore, CRP and ESR testing is essential. Aspiration is also recommended when going into knee arthroplasty, and infection is a concern.

Question 87

Which of the following is associated with the use of bisphosphonates in the setting of metastatic breast cancer to the spine?

Explanation

DISCUSSION: The indications of bisphosphonate therapy in breast cancer patients range from the correction of hypercalcemia to the prevention of cancer treatment-induced bone loss. Bisphosphonates reduce metastatic bone pain in at least 50% of patients and can reduce the frequency of skeletal-related events by 30% to 40%. Osteonecrosis of the jaw could occur in up to 2.5% of breast cancer patients during long-term bisphosphonate therapy.
REFERENCE: Body JJ: Breast cancer: Bisphosphonate therapy for metastatic bone disease. Clin Cancer Res 2006;12:6258s-6263s.

Question 88

The usual presentation of traumatic subscapularis tears is most often seen after forced

Explanation

DISCUSSION: The typical mechanism of injury is a fall and the patient grasps something to prevent the fall. This maneuver forces the arm into external rotation against resistance.
REFERENCES: Kreuz PC, Remiger A, Erggelet C, et al: Isolated and combined tears of the subscapularis tendon. Am J Sports Med 2005;33:1831-1837.
Gerber C, Hersche O, Farron A: Isolated rupture of the subscapularis tendon. J Bone Joint Surg Am 1996;78:1015-1023.

Question 89

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 90

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 91

A B C D E Figures 45a through 45c are the MR images of a 22-year-old woman who has had 6 months of ankle pain related to activities of daily living. She recently completed a course of cast immobilization and protected weight bearing without symptom resolution. Figures 45d and 45e are the intraoperative arthroscopy images after minimal probing. What is the most appropriate treatment?

Explanation

DISCUSSION
The MR images reveal a large cystic medial talar dome osteochondral lesion (OCL) in a patient who has failed nonsurgical treatment. Ankle fusion is inappropriate because the patient has an otherwise normal ankle. Arthroscopic debridement and drilling are appropriate for smaller (< 1.5 cm sq) noncystic lesions. Retrograde drilling and bone grafting is an option in the treatment of cystic OCL if the cartilage surface is intact; however, intraoperative arthroscopy images show that this patient's cartilage surface is unstable. Osteochondral allografts and autografts are effective in the treatment of large cystic talar dome OCLs but are not appropriate for the initial surgical treatment of smaller lesions like this one.
RECOMMENDED READINGS
Hannon CP, Smyth NA, Murawski CD, Savage-Elliott I, Deyer TW, Calder JD, Kennedy JG. Osteochondral lesions of the talus: aspects of current management. Bone Joint J. 2014 Feb;96-B(2):164-71. doi: 10.1302/0301-620X.96B2.31637. Review. PubMed PMID:

Question 92

A 29-year-old ultramarathoner, who is halfway into a 50-mile race, is sweating profusely. He suddenly collapses, is unresponsive, and has violent muscle contractions. Prior to these symptoms, he had been drinking water at every water stop (every 1 mile). What is the most likely diagnosis?

Explanation

DISCUSSION: Hyponatremia (“water intoxication”) can occur in endurance athletes such as ultramarathoners who are sweating profusely and drinking only water as fluid replacement. Sports drinks which contain electrolytes are a better replacement in this group of athletes. Sodium is the mineral most commonly affected by physical exercise. Sodium concentration in sweat depends on diet, hydration, and heat acclimation. In most cases, sodium lost in sweat can be replaced by regular diet. Potassium plays an important role in nerve conduction and muscle contraction but is not lost in excessive amounts in sweat during exercise. The most frequent loss of potassium is through gastrointestinal disorders or excessive loss from the kidneys. Rehrer reported that overhydrating during very long-lasting exercise in the heat with low or negligible sodium intake can result in reduced performance and hyponatremia. With hyponatremia, the serum sodium is abnormally low, resulting in brain swelling, seizures, coma, and potentially death. Interestingly, hyponatremia is rarely seen in adolescent athletes and young children.
REFERENCES: Griffin LY: Emergency preparedness: Things to consider before the game starts. J Bone Joint Surg Am 2005;87:894-902.
Rehrer NJ: Fluid and electrolyte balance in ultra-endurance sport. Sports Med 2001;31:701-715.

Question 93

A 21-year-old woman with Marfan syndrome is seeking evaluation of her scoliosis. She reports no back or leg pain, and the neurologic examination is normal. Lateral and bending radiographs are shown in Figures 7a through 7e. Management should consist of

Explanation

DISCUSSION: Because the patient’s thoracolumbar scoliosis is of a large enough magnitude, observation or bracing is not recommended. The thoracolumbar curve is flexible enough and L4 corrects well enough to the pelvis to consider anterior spinal fusion from T10 to L4.
REFERENCES: Garfin SR, Vaccaro AR (eds): Orthopaedic Knowledge Update: Spine. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1997, pp 161-171.
Turi M, Johnston CE II, Richards BS: Anterior correction of idiopathic scoliosis using TSRH instrumentation. Spine 1993;18:417-422.
Moskowitz A, Trommanhauser S: Surgical and clinical results of scoliosis surgery using Zielke instrumentation. Spine 1993;18:2444-2451.

Question 94

A 7-year-old girl with a known diagnosis of neurofibromatosis has neck pain and deformity. She has been wearing a soft cervical collar for the past 2 months with mild relief of her symptoms. An MRI scan shows several small neurofibromas on the left side of the cervical spine near the foramina at C6 and 7. A lateral cervical spine radiograph is shown in Figure 34. What is the most appropriate management?

Explanation

REFERENCES: Crawford AH, Schorry EK: Neurofibromatosis update. J Pediatr Orthop 2006;26:4I3- 423. MehJman CT, Al-Sayyad MJ, Crawford AH: Effectiveness of spinal release and halo-femoral traction in the management of severe spinal deformity. J Pediatr Orthop 2004;24:667-673.

Question 95

A 16-year-old high school football player who sustained an acute forceful dorsiflexion ankle injury reported that he felt a pop and then noted immediate swelling over the lateral malleolus. Examination 24 hours later reveals moderate swelling and tenderness along the lateral malleolus. The external rotation, squeeze, anterior drawer, and talar tilt tests are negative. Subluxation of the peroneal tendons is palpable over the peroneal groove of the fibula. Radiographs reveal a small cortical avulsion off the distal rim of the fibula. The stress views show no instability. Initial management for this injury should include

Explanation

DISCUSSION: The patient has an acute peroneal tendon dislocation. The evaluation for syndesmotic injury and lateral ankle instability is negative. The cortical avulsion off the distal tip of the lateral malleolus, a rim fracture, is characteristic of peroneal tendon dislocations. The sensation of apprehension or frank subluxation of the peroneal tendons with active dorsiflexion of the foot while the foot is held in plantar flexion confirms the diagnosis. Based on these findings, initial management should consist of cast immobilization and protected weight bearing. If a recurrent or chronic condition develops, surgery is the most reliable treatment option.
REFERENCES: Arrowsmith SR, Fleming LL, Allman FL: Traumatic dislocations of the peroneal tendons. Am J Sports Med 1983;11:142-146.
Marti R: Dislocation of the peroneal tendons. Am J Sports Med 1977;5:19-22.

Question 96

When comparing the overall outcomes of surgical versus nonsurgical treatment of stable thoracolumbar burst fractures in patients without neurologic injury, 5 years following injury, the principle differences lie in Review Topic

Explanation

When patients are compared at 5 years follow-up, there are no statistically significant differences between the two groups with respect to kyphosis, the degree of retropulsed bone resorption, pain and function levels, or the ability to return to work. Nonsurgical management of stable neurologically intact burst fractures has a very low incidence of complications.

Question 97

A 75-year-old patient returns for follow-up after undergoing bilateral total hip arthroplasty (THA). The right hip is a hybrid THA performed 12 years ago, whereas the left hip is a cementless THA performed 10 years ago. Both acetabular components are the same type, same size, and from the same manufacturer. Both femoral heads are 28-mm cobalt-chromium components. What is the most likely explanation for the advanced polyethylene wear in one hip?

Explanation

DISCUSSION: Over the past three decades, gamma irradiation and air has been the most common method of sterilizing polyethylene used in total joint arthroplasty. This method of sterilization results in breakage of the chemical bonds within the polymer. While this promotes cross-linking, it also leaves the polyethylene vulnerable to oxidation, especially if packaged in an air environment. Oxidation has been shown to decrease polyethylene’s molecular weight, ultimate tensile strength, elongation, and toughness which results in a stiffer, more brittle material that is less resistant to wear. Severity of oxidation and a decrease in mechanical properties have been shown to be related to the length of time that the component is exposed to air (the shelf life). Currier and associates studied the clinical performance of gamma irradiated in air polyethylene components that had been shelf aged. They demonstrated that for the first

5 years of shelf life, polyethylene oxidized rather slowly. However, polyethylene components with a shelf life of more than 5 years would be expected to have minimal mechanical toughness and would likely fail rapidly if implanted. Bohl and associates evaluated 135 patients who had undergone total knee arthroplasty. Survivorship at 5 years was 100% for components with a shelf life of less than 4 years, 89% for components with a shelf life of 4 to 8 years, and 79% for components with a shelf life of more than 8 years. Sychterz and associates reported no correlation between shelf life and true wear rates for components with a shelf life of less

than 3 years. In summary, both in vivo and in vitro data suggest that shelf life in excess of

3 to 5 years has a direct effect on wear of polyethylene.
REFERENCES: Currier BH, Currier JH, Collier JP, et al: Shelf life and in vivo duration: Impacts on performance of tibial bearings. Clin Orthop 1997;342:111-122.
Bohl JR, Bohl WR, Postak PD, et al: The Coventry Award: The effects of shelf life on clinical outcome for gamma sterilized polyethylene tibial components. Clin Orthop 1999;367:28-38.
Sychterz CJ, Young AM, Orishimo K, et al: The relationship between shelf life and in vivo wear for polyethylene acetabular liners. J Arthroplasty 2005;20:168-173.

Question 98

After performing a total hip arthroplasty through a posterolateral approach, an orthopaedic surgeon is unable to adequately externally rotate the leg and subsequently exposes the anterior capsule. When releasing the inferior aspect of the anterior capsule, pulsatile bleeding is encountered. A branch of which artery is most likely lacerated?

Explanation

DISCUSSION
Branches of the lateral femoral circumflex artery arise from the inferior aspect of the anterior hip capsule. They can be injured when removing the anterior capsule from any approach. The inferior gluteal artery supplies the gluteus maximus. The medial femoral circumflex artery enters the hip joint along the path of the obturator externus tendon. The femoral artery crosses the anterior hip joint in the superior-to-inferior direction and is located just medial to the hip joint.

Question 99

A 12-year-old boy falls from a bicycle. A radiograph of his injured shoulder is shown in Figure 41. What is the optimal method of treatment?

Explanation

DISCUSSION: The radiograph reveals a distal clavicle fracture. In children, a periosteal sleeve will remain attached to the intact coracoclavicular ligament, and as such, remodeling can be expected. Therefore, nonsurgical management with a sling is preferred. Surgical treatment is not necessary, and a shoulder spica cast offers no advantage over a simple sling.
REFERENCES: Bishop JY, Flatow EL: Pediatric shoulder trauma. Clin Orthop Relat Res 2005;432:41-48.

Question 100

A 59-year-old man reports moderate shoulder pain and very restricted range of motion after undergoing humeral arthroplasty for osteoarthritis 1 year ago. An AP radiograph is shown in Figure 32. Management should now consist of

Explanation

DISCUSSION: The radiograph reveals that an insufficient amount of the proximal humerus was excised in the index procedure, resulting in malalignment of the humeral component, overstuffing of the glenohumeral joint, and glenoid arthritis. It is unlikely that physical therapy or soft-tissue releases alone will be adequate. Revision of the humeral component, recutting of the proximal humerus to allow a more anatomic alignment of the humeral component, appropriate soft-tissue releases, and glenoid arthroplasty will offer the best chance of improvement in this difficult situation.
REFERENCES: Neer CS II, Kirby RM: Revision of humeral head and total shoulder arthroplasties. Clin Orthop 1982;170:189-195.
Petersen SA, Hawkins RJ: Revision of failed total shoulder arthroplasty. Orthop Clin North Am 1998;29:519-533.

Full Question & Answer Text (for Search Engines)

Question 1:

Which of the following is a contraindication to laminoplasty in a patient with cervical spondylotic myelopathy? Review Topic

Options:

Space available for the cord of less than 8 mm
Ossification of the posterior longitudinal ligament
Fixed cervical kyphosis
Previous posterior surgery
Concomitant cervical radiculopathy

Correct Answer: Fixed cervical kyphosis

Explanation:

Question 2:

Options:

hypokalemia.
administration of warfarin.
administration of antibiotics.
general anesthesia.
early mobilization and physical therapy.

Correct Answer: hypokalemia.

Explanation:

Question 3:

To prevent injury to the posterior interosseous nerve during the approach for reduction and fixation of a fracture of the radial head, anterior retraction should be performed with the forearm

Options:

Maximally pronated and elbow extended
Maximally pronated and the elbow flexed
Maximally supinated and the elbow flexed
Maximally supinated and the elbow extended
In neutral rotation, with the elbow extended

Correct Answer: Maximally pronated and the elbow flexed

Explanation:

Question 4:

From which artery does the princeps pollicis artery branch?

Options:

Dorsal radial carpal artery
Dorsal ulnar carpal artery
Ulnar artery
Radial artery

Correct Answer: Radial artery

Explanation:

DISCUSSION
The princeps pollicis artery can be located on the palmar aspect of the adductor pollicis and emerges into the subcutaneous tissue at the thumb metacarpophalangeal flexion crease. It branches from the radial artery just distal to the location of the deep palmar arch.
RECOMMENDED READINGS
Coleman SS, Anson B: Arterial patterns in the hand based on a study of 650 specimens. Surg Gynec Obstet 1961;4:409-424.
Ames EL, Bissonnette M, Acland R, Lister G, Firrell J. Arterial anatomy of the thumb.
78
J Hand Surg Br. 1993 Aug;18(4):427-36. PubMed PMID: 8409651.
View Abstract at
PubMed

Question 5:

Vertebral fractures are common in the thoracolumbar spine. What is the most important factor that determines the strength of the cancellous bone in the vertebral body?

Options:

Mineral content
Rate of loading
Anatomic level of the vertebra
Apparent density
Trabecular number

Correct Answer: Apparent density

Explanation:

Question 6:

What joint always remains uninvolved in all stages of scapholunate advanced collapse (SLAC) deformity of the wrist?

Options:

Distal radioscaphoid
Proximal radioscaphoid
Radiolunate
Scaphocapitate
Capitolunate

Correct Answer: Radiolunate

Explanation:

Question 7:

Options:

MRI
Doppler arterial study
Arteriography
Electromyography
Triple phase bone scan (technetium Tc 99m)

Correct Answer: Doppler arterial study

Explanation:

Question 8:

Based on the radiographic findings shown in Figure 41, which of the following wrist ligaments is most likely disrupted?

Options:

Short radiolunate
Long radiolunate
Scapholunate
Ulnolunate
Lunotriquetral

Correct Answer: Scapholunate

Explanation:

Question 9:

-What is the etiology of this patient’s problem?

Options:

Ischemia
Overuse condition
Pathologic laxity
Increased humeral retroversion

Correct Answer: Overuse condition

Explanation:

DISCUSSION FOR QUESTIONS 78 THROUGH 80
Little leaguer’s shoulder is an overuse condition of the proximal humeral physis. Patients report diffuse pain that is worse with throwing. Factors that contribute to the condition include excessive throwing,improper throwing mechanics, and muscle-tendon imbalance. Radiographs usually show widening of the proximal humeral physis, and, in more severe cases, metaphyseal demineralization or fragmentation. Surgical fixation is not required for healing. Treatment involves rest until symptoms resolve, followed by initiation of an interval throwing program. Pitching coaches should evaluate throwing mechanics and maintain pitch counts. The dominant shoulders of throwing athletes undergo adaptive changes, resulting in increased external rotation and decreased internal rotation. These changes occur secondary to softtissue and bony adaptations, including increased humeral retroversion. Ischemia has been implicated as a potential cause of osteochondritis dissecans lesions. Rotator cuff tendonitis presents with anterolateral shoulder pain that is worse with activity. Pain is reproduced with resisted supraspinatus testing, and radiograph findings are typically normal.
Adolescent shoulder injuries are often caused by subtle, atraumatic instability most often sustained in sports with overhead movements, including baseball. These symptoms are more likely to occur in athletes with evidence of increased soft-tissue laxity.

Question 10:

Options:

Anti-inflammatory medication and non-weightbearing for 6 weeks
Urgent CT scan
Hip arthroscopy
Open surgical repair
Dynamic stretching and progressive mobilization

Correct Answer: Urgent CT scan

Explanation:

Question 11:

Options:

a long leg cast for 6 weeks.
an ankle support and return to activities.
a short leg cast for 4 weeks.
open repair of ligaments and active range of motion.
open repair of ligaments and casting for 6 weeks.

Correct Answer: a short leg cast for 4 weeks.

Explanation:

Question 12:

Options:

Knee-ankle-foot orthosis with locking joints
Knee and ankle fusion
Soft-tissue release of the ankle and a locked knee orthosis
Soft-tissue release of the ankle and a knee-ankle-foot orthosis with a locked ankle and drop-lock knee joint
Ankle fusion and a knee-ankle-foot orthosis

Correct Answer: Soft-tissue release of the ankle and a knee-ankle-foot orthosis with a locked ankle and drop-lock knee joint

Explanation:

Question 13:

Options:

A well-placed and well-calibrated arterial line would be the most helpful clinical tool for determining when this patient is out of shock
The hematocrit well within normal limits means the patient is not in hemodynamic shock
A combination of heart rate greater than 120 and MAP less than 65 equates to poor tissue perfusion levels
Normal lactate levels and base excess are markers of adequate tissue perfusion
His orthopaedic injury alone cannot explain his vital sign derangements and an exploratory laparotomy is indicated

Correct Answer: A well-placed and well-calibrated arterial line would be the most helpful clinical tool for determining when this patient is out of shock

Explanation:

Question 14:

Options:

Callus decreases torsional stability and stiffness at the fracture site
Callus formation is random and unstructured and does not affect the local biomechanical properties
The callus decreases peak torque to failure with time
The callus increases the moment of inertia, resulting in less strain at the fracture site
The callus decreases the moment of inertia, increasing stress at the fracture site

Correct Answer: Callus decreases torsional stability and stiffness at the fracture site

Explanation:

Question 15:

Options:

Period of immobilization followed by physical therapy
Local corticosteroid injection
Surgical repair
Platelet-rich plasma (PRP)

Correct Answer: Surgical repair

Explanation:

Question 16:

..One week after closed reduction of a primary anterior shoulder dislocation, a 25-year-old athlete should be counseled that

Options:

recurrence rate is reduced with 4 weeks of immobilization instead of 2 weeks of immobilization.
age at the time of injury is the most consistent risk factor for recurrent instability.
a majority of patients in this age group will elect to have surgery for recurrent instability.
after an in-season return to sports, his likelihood of choosing surgery after the season is 25%. DISCUSSION.. In a study by Sachs and associates, age younger than 25 years at the time of presentation was found to be the strongest predictor of recurrent instability. In this age group (20-to 29-year-olds), only 14% elected to proceed with surgery. After an in-season return to sports, about 50% of patients in this same study chose to proceed with surgery after completing the season. Immobilization in a sling for longer than 2 weeks has no effect on future instability.

Correct Answer: age at the time of injury is the most consistent risk factor for recurrent instability.

Explanation:

Question 17:

Options:

a custom tibial implant.
a hinged prosthesis.
reconstruction with structural allograft.
reconstruction with iliac crest bone graft.
filling the defect with cement.

Correct Answer: reconstruction with structural allograft.

Explanation:

Question 18:

The spinal cord terminates as the conus medullaris at what vertebral level in adults? Review Topic 1 T12

Options:

Correct Answer: L2

Explanation:

The spinal cord anatomy changes at the thoracolumbar junction. The spinal cord terminates as the conus medullaris at the lower portion of L1 in women and the pedicle of L1 in men.

Question 19:

Options:

Anterior glenoid rim fracture tear
Anterior inferior labral tear
Posterior labral tear
Total capsular laxity
Osteochondral defect of the humeral head

Correct Answer: Posterior labral tear

Explanation:

Question 20:

Options:

closed reduction and cast immobilization.
open reduction and internal fixation (ORIF).
arthrodesis.
resection arthroplasty.

Correct Answer: open reduction and internal fixation (ORIF).

Explanation:

Question 21:

Options:

Posterior tibial tendinitis
Osteoid osteoma
Posterior ankle impingement
Tibial stress fracture
Flexor hallucis longus tendinitis

Correct Answer: Tibial stress fracture

Explanation:

Question 22:

Which of the following statements regarding conus medullaris syndrome is most accurate?

Options:

Conus medullaris syndrome most commonly accompanies injuries at the T12-L2 region.
Conus medullaris injury is a lower motor neuron injury, resulting in an excellent prognosis for recovery of bowel and bladder dysfunction.
The conus medullaris houses the motor cell bodies for the lumbar roots.
Lower extremity weakness is a common sign of conus medullaris syndrome.
Autonomic dysreflexia is common.

Correct Answer: Conus medullaris syndrome most commonly accompanies injuries at the T12-L2 region.

Explanation:

DISCUSSION: Conus medullaris syndrome most frequently occurs as a result of trauma or with a disk herniation at L1, resulting in a lower motor neuron syndrome but with a poor prognosis for recovery of bowel and bladder dysfunction. The conus region, as the termination of the spinal cord, contains the motor cell bodies of the sacral roots. The syndrome is usually a sacral level neural injury; therefore, lower extremity weakness is uncommon.
REFERENCES: Haher TR, Felmly WT, O’Brien M: Thoracic and lumbar fractures: Diagnosis and management, in Bridwell KH, Dewald RL, Hammerberg KW, et al (eds): The Textbook of Spinal Surgery, ed 2. New York, NY, Lippincott Williams & Wilkins, 1977, pp 1773-1778.
Reitman
CA
(ed): Management of Thoracolumbar Fractures. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2004, pp 35-45.

Question 23:

A complication unique to computer navigation of total knee arthroplasty (TKA) is

Options:

femoral shaft fracture.
intercondylar femur fracture.
ligament disruption.
nerve palsy.

Correct Answer: femoral shaft fracture.

Explanation:

DISCUSSION
Threaded pins are frequently inserted into the femoral shaft and tibial shafts or proximal tibia to attach arrays for tracking devices. There have been case reports of fractures propagating through the pin tracks, which is a complication unique to computer navigation. Intercondylar fractures can occur following posterior stabilized TKA. Vascular injury, ligament disruption, and nerve palsy are rare complications following TKA performed with or without computer navigation.
CLINICAL SITUATION FOR QUESTIONS 111 THROUGH 113
Figure 111 is the anteroposterior radiograph of a 79-year-old woman with a presurgical diagnosis of osteonecrosis who sustained a periprosthetic tibia fracture following her total knee arthroplasty (TKA).

Question 24:

Options:

First metatarsophalangeal arthrodesis
Distal chevron osteotomy and bunionectomy with closing wedge osteotomy and soft-tissue release
Bunionectomy with proximal metatarsal osteotomy
Bunionectomy with first metatarsal cuneiform fusion
Bunionectomy with proximal phalanx osteotomy and distal chevron osteotomy

Correct Answer: First metatarsophalangeal arthrodesis

Explanation:

DISCUSSION: Arthrodesis is indicated for severe bunion and hallux valgus deformities, but particularly with extensive degenerative disease of the first metatarsophalangeal joint. The other bunionectomy procedures have different indications, none of which include symptomatic first metatarsophalangeal degenerative disease.
REFERENCES: Richardson EG (ed): Orthopaedic Knowledge Update: Foot and Ankle 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2004, pp 3-15.
Tourne Y, Saragaglia D, Zattara A, et al: Hallux valgus in the elderly: Metatarsophalangeal arthrodesis of the first ray. Foot Ankle Int 1997;18:195-198.

Question 25:

Which of the following forms of nonsurgical management is considered best for acute low back pain without radiculopathy?

Options:

Acupuncture
Epidural steroid injections
Facet joint injections
Sclerosant injections
Bed rest

Correct Answer: Bed rest

Explanation:

Question 26:

Which gene mutation or polymorphism has been shown to most increase the risk for venous thromboembolic disease after elective total joint arthroplasty?

Options:

Factor V Leiden
Prothrombin G20210A
MTHFR/C677T/TT
Lupus anticoagulant

Correct Answer: MTHFR/C677T/TT

Explanation:

Question 27:

Denosumab, a monoclonal antibody used to treat osteoporosis, works through inhibition of

Options:

receptor activator of nuclear factor kappa beta (RANK).
RANK ligand (RANKL).
osteoprotegrin (OPG).
tumor necrosis factor (TNF).

Correct Answer: RANK ligand (RANKL).

Explanation:

Question 28:

Which of the following is true regarding plating of humeral shaft fractures compared to intramedullary nailing?

Options:

worse functional results
higher need for subsequent surgeries
less blood loss
higher union rates
increased postoperative shoulder stiffness

Correct Answer: worse functional results

Explanation:

Question 29:

A sagittal T1-weighted MRI scan of the knee joint is shown in Figure 23. What structure is identified by the arrow?

Options:

Popliteal tendon
Ligament of Humphrey
Anterior cruciate ligament
Posterior cruciate ligament
Lateral gastrocnemius tendon

Correct Answer: Posterior cruciate ligament

Explanation:

Question 30:

..Figure 93 is the radiograph of a 72-year-old woman. Treatment includes fixation of the ulna. What options are recommended for the radius?

Options:

Radial head replacement to restore radiocapitellar contact
Radial head excision because there is no risk for posterolateral instability
Percutaneous fixation to avoid the risk for stiffness after surgery
Allograft reconstruction to prevent capitellar erosion DISCUSSION.. Prosthetic replacement is an appropriate option in cases of a nonreconstructable fracture to restore the radiocapitellar contact. Most complex fractures are associated with instability; therefore, it is advisable to consider open reduction and internal fixation or radial head replacement when the injury involves a dislocation or fracture of the ulna. Simple radial head excision may be a viable option for a comminuted fracture without instability or associated ulnar fracture. When the radial head is replaced, caution must be exercised to avoid overstuffing the joint because this can lead to stiffness from impingement, capitellar erosion, loss of flexion, or synovitis.

Correct Answer: Radial head replacement to restore radiocapitellar contact

Explanation:

CLINICAL SITUATION FOR QUESTIONS 94 THROUGH 96
Figure 94 is the anteroposterior radiograph of a 75-year-old woman who has a 5-year history of progressive pain, crepitus, and loss of motion in her shoulder. She had a rotator cuff repair 10 years ago. Examination reveals 60 degrees of active forward elevation and 20 degrees of external rotation with her arm at her side. Passively she can be brought to 160 degrees of forward elevation and 90 degrees of external rotation with her arm at her side. A glenohumeral joint injection with local anesthetic eliminated pain, but there is no observed change in active motion.

Question 31:

What is the most common physical finding in a patient with femoroacetabular impingement (FAI)? Review Topic

Options:

Increased external rotation
Increased abduction
Decreased external rotation
Decreased flexion and internal rotation
Decreased adduction

Correct Answer: Decreased flexion and internal rotation

Explanation:

Question 32:

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 33:

Options:

Osteonecrosis
Transient osteoporosis
Loose chondral fragment
Labral tear
Femoral neck stress fracture

Correct Answer: Labral tear

Explanation:

DISCUSSION: The MRI arthrogram reveals dye extravasation into the labrum, consistent with a labral tear. The MRI findings are not typical of osteonecrosis, stress fracture, or transient osteoporosis. There is no increase in bone marrow edema in the neck or femoral head.
REFERENCES: Guanche CA, Sikka RS: Acetabular labral tears with underlying chondralmalacia: A possible association with high-level running. Arthroscopy 2005;21:580-585.
McCarthy JC: The diagnosis and treatment of labral and chondral injuries. Instr Course Lect 2004;53:573-577.

Question 34:

Options:

wide resection and radiation therapy.
wide resection and chemotherapy.
below-knee amputation.
observation.
radiation therapy.

Correct Answer: below-knee amputation.

Explanation:

Question 35:

Which of the following positions of immobilization has been shown to best approximate the anterior labrum against the glenoid rim following anterior dislocation of the shoulder?

Options:

Abduction and external rotation
Abduction and internal rotation
Adduction and external rotation
Adduction and internal rotation
Extension

Correct Answer: Adduction and external rotation

Explanation:

Question 36:

Options:

Posterior talofibular ligament
Distal tibiofibular syndesmosis
Anterior talofibular ligament
Deltoid ligament
Calcaneofibular ligament

Correct Answer: Deltoid ligament

Explanation:

DISCUSSION: In the presence of a supination external rotation-type fracture of the distal fibula (Weber type B), stability of the ankle is best assessed by performing an external rotation stress AP view of the ankle. This test is used to assess the integrity of the deltoid ligament. The presence of a deltoid ligament rupture results in instability and generally is best managed surgically. The gravity stress test can also be used.
REFERENCES: Egol KA, Amirtharajah M, Tejwani NC, et al: Ankle stress test for predicting the need for surgical fixation of isolated fibular fractures. J Bone Joint Surg Am 2004;86:2393-2398.
McConnell T, Creevy W, Tornetta P III: Stress examination of supination external rotation-type fibular fractures. J Bone Joint Surg Am 2004;86:2171-2178.
Schock HJ, Pinzur M, Manion L, et al: The use of the gravity or manual-stress radiographs in the assessment of supination-external rotation fractures of the ankle. J Bone Joint Surg Br 2007;89:1055-1059.

Question 37:

What complication is frequently associated with the Weil lesser metatarsal osteotomy (distal, oblique) in the treatment of claw toe deformities?

Options:

Floating toe
Nonunion
Osteonecrosis
Inadequate shortening
Dorsal displacement

Correct Answer: Floating toe

Explanation:

DISCUSSION: Weil osteotomies are useful in achieving shortening of a lesser metatarsal with preservation of the distal articular surface. The osteotomy is oriented from distal-dorsal to proximal-plantar; therefore, proximal displacement of the distal fragment is associated with plantar (not dorsal) displacement as well. Plantar displacement can result in the intrinsics acting dorsal to the center of the metatarsophalangeal joint and the development of an extended or “floating toe.” Nonunion, osteonecrosis, and inadequate shortening are infrequent complications associated with the Weil lesser metatarsal osteotomy.
REFERENCES: Trnka HJ, Nyska M, Parks BG, et al: Dorsiflexion contracture after the Weil osteotomy: Results of cadaver study and three-dimensional analysis. Foot Ankle Int
2001;22:47-50.
Trnka HJ, Muhlbauer M, Zettl R, et al: Comparison of the results of the Weil and Helal osteotomies for the treatment of metatarsalgia secondary to dislocation of the lesser metatarsophalangeal joints. Foot Ankle Int 1999;20:72-79.

Question 38:

Options:

Tenderness over the anterior talofibular and calcaneofibular ligaments
A positive dorsiflexion external rotation test
Loss of passive range of motion
Positive squeeze test
Inability to single leg hop

Correct Answer: Inability to single leg hop

Explanation:

Question 39:

What is the most important consideration in the preoperative evaluation of a child with polyarticular or systemic juvenile rheumatoid arthritis (JRA)?

Options:

Cervical spine assessment
Temporomandibular joint (TMJ)/jaw assessment
Dental assessment
Stress dosing with corticosteroids
Opthalmology examination

Correct Answer: Cervical spine assessment

Explanation:

Question 40:

In long-term follow-up studies of cemented total knee arthroplasty (TKA), the lowest rates of osteolysis have been associated with which design feature?

Options:

Metal-backed patellar components
Modular cruciate-retaining tibial inserts
Modular cruciate-substituting tibial inserts
Monolithic tibial trays

Correct Answer: Monolithic tibial trays

Explanation:

Question 41:

Options:

repetitive loading and fatigue failure.
incomplete bone ingrowth with focal osteolysis.
rotational bone axial loading.
a fixed component with a modulus mismatch.
use of titanium instead of cobalt-chromium.

Correct Answer: a fixed component with a modulus mismatch.

Explanation:

Question 42:

Options:

MRI scan of the knee
CT scan of the distal femur
Application of a long-leg cast
Arteriogram of the extremity
Reduction and fixation of the fracture

Correct Answer: Reduction and fixation of the fracture

Explanation:

Question 43:

Options:

Osteoarthritis
Rheumatoid arthritis
Medial meniscal tear
Osteonecrosis
Transient osteoporosis

Correct Answer: Osteonecrosis

Explanation:

Question 44:

Options:

Penicillin G
Cefazolin sodium
Oxacillin
Ampicillin sodium/sulbactam sodium
Gentamicin

Correct Answer: Ampicillin sodium/sulbactam sodium

Explanation:

Question 45:

Options:

The patient is at risk for repeated episodes of ischemic necrosis.
The patient is at high risk for deep venous thrombosis.
No further problems will develop on the involved side.
Accelerated onset of degenerative arthritis will develop on the involved side in the fifth or sixth decade of life.
Epiphyseodesis will be required on the involved side.

Correct Answer: Accelerated onset of degenerative arthritis will develop on the involved side in the fifth or sixth decade of life.

Explanation:

Question 46:

What is the prognosis for ambulation, from best to worst, for patients with an incomplete spinal cord injury?

Options:

Central cord syndrome, anterior cord syndrome, Brown-Sequard syndrome
Central cord syndrome, Brown-Sequard syndrome, anterior cord syndrome
Brown-Sequard syndrome, anterior cord syndrome, central cord syndrome
Brown-Sequard syndrome, central cord syndrome, anterior cord syndrome
Anterior cord syndrome, central cord syndrome, Brown-Sequard syndrome

Correct Answer: Brown-Sequard syndrome, central cord syndrome, anterior cord syndrome

Explanation:

Question 47:

Emergent management of acute tooth displacement (luxation) includes

Options:

delaying replantation until a dentist is present.
scrubbing the root of the tooth clean with hydrogen peroxide.
transporting the tooth in a carbonated beverage.
emergency root canal. §. immediate repositioning or replantation of the tooth.

Correct Answer: delaying replantation until a dentist is present.

Explanation:

Question 48:

Options:

L4 nerve root injury during laminectomy
L5 nerve root injury during laminectomy
Patient positioning during surgery
Dural tear
Use of monoaxial pedicle screws

Correct Answer: L4 nerve root injury during laminectomy

Explanation:

Question 49:

Options:

Administration of broad spectrum IV antibiotics
Irrigation and debridement in OR followed by broad spectrum IV antibiotics
NSAIDS and observation with repeat ESR and CRP in 24 hours
Joint aspiration and blood cultures

Correct Answer: Joint aspiration and blood cultures

Explanation:

Question 50:

What preoperative factor correlates best with the outcome of rotator cuff repair?

Options:

Size of the tear
Age of the patient
Arm dominance
Rupture of the long head of the biceps
Preoperative pain score

Correct Answer: Size of the tear

Explanation:

Question 51:

Porous hydroxyapatite is placed into a bone defect. Incorporation of this bone graft substitute is expected to follow which of the following patterns?

Options:

Neovascularization and appositional new bone growth
Creeping substitution
Inflammatory response with sequestration
Dissolution of the graft material and osteoblastic bone formation
Bridging bone formation without incorporation of the graft

Correct Answer: Neovascularization and appositional new bone growth

Explanation:

Question 52:

Which of the following situations is most likely to decrease sentinel event errors?

Options:

Physician and nurse training is lengthened by 20%
Resident hours are decreased to 55 hours per week
An environment is created where all members of the healthcare team feel empowered to express their concerns and beliefs
Holding individuals responsible for errors in clinical judgement
Physicians and nurses are assigned to a smaller number of patients

Correct Answer: Physician and nurse training is lengthened by 20%

Explanation:

Question 53:

Figure 24 shows the radiograph of a 47-year-old woman who has severe right hip pain and a limp. Management should consist of

Options:

acetabular osteotomy.
femoral and acetabular osteotomy.
total hip arthroplasty using standard trochanter osteotomy and cementless components.
total hip arthroplasty using femoral shortening osteotomy and cementless components.
total hip arthroplasty using femoral shortening osteotomy, a cemented socket, and a cementless femoral component.

Correct Answer: total hip arthroplasty using femoral shortening osteotomy and cementless components.

Explanation:

Question 54:

Options:

Sympathetic stellate block
Emergent fasciotomy
Emergent arterial thrombectomy
Venous duplex ultrasound studies
Arteriography

Correct Answer: Venous duplex ultrasound studies

Explanation:

Question 55:

What is the most appropriate treatment?

Options:

Arthroscopic washout
CT scan
Observation
Aspiration

Correct Answer: Observation

Explanation:

Question 56:

Options:

shoulder exercises, mild analgesics, and activity modification.
transfer of the latissimus dorsi to the greater tuberosity.
arthroscopy and debridement of the tendon edges.
arthroscopy, arthroscopic acromioplasty, coracoacromial ligament release, and mini open repair.
arthroscopy, arthrotomy, acromioplasty, and primary repair of the rotator cuff.

Correct Answer: shoulder exercises, mild analgesics, and activity modification.

Explanation:

Question 57:

Options:

Hardware migration is more likely than with acromioclavicular pinning.
Failure of fixation is usually at the level of the clavicle.
Hardware removal is avoided to prevent late displacement.
Neurologic injury most likely involves the axilllary nerve.
Acromioclavicular arthritis is more likely than with nonsurgical management.

Correct Answer: Acromioclavicular arthritis is more likely than with nonsurgical management.

Explanation:

Question 58:

When using the direct lateral (or Hardinge) approach for hip arthroplasty, three muscles are detached from the femur. In addition to the vastus lateralis, they include the

Options:

iliopsoas and sartorius.
piriformis and obturator internus.
gluteus maximus and tensor fascia lata.
gluteus minimus and rectus femoris.
gluteus medius and gluteus minimus.

Correct Answer: gluteus medius and gluteus minimus.

Explanation:

DISCUSSION: This approach is criticized for the episodic limp associated with the muscle detachment and reattachment. Classically, two thirds of the gluteus medius is detached as a sleeve with the vastus lateralis. This exposes the gluteus minimus and the ligament of Bigelow. These must also be detached to allow dislocation of the hip and osteotomy of the femoral neck. The rectus femoris lies medially and anteriorly and does not need to be addressed. The piriformis and obturator internus are exposed during the posterior approach. Neither the gluteus maximus nor tensor fascia lata attach to the anterior femur. The sartorius and iliopsoas are not exposed during this dissection.
REFERENCES: Hoppenfeld S, deBoer P (eds): Surgical Exposures in Orthopaedics: The Anatomic Approach. Philadelphia, PA, JB Lippincott, 1984, pp 333-335.
Hardinge K: The direct lateral approach to the hip. J Bone Joint Surg Br 1982;64:17-19.

Question 59:

Figure 56 is the radiograph of an otherwise healthy 3-year-old boy who fell and sustained the isolated injury shown. What is the best treatment modality?

Options:

Elastic intramedullary nailing
Submuscular plating
Early hip spica casting
Traction as definitive treatment

Correct Answer: Early hip spica casting

Explanation:

Question 60:

Glenohumeral inferior stability in the adducted shoulder position is primarily a function of the

Options:

rotator cuff.
posterior glenohumeral ligament.
long head of the biceps tendon.
inferior glenohumeral ligament complex.
superior glenohumeral ligament.

Correct Answer: superior glenohumeral ligament.

Explanation:

Question 61:

Options:

It is contraindicated in patients with shoulder pseudoparalysis
It can be used in patients with deltoid dysfunction when combined with latissimus dorsi transfer
It shifts the center of rotation of the shoulder superior and lateral
The risk of scapular notching is increased with inferior placement of the glenoid component
The risk of instability is increased with an irreparable subscapularis

Correct Answer: It is contraindicated in patients with shoulder pseudoparalysis

Explanation:

Question 62:

What role does quorum sensing play in the development of a bacterial biofilm?

Options:

Activates genes that produce virulence factors
Creates planktonic bacteria
Facilitates bacterial adhesion to a substrate
Lowers antimicrobial resistance

Correct Answer: Activates genes that produce virulence factors

Explanation:

Question 63:

Options:

observation.
closed reduction and cast immobilization.
bilateral medial open reduction of the hips.
anterior open reduction with femoral shortening.
valgus osteotomy.

Correct Answer: observation.

Explanation:

Question 64:

Options:

A Vancouver type B1 fracture
Residual leg-length discrepancy
Loosening and subsidence of the femoral stem into anteversion
Loosening and subsidence of the femoral stem into retroversion

Correct Answer: Loosening and subsidence of the femoral stem into retroversion

Explanation:

Question 65:

Options:

hospital admission for IV antibiotics and observation.
an epidural steroid.
anterior diskectomy and fusion with autologous bone graft.
laminectomy for decompression and debridement.
laminectomy for decompression with an instrumented posterolateral fusion.

Correct Answer: laminectomy for decompression and debridement.

Explanation:

Question 66:

Options:

Infection
Patellar instability
Aseptic loosening
Progression of tibiofemoral arthritis

Correct Answer: Progression of tibiofemoral arthritis

Explanation:

Question 67:

Reverse total shoulder arthroplasty improves kinematics in the rotator cuff deficient joint by what directional change to the center of rotation? Review Topic

Options:

Medial
Lateral
Posterior
Proximal

Correct Answer: Medial

Explanation:

Question 68:

- Figure 67 shows the AP radiograph of both knees of a 26-year-old woman. A review of the patient’s medical record will most likely reveal a history of

Options:

Trauma
Hemophilia
Reiter’s syndrome
Rheumatoid arthritis
Systemic lupus erythematosus

Correct Answer: Systemic lupus erythematosus

Explanation:

Question 69:

Options:

Observation as the deformity should resolve in time
Wearing of straight last shoes
Serial stretching and casting for the next 6 to 12 weeks
Heyman, Herndon, and Strong capsular release at the tarsometatarsal and intermetatarsal joints
Berman and Gartland dome-shaped osteotomies of the metatarsal bases

Correct Answer: Serial stretching and casting for the next 6 to 12 weeks

Explanation:

DISCUSSION: Weinstein reported on 31 patients (45 feet) with congenital metatarsus adductus followed for an average of 33 years. Twenty-nine feet had moderate to severe deformities treated with manipulation and casting with a 90% success rate. In a young child, surgery is not indicated until nonsurgical management has failed. In patients 2 to 4 years of age, tarsometatarsal capsulotomies are indicated, whereas multiple metatarsal osteotomies are reserved for recalcitrant deformities in children older than 4 years of age. Mild or moderate metatarsus adductus that is passively correctable will resolve without treatment.
REFERENCES: Beaty J: Congenital anomalies of the lower extremity, in Canale ST (ed): Campbell’s Operative Orthopaedics, ed 10. Philadelphia PA, Mosby, 2003, pp 983-988.
Katz K, David R, Soudry M: Below-knee plaster cast for the treatment of metatarsus adductus.
J Pediatr Orthop 1999;19:49-50.
Weinstein SL: Bristol-Myers Squibb/Zimmer award for distinguished achievement in orthopaedic research. Long-term follow-up of pediatric orthopaedic conditions: Natural history and outcomes
of treatment. J Bone Joint Surg Am 2000;82:980-990.

Question 70:

- What is the primary mechanism of wear of polyethylene acetabular components?

Options:

Crevice corrosion
Oscillatory fretting
Oxidative degradation
Adhesion and abrasion
Fatigue and delamination

Correct Answer: Adhesion and abrasion

Explanation:

Question 71:

Which of the following patients requires preoperative noninvasive cardiac testing?

Options:

year-old man scheduled to undergo elective lumbar decompression and fusion, with a history of hypercholesteremia, hypertension, and deep venous thrombosis following treatment of an ankle fracture
year-old woman scheduled to undergo total knee arthroplasty, with a history of myocardial infarction, cerebrovascular accident, and diabetes mellitus
year-old woman scheduled to undergo total hip arthroplasty for osteonecrosis, no known medical comorbidities, but has not seen a physician in more than 20 years and drinks 7 to 10 alcoholic beverages per week
year-old man with an intertrochanteric hip fracture, with a history of chronic renal failure, colon
cancer, and obesity
year-old man with a fracture of the proximal femur, history of myocardial infarction, prostate adenocarcinoma, and hypothyroidism, and prior to the fracture he was able to climb a flight of stairs

Correct Answer: year-old woman scheduled to undergo total knee arthroplasty, with a history of myocardial infarction, cerebrovascular accident, and diabetes mellitus

Explanation:

Question 72:

Options:

Immediately
When skin wrinkles are present and abrasions are epithelialized
Five days after injury
Following analysis of laser Doppler skin measurements
Following measurement of transcutaneous oxygen tension

Correct Answer: When skin wrinkles are present and abrasions are epithelialized

Explanation:

Question 73:

Options:

observation.
a rigid collar for 6 weeks.
halo vest application.
open reduction and posterior stabilization.
open reduction, diskectomy, grafting, and anterior plate stabilization.

Correct Answer: a rigid collar for 6 weeks.

Explanation:

Question 74:

Options:

Unreduced posterior sternoclavicular dislocation
Congenital hypoplasia of the medial clavicle
Postmenopausal arthritis of the sternoclavicular joint
Sternoclavicular hyperostosis
Spontaneous subluxation of the right sternoclavicular joint

Correct Answer: Spontaneous subluxation of the right sternoclavicular joint

Explanation:

DISCUSSION: Spontaneous subluxation of the sternoclavicular joint occurs without any significant trauma. It is usually accentuated by placing the extremity in an overhead position. Discomfort usually resolves within 4 to 6 weeks with nonsurgical management.
REFERENCES: Rockwood CA, Wirth MA: Disorders of the sternoclavicular joint, in Rockwood CA, Matsen FA, Wirth MA, et al (eds): The Shoulder. Philadelphia, PA,
WB Saunders, 2004, vol 2, pp 1078-1079.
Rockwood CA, Odor JM: Spontaneous atraumatic anterior subluxation of the sternoclavicular joint. J Bone Joint Surg Am 1989;71:1280-1288.

Question 75:

Persistent symptoms and decreased function following distal clavicle resection, coracoacromial ligament transfer, and augmentation (modified Weaver-Dunn) are most likely related to Review Topic

Options:

anterior-posterior translation.
superior-inferior translation. 3inadequate resection of the distal clavicle.
excessive reduction of the clavicle relative to the coracoid.
unrecognized instability of the sternoclavicular joint.

Correct Answer: anterior-posterior translation.

Explanation:

Question 76:

The incidence of ipsilateral phrenic nerve blockade after an interscalene block approaches

Options:

15%.
25%.
50%.
75%.
100%.

Correct Answer: 100%.

Explanation:

Question 77:

Progressive paralysis is most likely to be seen in association with what type of congenital vertebral abnormality?

Options:

Anterior failure of formation
Anterior failure of segmentation
Posterior failure of formation
Posterior failure of segmentation
Lateral failure of segmentation

Correct Answer: Anterior failure of formation

Explanation:

Question 78:

The diagnosis of an infection after total knee arthroplasty is most reliably proven based on what single study?

Options:

Leukocyte count and C-reactive protein
Radiographs
Technetium Tc 99m and gallium bone scans
Aspiration of joint fluid
MRI

Correct Answer: Aspiration of joint fluid

Explanation:

DISCUSSION: In a study of 52 patients with infected total knee arthroplasties, Windsor and associates showed that the average leukocyte count was 8,300/mm
3
and that aspirated knee fluid was positive in all patients except one. Knee radiographs can be unclear in showing infection, which may be present without radiographic signs of loosening. Technetium Tc 99m and gallium bone scans may not conclusively show the presence of infection, particularly in the first 3 years after knee arthroplasty.
REFERENCES: Windsor RE, Bono JV: Infected total knee replacements. J Am Acad Orthop Surg 1994;2:44-53.
Windsor RE, Insall JN, Urs WK, et al: Two-stage reimplantation for the salvage of total knee arthroplasty complicated by infection: Further follow-up and refinement of indications. J Bone Joint Surg Am 1990;72:272-278.

Question 79:

Options:

Skeletal survey
PET scan
Indium-labeled WBC scan
Bone marrow aspiration and biopsy
Mammography

Correct Answer: Bone marrow aspiration and biopsy

Explanation:

Question 80:

Options:

Long-arm cast
Percutaneous screw fixation
Open reduction and internal fixation (ORIF) with bone graft
Proximal row carpectomy

Correct Answer: Open reduction and internal fixation (ORIF) with bone graft

Explanation:

Question 81:

A 73-year-old man sustains the fracture shown in Figure 62. Which of the following factors or combination of factors puts this patient at highest risk for nonunion if nonsurgical management is used?

Options:

Advanced age and shortening
Fracture displacement and rotation
Mid diaphyseal fracture
Male gender
Fracture comminution, fracture displacement, and advanced age

Correct Answer: Fracture comminution, fracture displacement, and advanced age

Explanation:

Question 82:

Options:

Immediately
In the second half
In 1 week
In 4 weeks
Next season

Correct Answer: Next season

Explanation:

Question 83:

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 84:

Options:

Open biopsy followed by curettage and bone grafting
MRI, whole-body bone scan, CT of the chest, followed by incisional biopsy
Allow the fracture to heal with nonsurgical management and serial radiographs
Open biopsy followed by wide resection and reconstruction with osteoarticular allograft
Open biopsy followed by wide resection and endoprosthetic replacement

Correct Answer: Allow the fracture to heal with nonsurgical management and serial radiographs

Explanation:

DISCUSSION: This radiolucent lesion with a “fallen leaf sign” is typical for a unicameral bone cyst(UBC). The most appropriate treatment is to allow the fracture to heal with clinical and radiographic observation. Curettage and bone grafting is not the best initial management for UBC. Wide resection is not indicated for UBC. The proximal humerus is the most common site for UBC. While staging studies consisting of MRI, bone scan, and CT of the chest are appropriate for lesions suspected of being malignant, the classical appearance of this UBC is such that this work-up is not necessary initially. Following fracture healing, aspiration and injection of the cyst may be indicated.
REFERENCES: Dormans JP, Pill SG: Fractures through bone cysts: Unicameral bone cysts, aneurysmal bone cysts, fibrous cortical defects, and nonossifying fibromas. Instr Course Lect 2002;51:457-467.
Deyoe L, Woodbury DF: Unicameral bone cyst with fracture. Orthopedics 1985;8:529-531.

Question 85:

Options:

Allograft reconstruction with semitendinosis weave to the humerus
Latissimus dorsi tendon transfer
Electrical stimulation
Shoulder arthrodesis
Arthroscopic pectoralis major tendon repair

Correct Answer: Allograft reconstruction with semitendinosis weave to the humerus

Explanation:

Question 86:

Options:

Knee aspiration with cell count/cultures, C-reactive protein (CRP) level, erythrocyte sedimentation rate (ESR), CT
Knee aspiration with cell count/cultures, CRP, ESR
Fresh-frozen specimen at the time of revision knee arthroplasty only
Technetium-99m bone scan, knee aspiration with cell count/cultures

Correct Answer: Knee aspiration with cell count/cultures, CRP, ESR

Explanation:

Question 87:

Which of the following is associated with the use of bisphosphonates in the setting of metastatic breast cancer to the spine?

Options:

Reduction in skeletal-related events by 30% to 40%
Jaw osteonecrosis in 15% of patients
Pain improvement in only 30% of patients
Improvement in serum hypocalcemia in 40% of patients
Accelerated bone destruction in 10% of patients

Correct Answer: Reduction in skeletal-related events by 30% to 40%

Explanation:

DISCUSSION: The indications of bisphosphonate therapy in breast cancer patients range from the correction of hypercalcemia to the prevention of cancer treatment-induced bone loss. Bisphosphonates reduce metastatic bone pain in at least 50% of patients and can reduce the frequency of skeletal-related events by 30% to 40%. Osteonecrosis of the jaw could occur in up to 2.5% of breast cancer patients during long-term bisphosphonate therapy.
REFERENCE: Body JJ: Breast cancer: Bisphosphonate therapy for metastatic bone disease. Clin Cancer Res 2006;12:6258s-6263s.

Question 88:

The usual presentation of traumatic subscapularis tears is most often seen after forced

Options:

internal rotation.
external rotation.
extension.
abduction.
forward flexion.

Correct Answer: external rotation.

Explanation:

DISCUSSION: The typical mechanism of injury is a fall and the patient grasps something to prevent the fall. This maneuver forces the arm into external rotation against resistance.
REFERENCES: Kreuz PC, Remiger A, Erggelet C, et al: Isolated and combined tears of the subscapularis tendon. Am J Sports Med 2005;33:1831-1837.
Gerber C, Hersche O, Farron A: Isolated rupture of the subscapularis tendon. J Bone Joint Surg Am 1996;78:1015-1023.

Question 89:

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 90:

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 91:

Options:

Ankle fusion
Arthroscopic debridement and drilling
Retrograde drilling and bone grafting
Malleolar osteotomy and osteochondral grafting

Correct Answer: Malleolar osteotomy and osteochondral grafting

Explanation:

Question 92:

Options:

Hypernatremia
Hyponatremia
Hyperkalemia
Hypokalemia
Hyperuremia

Correct Answer: Hyponatremia

Explanation:

Question 93:

Options:

observation and regular follow-up.
a custom-molded thoracolumbar orthosis.
anterior spinal fusion from T10 to L4.
anterior and posterior spinal fusion from T10 to L4.
posterior spinal fusion from T4 to L4.

Correct Answer: anterior spinal fusion from T10 to L4.

Explanation:

Question 94:

Options:

Anterior and posterior spinal fusion
Anterior spinal fusion
In situ posterior fusion
Halo traction correction and posterior fusion
Continued soft cervical collar treatment

Correct Answer: Anterior and posterior spinal fusion

Explanation:

DISCUSSION: With a diagnosis of neurofibromatosis and severe kyphosis, anterior and posterior treatment is needed to achieve correction and fusion. In situ fusion has a high failure rate with the kyphotic deformity and even with traction, correction of the kyphosis is not expected. Anterior treatment alone may achieve correction, but in neurofibromatosis only circumferential treatment has been shown to provide long-term stability.
REFERENCES: Crawford AH, Schorry EK: Neurofibromatosis update. J Pediatr Orthop 2006;26:4I3- 423. MehJman CT, Al-Sayyad MJ, Crawford AH: Effectiveness of spinal release and halo-femoral traction in the management of severe spinal deformity. J Pediatr Orthop 2004;24:667-673.

Question 95:

Options:

a lace-up ankle splint and progressive activities.
anatomic repair of the anterior talofibular and calcaneofibular ligaments.
Kirschner wire and tension band fixation of the cortical avulsion fracture off the fibula.
local ligament transfer and reconstruction of the lateral ankle ligaments.
protected weight bearing and a short leg cast for 6 weeks.

Correct Answer: protected weight bearing and a short leg cast for 6 weeks.

Explanation:

Question 96:

Options:

fracture kyphosis.
reduction of retropulsed bone.
pain reduction.
incidence of complications.
return to work.

Correct Answer: incidence of complications.

Explanation:

Question 97:

Options:

Presence of a third-party abrasive particle
Disproportionate use of the limbs by the patient
Defective femoral head
Method of fixation of the femoral component
Method of sterilization and shelf life of the polyethylene

Correct Answer: Method of sterilization and shelf life of the polyethylene

Explanation:

DISCUSSION: Over the past three decades, gamma irradiation and air has been the most common method of sterilizing polyethylene used in total joint arthroplasty. This method of sterilization results in breakage of the chemical bonds within the polymer. While this promotes cross-linking, it also leaves the polyethylene vulnerable to oxidation, especially if packaged in an air environment. Oxidation has been shown to decrease polyethylene’s molecular weight, ultimate tensile strength, elongation, and toughness which results in a stiffer, more brittle material that is less resistant to wear. Severity of oxidation and a decrease in mechanical properties have been shown to be related to the length of time that the component is exposed to air (the shelf life). Currier and associates studied the clinical performance of gamma irradiated in air polyethylene components that had been shelf aged. They demonstrated that for the first
5 years of shelf life, polyethylene oxidized rather slowly. However, polyethylene components with a shelf life of more than 5 years would be expected to have minimal mechanical toughness and would likely fail rapidly if implanted. Bohl and associates evaluated 135 patients who had undergone total knee arthroplasty. Survivorship at 5 years was 100% for components with a shelf life of less than 4 years, 89% for components with a shelf life of 4 to 8 years, and 79% for components with a shelf life of more than 8 years. Sychterz and associates reported no correlation between shelf life and true wear rates for components with a shelf life of less
than 3 years. In summary, both in vivo and in vitro data suggest that shelf life in excess of
3 to 5 years has a direct effect on wear of polyethylene.
REFERENCES: Currier BH, Currier JH, Collier JP, et al: Shelf life and in vivo duration: Impacts on performance of tibial bearings. Clin Orthop 1997;342:111-122.
Bohl JR, Bohl WR, Postak PD, et al: The Coventry Award: The effects of shelf life on clinical outcome for gamma sterilized polyethylene tibial components. Clin Orthop 1999;367:28-38.
Sychterz CJ, Young AM, Orishimo K, et al: The relationship between shelf life and in vivo wear for polyethylene acetabular liners. J Arthroplasty 2005;20:168-173.

Question 98:

Options:

Inferior gluteal
Medial femoral circumflex
Lateral femoral circumflex
Femoral

Correct Answer: Lateral femoral circumflex

Explanation:

Question 99:

A 12-year-old boy falls from a bicycle. A radiograph of his injured shoulder is shown in Figure 41. What is the optimal method of treatment?

Options:

Suture of the coracoclavicular ligament
Temporary plate fixation across the acromioclavicular joint
Immobilization in a shoulder spica cast
Sling immobilization
Reduction and temporary intramedullary fixation across the acromioclavicular joint

Correct Answer: Sling immobilization

Explanation:

DISCUSSION: The radiograph reveals a distal clavicle fracture. In children, a periosteal sleeve will remain attached to the intact coracoclavicular ligament, and as such, remodeling can be expected. Therefore, nonsurgical management with a sling is preferred. Surgical treatment is not necessary, and a shoulder spica cast offers no advantage over a simple sling.
REFERENCES: Bishop JY, Flatow EL: Pediatric shoulder trauma. Clin Orthop Relat Res 2005;432:41-48.

Question 100:

Options:

an aggressive program of stretching exercises.
soft-tissue release and subscapularis lengthening.
exchange of the modular humeral head to a smaller size, with glenoid arthroplasty.
revision of the humeral component, re-cutting of the humeral neck, soft-tissue releases, and glenoid arthroplasty.
glenohumeral arthrodesis.

Correct Answer: revision of the humeral component, re-cutting of the humeral neck, soft-tissue releases, and glenoid arthroplasty.

Orthopedic Surgery Board Review MCQs: Arthroplasty, Trauma & Spine Part 255

Orthopedic Surgery Board Review MCQs: Spine, Arthroplasty & Trauma | Part 187

Key Takeaway

About This Board Review Set

How to Use the Interactive Quiz

Topics Covered in Part 187

Sample Questions from This Set

Why Active MCQ Practice Works

Chapter Index