OITE & AAOS Orthopedic Board Review MCQs: Part 215

About This Board Review Set

This is Part 215 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.

How to Use the Interactive Quiz

Two distinct learning modes are available:

Study Mode — After selecting an answer, you immediately see whether you are correct or incorrect, together with a full clinical explanation and literature references.
Exam Mode — All feedback is hidden until you click Submit & See Results. A live timer tracks elapsed time. A percentage score and detailed breakdown are displayed upon submission.

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 215

This module focuses heavily on: Foot, Fracture, Ligament, Nerve, Spine.

Sample Questions from This Set

Sample Question 1: Following a fall from a height of 5 feet, a patient reports pain along the lateral border of the foot. The CT scan shown in Figure 54 indicates what pathology?...

Sample Question 2: Limited weight bearing usually is recommended following open reduction and internal fixation of intra-articular lower extremity fractures. A bone graft, or bone graft substitute is often placed in the metaphyseal void beneath the reduced ar...

Sample Question 3: A 58-year-old African-American female who sustained an injury to her upper arm six months ago presents with persistent arm pain. She was initially treated with splinting, with conversion to fracture bracing. She is neurovascularly intact. A...

Sample Question 4: In a retroperitoneal approach to the lumbar spine, what nerve is commonly found on the psoas muscle?...

Sample Question 5: When making a comparison to autograft incorporation, the inflammatory process in allograft tissue anterior cruciate ligament (ACL) reconstruction...

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

00:00

Start Quiz

Question 1

Following a fall from a height of 5 feet, a patient reports pain along the lateral border of the foot. The CT scan shown in Figure 54 indicates what pathology?

Explanation

DISCUSSION: The CT scan reveals an avulsion of the dorsal beak of the anterior process of the calcaneus. This common fracture is an avulsion of the origin of the bifurcate ligament, which runs from the anterior calcaneal process to both the cuboid and the lateral aspect of the navicular. An inversion mechanism is common, and the fracture is often missed in evaluation for a suspected ankle sprain. MRI may be useful in the diagnosis of these occult injuries, and suspicion should be present when tenderness exists over the superior portion of the anterior process of the calcaneus.
REFERENCE: Robbins MI, Wilson MG, Sella EJ: MR imaging of anterosuperior calcaneal process fractures. Am J Roentgenol 1999;172:475-479.

Question 2

Limited weight bearing usually is recommended following open reduction and internal fixation of intra-articular lower extremity fractures. A bone graft, or bone graft substitute is often placed in the metaphyseal void beneath the reduced articular fragments. Which of the following bone grafts or bone graft substitutes will most likely permit earlier weight bearing without subsidence of the articular reduction?

Explanation

Most bone graft substitutes have a low compressive strength, similar to cancellous bone. Calcium phosphate cements, when hardened, have a much higher compressive strength compared to any of the other bone grafts or bone graft substitutes. In a study of 26 patients undergoing open reduction and internal fixation of displaced tibial plateau fractures, calcium phosphate was found to produce good outcomes. Because of the high mechanical strength of the cement, the authors allowed early weight bearing after a mean postoperative period of 4.5 weeks, with a range from 1 to 6 weeks. Despite early weight bearing, only two patients in this series had a partial loss of reduction. In biomechanical studies of displaced tibial plateau fractures, calcium phosphate compared favorably to cancellous bone graft. In one clinical series of patients undergoing open reduction and internal fixation for a calcaneus fracture, those patients whose reductions were supported with calcium phosphate were allowed to begin full weight bearing at 3 weeks and displayed no radiographic evidence of reduction loss. The effectiveness of calcium phosphate to resist deformation with cyclical loading in simulated calcaneal fractures has been confirmed in a biomechanical study.

Question 3

A 58-year-old African-American female who sustained an injury to her upper arm six months ago presents with persistent arm pain. She was initially treated with splinting, with conversion to fracture bracing. She is neurovascularly intact. An injury radiograph and a current radiograph are shown in Figures A and B respectively. What nutritional or metabolic disturbance is the most likely associated with this patient's diagnosis? Review Topic

Explanation

This patient has sustained a humeral diaphyseal fracture that has gone on to an atrophic nonunion. Vitamin D deficiency is the most likely associated metabolic disturbance.
The incidence of nonunion with non-operative management of humeral shaft injuries ranges from 2-10%. Risk factors include vitamin D deficiency (most common), open fractures, segmental injuries, smoking and obesity. The optimal treatment is compression plating with bone grafting, which has been shown to be superior to intramedullary nailing with bone grafting or compression plating alone.
Ring et al. reviewed factors that contributed to humeral diaphyseal nonunion after fracture bracing. Fractures in the proximal to middle one-third of the shaft or fractures with a spiral/oblique pattern were more likely to go on to nonunion.
Brinker et al. reviewed 37 low-energy fractures that went onto nonunion. These patients were evaluated by clinical endocrinologists for evaluation of metabolic abnormalities. Thirty-one of the 37 patients (84%) had a metabolic issue, with 68% (25 of 37 patients) having Vitamin D deficiency.
Figure A demonstrates a humeral shaft fracture. Figure B demonstrates an atrophic nonunion of the humeral shaft fracture.
Incorrect Answers:

Question 4

In a retroperitoneal approach to the lumbar spine, what nerve is commonly found on the psoas muscle?

Explanation

DISCUSSION: The genitofemoral nerve and the sympathetic plexus consistently lie on the ventral surface of the psoas muscle. The ilioinguinal and iliohypogastric nerves are the most superior branches of the lumbar plexus and emerge along the upper lateral border of the psoas muscle traveling toward the quadratus lumborum. Both the obturator and femoral nerves are deep and lateral to the psoas muscle.
REFERENCES: Watkins RG (ed): Surgical Approaches to the Spine, ed 1. New York, NY, Springer-Verlag, 1983, p 107.
Johnson R, Murphy M, Southwick W: Surgical approaches to the spine, in Herkowitz HH (ed): The Spine, ed 4. Philadelphia, PA, WB Saunders, 1992, p 1559.
Gray’s Anatomy. New York, NY, Bounty Books, 1977, pp 1226-1227.

Question 5

When making a comparison to autograft incorporation, the inflammatory process in allograft tissue anterior cruciate ligament (ACL) reconstruction

Explanation

Compared to similar autograft, allograft tissue demonstrates a prolonged inflammatory response, slower rate of biological incorporation and remodeling, and a higher proportion of large-diameter collagen fibrils. Native ACL inserts into bone through a transition of 4 distinct zones: tendon, unmineralized fibrocartilage, mineralized fibrocartilage, and bone. This transition is not reproduced with tendon grafts, which instead heal with interposed fibrovascular scar at the graft-tunnel interface. The scar rapidly remodels to form perpendicular fibers resembling Sharpey fibers and, eventually, mature bone growth into the outer portion of the graft. The intra-articular portion of allograft undergoes an initial phase of necrosis followed by repopulation by host synovial cells into the acellular collagen scaffold. Revascularization and maturation complete the ligamentization of graft tissue.

Question 6

Figure 3a is the initial radiograph of a 19-year-old man who sustained a closed clavicle fracture. Figures 3b and 3c show postoperative radiographs. If the patient had been treated nonsurgically, which of the following would most likely occur?

Explanation

Recent studies comparing surgical treatment with nonsurgical management in displaced clavicle fractures have revealed a decreased rate of malunion and nonunion with surgery. In addition, significant malunions can lead to functional deficits at the shoulder. Thus, with open reduction and internal fixation and anatomic or near-anatomic reduction, there should be a higher likelihood of normal shoulder strength and function. Infection and local sensory deficits would not be expected with nonsurgical management, whereas surgical treatment has a small risk of infection and a high likelihood of sensory deficits from iatrogenic damage to the supraclavicular nerves.

Question 7

Radiographs shown in Figures 1 through 3 show two different prosthetic design variations of the same knee implant. When compared with the design of right knee prosthesis, the left can be expected to have a

Explanation

A 76-year-old woman has had three hip revisions for instability. She presents to the emergency department with another dislocation that occurred while getting up from a low chair. Current radiographs are shown in Figures 1 and 2. Her prior AP pelvis radiograph is shown in Figure 3. ESR and CRP are normal. What is the best plan for definitive treatment?

Question 8

An 18-year-old football halfback reports that he had immediate right knee pain after being tackled 1 week ago. Examination now reveals moderate tenderness over the proximal medial tibia and lateral joint and normal cruciate stability. In evaluating the integrity of the posterolateral knee structures, what is the most reliable examination finding?

Explanation

DISCUSSION: The most reliable test for a relatively isolated posterolateral complex (PLC) injury is the asymmetric tibial external rotation or “dial test.” It can be performed with the patient prone or supine. When greater than 10 degrees of external rotation at 30 degrees of flexion is present when compared with the opposite knee, it indicates significant damage to the posterolateral structures. Asymmetric external rotation, which is also present at 90 degrees of flexion, indicates injury to the posterior cruciate ligament (PCL) as well. Varus laxity may indicate significant damage to both the PLC and PCL. Approximately 35% of the normal population may have a reverse pivot shift when examined under anesthesia; therefore, it is considered a less specific test. The external rotation/recurvatum and posterolateral drawer tests are adjunctive in assessing isolated posterolateral laxity but are not thought to be as reliable.
REFERENCES: Veltri DM, Warren RF: Isolated and combined posterior cruciate injuries. J Am Acad Orthop Surg 1993;1:67-75.
Koval KJ (ed): Orthopaedic Knowledge Update 7. Rosemont IL, American Academy of Orthopaedic Surgeons, 2002, pp 489-511.

Question 9

A previously healthy 14-year-old boy now reports fatigue, and has a bilateral Trendelenburg gait, right hip pain, and bilateral knee and foot pain. Biopsy of a right sacral mass reveals intermediate grade osteosarcoma. There are no metastases. Laboratory studies reveal a serum calcium level of 7.7 mg/dL (normal 8.5 to 10.5), a phosphate level of 2.0 mg/dL (normal 2.7 to 4.5), a 1,25-dihydroxyvitamin D level of less than 10 pg/mL (normal 18 to 62), a parathyroid hormone level of 19 pg/mL (normal 10 to 60), and an alkaline phosphatase level of 428 U/L (normal 15 to 351). What is the most likely cause of the patient’s symptoms?

Explanation

DISCUSSION: The laboratory findings are typical for rickets. Oncogenic rickets is a paraneoplastic syndrome that results from a substance secreted by the tumor that interferes with renal tubule reabsorption of phosphate. This substance previously had been called phosphatonin but recently has been identified as fibroblast growth factor 23. Nutritional rickets is rare in developed countries. Delayed onset familial hypophosphatemic rickets is possible, but the likelihood of having two rare diseases is unlikely. Osteosarcoma does not sequester calcium. Alkaline phosphatase levels can be elevated in osteosarcoma but does not cause muscle weakness. Tumor cachexia would occur only with advanced metastatic disease. A unilateral sacral mass would not cause a bilateral L5 neuropathy or the abnormal laboratory findings.
REFERENCES: Case records of the Massachusetts General Hospital. Weekly clinicopathological exercises. Case 29-2001. A 14-year-old with abnormal bones and a sacral mass. N Engl J Med 2001;345:903-908.
Jonsson KB, Zahradnik R, Larsson T, White KE, Sugimoto T, Imanishi Y, et al: Fibroblast growth factor 23 in oncogenic osteomalacia and X-linked hypophosphatemia. N Engl J Med 2003;348:1656-1663.

Question 10

Figures 51a and 51b show the AP and lateral radiographs of the elbow of a 26-year-old man who fell. Closed reduction was performed in the emergency department, and management consisted of immobilization for 3 weeks prior to the initiation of motion. At 12 weeks after injury, he reports continued feelings of instability and catching in his elbow when using his arms to rise from a chair. Which of the following procedures needs to be performed, at a minimum, to reestablish stability of the elbow? Review Topic

Explanation

The patient has chronic posterolateral instability of the elbow following dislocation. The lateral collateral ligament complex is responsible for maintaining stability of the elbow. Because of the chronicity of the injury, the ligamentous tissues are frequently attenuated and not amenable to simple repair; while the native ligament can be imbricated, reconstruction with allograft or autograft is recommended. Medial collateral ligament reconstruction or hinged external fixation is needed only if restoration of the lateral ligamentous complex does not restore elbow stability; however, these procedures are rarely required. Lateral elbow pain when rising from a chair is equivalent to a positive pivot shift test.

Question 11

Varus malalignment after a talar neck fracture with medial comminution causes a decrease in what motion?

Explanation

DISCUSSION: Varus alignment at the talar neck results in a decrease in subtalar eversion before impingement occurs. Varus talar neck alignment can cause a fixed internal rotation position of the midfoot as the navicular follows the talar head. This can lead to a more rigid hindfoot which is specifically manifested as a decreased eversion range of motion.
Herscovici et al review the appropriate management of complex ankle and hindfoot injuries in this instructional course lecture.
Daniels et al performed a cadaveric study where they osteotomized the talar neck and then studied ankle motion with and without removal of a medially based wedge of bone. They found that subtalar eversion was specifically decreased.
Sanders et al found that secondary reconstructive procedures following talar neck fractures were most commonly performed to treat subtalar arthritis or misalignment.

Question 12

Scapular notching following reverse shoulder arthroplasty may be minimized by what technical modification? Review Topic

Explanation

Biomechanical studies have shown that a 10-degree inferior inclination may decrease scapular notching; whereas superior inclination may worsen notching. Scapular notching has been recognized as a complication following reverse shoulder arthroplasty. Mechanical abutment of the humeral component possibly leads to erosion of the anteroinferior scapular neck, with progressive vulnerability of the inferior baseplate screws. A horizontal humeral cut does not affect notching because the humeral component causes the notching, not the bone on the humerus. Glenosphere size has not been shown to correlate with scapular notching.

Question 13

A 71-year-old woman has a failed revision hip arthroplasty and is undergoing a re-revision hip arthroplasty. Her last hip surgery was 4 years ago with revision of the acetabular component. Radiographs show a well-fixed extensively porous-coated femoral component and a failed acetabular component with proximal and medial migration through the floor of the acetabulum. Preoperative laboratory studies reveal an erythrocyte sedimentation rate (ESR) of 70 mm/h (normal 0-29 mm/h), a C-reactive protein (CRP) of 23.3 (normal 0.2-8.0), and a negative hip aspiration. At the time of surgery, tissues look inflamed and a frozen section shows 20 WBC per high power field; however, a Gram stain is negative. What is the most appropriate action at this point?

Explanation

DISCUSSION: Despite the negative aspiration preoperatively, intraoperative findings are suspicious for infection. Additionally, the preoperative blood work is also concerning for infection with an elevated CRP and ESR. The frozen section is also positive. Most important is the unreliability of the Gram stain. Numerous investigators have show high false negative rates for Gram stain in chronic periprosthetic infection. The Gram stain should not be relied on for decision-making in revision surgery, particularly when other investigations point to infection. With the information available, the diagnosis is deep infection. The best course of action is to obtain cultures, remove the implants, and insert an antibiotic spacer. Only obtaining cultures and closing would require a second operation to remove the implants if the cultures are positive.
REFERENCES: Sanzen L, Sundberg M: Periprosthetic low-grade hip infections: Erythrocyte sedimentation rate and C-reactive protein in 23 cases. Acta Orthop Scand 1997;68:461-465.
Spangehl MJ, Hanssen AD, Osman DR: Diagnosis and treatment of the infected hip arthroplasty, in Morrey BF(edA)L:-MJoaidnetnaRCeopplyacement Arthroplasty, ed 3. Philadelphia, PA, Churchill Livingstone, 2003, pp 856-874. Question 71
A 79-year-old patient has a history of peripheral vascular disease and reports chronic knee pain. She has had coronary artery disease treated with angiography and stents on two occasions. Peripheral pulses are absent in both lower extremities, but the patient is disabled by advanced chronic degenerative arthritis in her right knee and would like to proceed with a total knee arthroplasty. The next most appropriate evaluation should include which of the following?
Ankle-brachial index of the affected lower extremity
Femoral popliteal angiography
Venous Dopplers of both lower extremities
MRI of the popliteal fossa
Radiographs to identify calcified plaques in the femoral artery
DISCUSSION: This question is designed to draw attention to the fact that peripheral vascular disease carries an increased risk of complications for the patient and should be carefully evaluated. The vascular surgeon will make the choice of revascularization or surgical clearance for knee reconstruction based on the initial results of the ankle-brachial index.

REFERENCE: Smith DE, McGraw RW, Taylor DC, et al: Arterial complications and total knee arthroplasty. J Am Acad Orthop Surg 2001 ;9:253-257.

Question 14

An otherwise healthy 78-year-old woman has low back and buttock pain. Rectal examination reveals a large sacral mass. Figures 7a and 7b show a CT scan and a sagittal MRI scan of the lumbosacral spine. A biopsy specimen is shown in Figure 7c. What is the most likely diagnosis?

Explanation

DISCUSSION: A chordoma is a malignant neoplasm originating from remnants of the notochord. It is usually localized to the midline with 50% at the sacrococcygeal area, 35% at the skull base, and 15% at the mobile portion of the spine. Large vacuolated cells (physaliferous cells) are a characteristic of the tumor.
REFERENCES: Mindell ER: Chordoma. J Bone Joint Surg Am 1981;63:501-505.
Samson IR, Springfield DS, Suit HD, Mankin HJ: Operative treatment of sacrococcygeal chordoma: A review of twenty-one cases. J Bone Joint Surg Am 1993;75:1476-1484.

Question 15

A 45-year-old right-hand dominant woman falls onto an outstretched left hand. Imaging shows a complex elbow dislocation. The postreduction CT scan demonstrates a reduced joint, comminuted radial head fracture, and type I coronoid fracture. Surgical intervention is recommended to address the involved structures. Which component of the intervention adds the most rotational stability?

Explanation

A 68-year-old right-hand dominant woman has experienced progressive right elbow pain and loss of motion for several years. She has failed nonsurgical treatment and elects to undergo a total elbow arthroplasty (TEA). In comparison to a linked prosthesis, an unlinked prosthesis has which reported distinction with extended follow-up?
A. Improved longevity in comparison to the linked prosthesis
B. A significantly larger flexion-extension arc
C. A higher incidence of postsurgical instability
D. Lower frequency of ulnar nerve dysfunction
TEA is a popular option for treatment of end-stage elbow arthritis for elderly, lower-demand patients with rheumatoid arthritis. Good success rates have been published by several authors. The clear benefit of the current nonconstrained prosthesis has yet to be proven. Plaschke and associates investigated the Danish National Patient Registry to compare the longevity of the 2 types of implants. These authors found similar survival rates associated with both linked and unlinked implants at 10 years (88% and 77%, respectively). However, studies have documented an approximate 20% incidence of postsurgical instability with nonconstrained implants.

Question 16

What normal tissue has a low signal intensity (appears black) on both T1- and T2-weighted images?

Explanation

DISCUSSION: Tendons, cortical bone, ligaments, menisci, and fibrous tissue will show low signal intensity (SI) on both T1- and T2-weighted images. Fat-containing tissues, such as subcutaneous fat and bone marrow, will show high SI on T1-weighted images and low SI on T2-weighted images. Tissues with high water content, such as joint fluid, intervertebral disk, and edema, will show low SI on T1-weighted images and high SI on T2-weighted images.
REFERENCES: Kasser JR (ed): Orthopaedic Knowledge Update 5. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1996, pp 65-70.
Slucky AV, Potter HG: Use of magnetic resonance imaging in spinal trauma: Indications, techniques, and utility. J Am Acad Orthop Surg 1998;6:134-145.

Question 17

A 24-year-old man sustained a bilateral C5-6 facet dislocation in a car accident and was intubated at the scene. He remains sedated in the intensive care unit

Explanation

The MRI finding that most consistently corresponds with a complete spinal injury is a hematoma within the cord. Cord edema can predict a poor prognosis if it is more extensive but is not considered as consistent a finding. Ligamentous injury about the neck can indicate musculoskeletal instability but it does not in and of itself indicate the presence or predict the severity of spinal cord injury. Likewise, soft-tissue edema anterior to the spine may indicate musculoskeletal injury but does not offer specific information regarding the presence or absence of cord injury.

Question 18

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 19

According to Musculoskeletal Infection Society (MSIS) guidelines, which set of patient laboratory study results fits the definition of chronic prosthetic joint infection?

Explanation

DISCUSSION:
The MSIS definition of periprosthetic joint infection was updated in 2014 with two major and six minor criteria. The presence of one major criterion or three minor criteria is diagnostic for infection. The major criteria are two positive cultures with the same organism or a draining sinus tract. The current MSIS minor criteria are 1) an elevated ESR (more than 30 mm/hr) and CRP level (more than 10 mg/L), 2) an elevated synovial WBC count (more than 3,000 cells per/microliter), 3) an elevated synovial fluid polymorphonuclear count (more than 80%), 4) a positive histological analysis of periprosthetic tissue, and 5) a single positive culture.

Question 20

An 80-year-old woman notes a painless mass posterior to her left knee. MRI scans are shown in Figures 31a and 31b. What is the best course of action?

Explanation

DISCUSSION: The MRI scans show a popliteal cyst (Baker’s cyst) in its most common location. The cyst emerges from the knee joint between the medial head of the gastrocnemius muscle and the tendon of the semimembranosus muscle. These images are diagnostic; therefore, no further work-up is indicated. Since the patient is asymptomatic, no treatment is necessary.
REFERENCES: Dlabach JA: Nontraumatic soft tissue disorders, in Canale ST (ed): Campbell’s Operative Orthopaedics, ed 10. Philidelphia, PA, Mosby, 2003, vol 1, pp 885-969.
Fritschy D, Fasel J, Imbert JC, et al: The popliteal cyst. Knee Surg Sports Traumatol Arthrosc 2006;14:623-628.

Question 21

Which of the following pieces of equipment currently offers the greatest opportunity for lowering the number of equestrian injuries?

Explanation

DISCUSSION: Ball and associates reported that “horseback riding was more dangerous than motorcycle riding.” In a 10-year study of major traumatic injuries, they reported that 151 (2%) of 7,941 trauma patients had major equestrian injuries (injury severity score > or = 12). Injuries included the chest (54%), head (48%), abdomen (22%), and extremities (17%). Only 9% of riders wore helmets, and 64% believed the accident was preventable. The authors noted that “helmet and vest use will be targeted in future injury prevention strategies.” In another study, Frankel and associates noted that helmet use was only documented in 34% of riders. Although orthopaedic injuries are common, knee pads, wrist guards, boots, and quick release stirrups would most likely have less impact on injury prevention.
REFERENCES: Ball CG, Ball JE, Kirkpatrick AW, et al: Equestrian injuries: Incidence, injury patterns, and risks factors for 10 years of major traumatic injuries. Am J Surg 2007;193:636-640.
Frankel HL, Haskell R, Digiacomo JC, et al: Recidivism in equestrian trauma. Am Surg 1998;64:151-154.
A 38-year-old man is three quarters of the way through the Hawaiian Ironman events run in a temperature of 60°F. He is sweating profusely and suddenly collapses. Prior to this he had been drinking large amounts of bottled water at every water stop. What is the most likely diagnosis?
Hypernatremia
Hypothermia
Hyponatremia
Subendocardial myocardial infarction
Ruptured berry aneurysm
DISCUSSION: Hyponatremia is often seen in endurance athletes such as triathloners, ultramarathoners, and marathoners after prolonged exertion. It is commonly attributed to excess free water intake that fails to replete massive sodium losses that result from sweating as reported by O’Connor. Exercise-induced hyponatremia is generally asymptomatic, particularly in patients in whom the sodium is only mildy reduced. Up to 10% of ultradistance athletes have a sodium level of 135 mEq/L or less, but those who are symptomatic usually have a sodium level of 125 mEq/L as reported by Noakes and O’Connor. The best way to prevent hyponatremia is to maintain the proper volume and types of fluid intake to ensure fluid balance during exercise. Beverages containing carbohydrates in concentrations of 4% to 8% (ie, “sports drinks”) are recommended for athletes participating in exercise lasting more than an hour (eg, marathon runners, etc.) To avert brainstem herniation and death, severe, acute hyponatremia requires rapid correction. Oral rehydration with salty solutions is safe and effective in patients with mild symptoms.
Too rapid correction has been reported to cause central pontine myelinolysis; therefore, correction ought to be performed slowly. Hypernatremia, hypothermia, subendocardial myocardial infarction, or ruptured berry aneurysm are unlikely in this scenario.
REFERENCES: O’Connor RE: Exercise-induced hyponatremia: Causes, risks, prevention, and management. Cleve Clin J Med 2006;73:S13-S18.
Noakes T: Hyponatremia in distance runners: Fluid and sodium balance during exercise. Curr Sports Med Rep
2002;1:197-207.
Laureno R, Karp BI: Myelinolysis after correction of hyponatremia. Ann Int Med 1997;126:57-62. Question 50
A 20-year-old male tennis player reports the acute onset of ulnar-sided wrist pain after hitting a forehand shot. Examination reveals dorsoulnar tenderness and minimal swelling. The pain is recreated with supination, wrist flexion, and ulnar deviation. Radiographs are normal. What structure is most likely involved?
Ulnar styloid
Flexor carpi radialis tendon
Extensor carpi ulnaris tendon
Scapholunate ligament
Transverse carpal ligament PREFERRED RESPONSE: 3
DISCUSSION: Extensor carpi ulnaris (ECU) lesions produce pain at the dorsoulnar aspect of the wrist, particularly during wrist supination, wrist flexion, and ulnar deviation. It has been frequently described in tennis players. Most ECU tenosynovitis can be successfully treated nonsurgically with immobilization techniques. Surgical treatment is generally indicated for ECU tenosynovitis or tendinopathy that does not respond to rest. Anatomically, the ECU retinaculum can rupture and the tendon can leave its sheath. With supination, the tendon can leave the sheath and then return to its position during pronation.
REFERENCES: Montalvan B, Parier J, Brasseur JL, et al: Extensor carpi ulnaris injuries in tennis players: A study of 28 cases. Br J Sports Med 2006;40:424-429.
Allende C, Le Viet D: Extensor carpi ulnaris problems at the wrist: Classification, surgical treatment and results. J Hand Surg Br 2005;30:265-272.

Question 22

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 23

A 17-year-old male soccer player sustains repeated lateral patellar dislocations refractory to physical therapy, bracing, and taping. After a workup including radiographs and MRI, the orthopaedic surgeon considers an isolated tibial tubercle osteotomy (TTO). He plans a 60-degree anteromedialization to address instability and to unload the patellofemoral joint. What is a relative contraindication to this procedure?

Explanation

CLINICAL SITUATION FOR QUESTIONS 37 THROUGH 41
A healthy, active 18-year-old man has acute-onset right knee pain and an inability to fully extend his knee following an attempt to stand from a seated position yesterday. He sustained a noncontact injury to his right knee while playing basketball 2 years ago and underwent primary anterior cruciate ligament (ACL) reconstruction with bone-patella-tendon-bone autograft and medial meniscus repair. He sustained another noncontact injury to the same knee 8 months later and underwent a revision ACL reconstruction using soft-tissue allograft and revision medial meniscus repair. He reports multiple episodes of “giving way” of his knee, but no pain prior to yesterday’s acute injury.

Question 24

A 35-year-old man who is involved in an improvised explosive device attack is hit by a piece 57 of shrapnel. He has a solitary penetrating wound in his left tibia. Radiographs show no fracture. He has significant pain and his calf is grossly swollen. He has good sensation and palpable dorsalis pedis and tibialis posterior pulses. He has elevated pressure in all 4 compartments. When performing a 4-compartment fasciotomy using the 2-incision technique, which structure is at risk when opening the deep posterior compartment?

Explanation

DISCUSSION
Compartment syndrome is commonly seen in lower-extremity trauma, especially in blast injuries or high-energy trauma to the lower extremity. It is important to recall the neurovascular structures present in each of the 4 compartments. The posterior tibial artery is in the deep posterior compartment along with the tibial nerve, the peroneal artery and vein, and the posterior tibial vein. The lateral compartment contains the superficial peroneal nerve.
The anterior compartment contains the deep peroneal nerve and the anterior tibial artery and vein. The superficial posterior compartment does not have any neurovascular structures. The saphenous nerve is superficial.
RECOMMENDED READINGS
Thompson JC, ed. Netter’s Concise Atlas of Orthopaedic Anatomy. Teterboro: NJ: Icon Learning Systems; 2002.
Mubarak SJ, Owen CA. Double-incision fasciotomy of the leg for decompression in compartment syndromes. J Bone Joint Surg Am. 1977 Mar;59(2):184-7. PubMed PMID: 15455478.View Abstract at PubMed

Question 25

Figures 8a and 8b show the clinical photograph and radiograph of a 4-month-old infant who has a left foot deformity. Examination reveals that the foot deformity is an isolated entity, and the infant has no known neuromuscular conditions or genetic syndromes. Which of the following studies will best confirm the diagnosis?

Explanation

DISCUSSION: The clinical photograph shows a rocker-bottom deformity, and the lateral radiograph suggests a congenital vertical talus deformity. A lateral radiograph of the foot in maximum plantar flexion is needed to demonstrate the fixed position of the deformity with malalignment of the talar-metatarsal axis. A fixed dislocation of the navicular on the talus differentiates a congenital vertical talus from the oblique talus with talonavicular subluxation.
REFERENCES: Kumar SJ, Cowell HR, Ramsey PL: Vertical and oblique talus. Instr Course Lect 1982;31:235-251.
Kodros SA, Dias LS: Single-stage correction of congenital vertical talus. J Pediatr Orthop 1999;19:42-48.
Herring JA: Disorders of the foot, vertical talus, in Herring JA (ed): Tachdjian’s Pediatric Orthopaedics, from the Texas Scottish Rite Hospital for Children, ed 3. Philadelphia, PA,

WB Saunders, 2002, pp 959-967.

Question 26

Which radiographic abnormality most accurately serves as a predictor of ankle syndesmosis disruption?

Explanation

DISCUSSION
Normal syndesmotic relationships include a tibiofibular clear space smaller than 6 mm on both AP and mortise views. In a 1989 cadaveric study by Harper and Keller, a tibiofibular clear space exceeding 6 mm on both the AP and mortise views was the most reliable predictor of early syndesmotic widening. Tibiofibular overlap is measured 1 cm proximal to the plafond. Normal values exceed 6 mm or 42% of the width of the fibula on the AP view, or 1 mm on the mortise view. Proximal fibula fracture can occur in isolation without syndesmotic injury, frequently after direct trauma. The medial clear space is the distance between the lateral border of the medial malleolus and the medial border of the talus and is measured at the level of the talar dome. In the mortise view with the ankle in neutral dorsiflexion, the medial clear space should be equal to or smaller than the superior clear space between the talar dome and the tibial plafond. ?A normal medial clear space may be present with syndesmotic injury and consequently lacks sensitivity and specificity.
RECOMMENDED READINGS
Zalavras C, Thordarson D. Ankle syndesmotic injury. J Am Acad Orthop Surg. 2007 Jun;15(6):330-9. Review. PubMed PMID: 17548882. View Abstract at PubMed
Wuest TK. Injuries to the Distal Lower Extremity Syndesmosis. J Am Acad Orthop Surg. 1997 May;5(3):172-181. PubMed PMID: 10797219. View Abstract at PubMed
Harper MC, Keller TS. A radiographic evaluation of the tibiofibular syndesmosis. Foot Ankle. 1989 Dec;10(3):156-60. PubMed PMID: 2613128. View Abstract at PubMed
CLINICAL SITUATION FOR QUESTIONS 37 THROUGH 40
A 41-year-old man sustained a twisting injury while running up stairs 4 weeks ago. He was treated in an ankle brace and has been bearing weight since the injury occurred. He has no history of ankle problems, but he now has ankle pain, swelling, and instability. The pain is aggravated by stairs, and the instability is worse on unlevel ground. Radiographs do not show a fracture.

Question 27

A 56-year-old man sustained a nondisplaced extra-articular fracture of the proximal aspect of the third metatarsal after dropping a heavy object on his left foot. Management should consist of

Explanation

DISCUSSION: This injury pattern is one of a direct trauma to the mid aspect of the foot. Without additional forces involved, capsular ligamentous injury is not anticipated; therefore, the injury should be a stable pattern. Treatment should consist of protected weight bearing as tolerated in a walking boot or walking cast. Surgical intervention with open reduction and internal fixation, percutaneous pinning, or open reduction and internal fixation with primary tarsometatarsal joint fusion is not indicated with this pattern of injury. The use of external bone stimulation in this acute fracture setting is not indicated. With injuries to the midfoot area where the exact mechanism of injury is uncertain, there should be a high index of suspicion for an associated injury to the tarsometatarsal joint, and standing radiographs or stress radiographs should be obtained.
REFERENCES: Myerson MS: Foot and Ankle Disorders. Philadelphia, PA, WB Saunders, 2000, pp 1265-1296.
Early JS: Fractures and dislocations of the midfoot and forefoot, in Rockwood and Green’s Fractures in Adults, ed 5. Philadelphia, PA, Lippincott Williams and Wilkins, 2001,

pp 2181-2245.

Question 28

The presence of S100B tumor marker typically corresponds with which of the following as being the most likely source of the metastasis?

Explanation

DISCUSSION: Advances in development of new tumor markers and techniques of antigen retrieval have enhanced the sensitivity and reliability of identifying the primary source of metastasis. New markers such as CK7, CK20, CA125, and thyroid transcription factor-1

(TTF-1) can help to determine the origin of an adenocarcinoma or aid in the recognition of other tumors. In patients who do not have an obvious primary site of disease or screening radiographs, these new markers can help focus the search for and guide the treatment of the underlying lesion. CA125 is positive in patients with ovarian cancer, CK7 is positive in patients with breast and lung carcinoma, and CK20 is indicative of colon carcinoma if the CK7 marker is negative. Gastrointestinal stromal tumor (GIST) is positive for CD117 (c-kit) and CD34, whereas 75% of bronchogenic carcinomas are positive for TTF-1. Histochemical staining of the S100 protein family has been used for many years in the diagnosis of malignant melanoma. Recent markers HMB-45, MART-1, and Melan-A have proved to be useful in diagnosis of melanoma. S100B protein has been implicated in downregulation of p53 (oncosuppressor gene).
REFERENCES: Harpio R, Einarsson R: S100 proteins as cancer biomarkers with focus on S100B in malignant melanoma. Clin Biochem 2004;37:512-518.
Roodman GD: Mechanisms of bone metastasis. N Engl J Med 2004;350:1655-1664.

Question 29

On physical examination, he has no open wounds and is neurologically intact in both lower extremities. Imaging of the right femur (Figures A and B) and the left femur (Figures C and D) is shown. What is the next best step in treatment?

Explanation

may be performed.
OrthoCash 2020

Question 30

Figure 43 shows the lateral radiograph of a 12-year-old boy with mild osteogenesis imperfecta who injured his left elbow after pushing his brother. Treatment should consist of

Explanation

DISCUSSION: The patient has a displaced fracture of the apophysis of the olecranon for which most authorities recommend surgical treatment. In older children, stability of the reduction may be achieved by the use of two parallel medullary Kirschner wires and a figure-of-8 tension band loop of either stainless steel wire or absorbable suture. The use of an absorbable suture does not require removal of the implant. Absorbable suture alone is best used in very young patients who have this type of injury. An intramedullary screw would pose an unnecessary risk of future growth disturbance.
A displaced, isolated fracture of the apophysis of the olecranon is an unusual injury in a child. It has been suggested by several authors that children who have osteogenesis imperfecta may be especially prone to this injury. One study reported seven of these fractures occurring in five children who had the mild form of osteogenesis imperfecta (Sillence type IA). The authors of this study suggest that the diagnosis of osteogenesis imperfecta be considered in any child who has a displaced fracture of the apophysis of the olecranon, especially when the injury is associated with relatively minor trauma.
REFERENCES: Stott NS, Zionts LE: Displaced fractures of the apophysis of the olecranon in children who have osteogenesis imperfecta. J Bone Joint Surg Am 1993;75:1026-1033.
Gaddy BC, Strecker WB, Schoenecker PL: Surgical treatment of displaced olecranon fractures in children. J Pediatr Orthop 1997;17:321-324.
Dormans JP, Rang M: Fractures of the olecranon and radial neck in children. Orthop Clin North Am 1990;21:257-268.

Question 31

What type of physical therapy is most effective for chronic noninsertional Achilles tendinopathy?

Explanation

DISCUSSION: Eccentric gastrocsoleus strengthening (especially with heavy loads) consistently has been shown to be superior in the management of Achilles tendinopathy. Decreases in pain and increases in strength have been demonstrated despite the frequently refractory nature of this condition.
REFERENCES: Richardson EG (ed): Orthopaedic Knowledge Update: Foot and Ankle 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2003, pp 91-102.
Vora AM, Myerson MS, Oliva F, et al: Tendinopathy of the main body of the Achilles tendon.

Foot Ankle Clin 2005;10:293-308.

Question 32

A 34-year-old female is involved in a high-speed motor vehicle collision and sustains a traumatic proximal forearm amputation. She successfully undergoes debridement and closure, and six weeks later, is fitted with her temporary prosthesis. In order to optimize her outcomes upon returning to work as a secretary, which of the following is recommended?

Explanation

Upper extremity trauma has serious, acute psychological effects that can linger long after the physical injury. These effects may negatively affect patient-reported outcomes, and may also be associated with worsening pain complaints. Coping and stress management techniques can be reviewed with formal psychological counseling, and should be offered to all patients who have underwent an amputation.
Richards et al surveyed 34 patients who had emergency upper extremity surgery and found high levels of psychological distress in patients, including 29% with high levels of both depression and post-traumatic stress disorder (PTSD). They also found that disability was strongly related to pain, depression, and PTSD symptoms.
Mallette et al assessed the attitudes of hand surgery patients and hand surgeons regarding psychologic influences on illness and compared their attitudes with those of the general population. They found that surgeons underestimated the openness of patients to discuss psychological issues and that patients believed in the strong effect of psychologic factors on healing and pain.
Illustration A shows a myoelectric prosthesis in a military veteran. Incorrect Answers:

Question 33

A healthy 16-year-old boy has had increasing pain in the right knee for the past 3 months. Examination reveals warmth and swelling around the distal femur. Radiographs and an MRI scan are shown in Figures 51a through 51c, and a biopsy specimen is shown in Figure 51d. What is the most likely diagnosis?

Explanation

DISCUSSION: The radiographs show a bone-producing lesion in the distal femoral metaphysis in this case of classic osteosarcoma presenting in the most common location, the distal femur. The coronal MRI scan reveals a marrow-occupying lesion with extension into the soft tissues. The histology shows osteoid production by pleomorphic cells consistent with an osteosarcoma. Ewing’s sarcoma is a bone tumor characterized by uniform small blue cells on histology. Rhabdomyosarcoma is the most common childhood soft-tissue sarcoma. Osteomyelitis has an inflammatory appearance on histology. Malignant fibrous histiocytoma of bone has a lytic radiographic appearance and a pleomorphic storiform pattern without osteoid on histology.
REFERENCES: Wold LE, Adler CP, Sim FH, et al: Atlas of Orthopedic Pathology, ed 2. Philadelphia, PA, WB Saunders, 2003, p 179.
McCarthy EF, Frassica FJ: Pathology of Bone and Joint Disorders with Clinical and Radiographic Correlation. Philadelphia, PA, WB Saunders, 1998, p 205.

Question 34

A 10-year-old boy reports heel pain with sporting activities. An examination demonstrates gastrocnemius contracture and tenderness at the calcaneal apophysis. Radiographs are unremarkable. What is the best next step?

Explanation

DISCUSSION
Sever disease, or calcaneal apophysitis, is best treated with activity modification that includes rest, restriction from sports and running, and Achilles tendon stretching exercises. The diagnosis is clinical (rendering MRI study unnecessary) and the course is usually self-limited, obviating the need for surgery. Occasionally, children with severe symptoms may benefit from a short period of cast or fracture brace immobilization.
RECOMMENDED READINGS
Sullivan RJ. Adolescent foot and ankle conditions. In: Pinzur MD, ED. Orthopaedic Knowledge Update: Foot and Ankle 4. Rosemont, IL: American Academy of Orthopaedic Surgeons; 2008:47-55.
Feldman DS. Osteochondrosis. In: Spivak JM, Di Cesare PE, Feldman Ds, et al, eds. Orthopaedic: A Study Guide. New York, NY: McGraw-Hill; 1999:765-766.

Question 35

Figures 1 and 2 are the radiographs of a 36-year-old man who has had left wrist pain for the past 6 months following a fall onto his outstretched arm. Examination reveals a positive ballottement test, dorsal and ulnar carpal tenderness, and a painful snap with ulnar deviation, pronation, and axial compression. Injury to what ligament is the cause of this patient's pain?

Explanation

EXPLANATION:
The radiographs reveal a volarly tilted lunate on the lateral view (Figure 1) and an incongruous lunotriquetral articulation on the AP gripped view (Figure 2). The patient has what appears to be radiographic findings of volar intercalated segmental instability (VISI), a type of carpal instability, dissociative. An injury to the volar lunotriquetral ligament is the most important contributor to this type of instability. An injury to the dorsal scapholunate ligament typically leads to a dorsal intercalated segmental instability. Isolated injuries to the dorsal radiocarpal ligament and the radioscaphocapitate
ligament do not lead to VISI, although combined injuries may lead to instability between the radius and the proximal row.

Question 36

Figures 41a and 41b show the radiographs of a 22-year-old woman who has a bunion on her left foot. She denies pain in the foot, but she reports increasing difficulty with shoe wear. Management should consist of

Explanation

DISCUSSION: Surgery is not indicated in a patient who has a mild deformity and no pain. Shoe wear modifications should be recommended.
REFERENCE: Mann RA, Coughlin MJ: Surgery of the Foot and Ankle, ed 7. St Louis, MO, Mosby, 1999, p 174.

Question 37

After full healing from this injury, which option most likely will help to optimize this patient's activities?

Explanation

DISCUSSION
Midfoot fracture dislocations typically occur after a fall from a height or a motor vehicle collision involving severe dorsiflexion loading of the foot from a brake pedal or the floorboards. The deformity that results may be subtle because the subluxation may be a valgus or varus rotation around the midfoot rather than pure dorsiflexion. Early recognition and reduction is indicated to minimize secondary complications such as nerve injury or vascular compromise. Closed reduction usually necessitates formal anesthesia in an operating room to permit adequate relaxation and reduction. In many cases, satisfactory reduction can be accomplished closed, but the surgeon must be prepared to perform an open reduction if needed. The most common reason for failed closed reduction is that the talar head is caught by the tibialis posterior tendon (under which the talar head has protruded). This acts as a Chinese finger trap, preventing relocation by the usual distraction followed by
a plantar flexion maneuver. In these cases, open reduction is performed through a dorsomedial incision through which the tibialis posterior is retracted medially, allowing reduction of the talonavicular joint. The joints usually require pinning to maintain stability during healing. The long-term prognosis for these injuries is guarded because many patients develop degenerative changes in the Chopart joint. If symptomatic arthritis develops, helpful external supports are designed to limit sagittal motion at the joint (for example, carbon fiber inserts or rocker-bottom soles).
RECOMMENDED READINGS
Swords MP, Schramski M, Switzer K, Nemec S. Chopart fractures and dislocations. Foot Ankle Clin. 2008 Dec;13(4):679-93, viii. Doi: 10.1016/j.fcl.2008.08.004. Review. PubMed PMID: 19013402.View Abstract at PubMed
Richter M, Thermann H, Huefner T, Schmidt U, Goesling T, Krettek C. Chopart joint fracture-dislocation: initial open reduction provides better outcome than closed reduction. Foot Ankle Int. 2004 May;25(5):340-8. PubMed PMID: 15134617. View Abstract at PubMed

Question 38

Figures 1 and 2 depict the postoperative radiographs obtained from a 22-year-old man who was involved in a motor vehicle accident. The most likely limitation in motion arising from this treatment is

Explanation

EXPLANATION:
This patient sustained fractures of his radius and ulna; both were treated with plate and screw fixation. The plate used on the radius was straight, resulting in loss of the radial bow, which is critical for enabling the radius to curve around the ulna during pronation. This patient is unable to pronate beyond 20°. Schemitsch and Richards correlated a good functional outcome, defined as more than 80% of normal rotation of the forearm, with restoration of the normal amount and location of the radial bow. Additionally, they related the restoration of grip strength with appropriate restoration of the radial bow. Matthews and associates reported little significant loss of rotation with 10° of angulation; however, 20° of angulation resulted in a statistically and clinically significant loss of forearm rotation.

Question 39

Figures 1 and 2 are the right shoulder MRI scans of a 22-year-old right-handed professional male volleyball player with 4 months of right shoulder pain. The pain began insidiously and is exacerbated by overhead activities and hitting during games. He has maintained a daily program of shoulder stretching and strengthening exercises but has experienced a steady decline in function to the point of not being able to participate in volleyball. Examination reveals some mild atrophy at the posterior shoulder, full forward elevation, mild weakness of external rotation on the right shoulder, negative empty-can testing, positive O’Brien’s and negative apprehension. Surgical intervention would aim to resolve pathology related to which nerve?

Explanation

This athlete has a symptomatic posterior-superior labral tear, spinoglenoid notch cysts, and subsequent suprascapular nerve compression, as evidenced by the atrophy of the infraspinatus muscle on sagittal T1 MRI. The cyst is located at the spinoglenoid notch and is compressing the suprascapular nerve after it has innervated the supraspinatus but before innervation of the infraspinatus; hence, the atrophy of infraspinatus on examination and imaging. Compression of the suprascapular nerve at the suprascapular notch would lead to weakness and atrophy of both the supraspinatus and infraspinatus. The lower subscapular nerve innervates the teres major, as well as, with the upper subscapular nerve, the subscapularis. The teres minor is innervated by the axillary nerve.

Question 40

Overgrowth of a limb in a patient with neurofibromatosis type 1 (NF1) is most likely associated with the presence of

Explanation

DISCUSSION: Plexiform neurofibromas are lesions found in patients with NF1. Clinical reports show the prevalence of plexiform neurofibroma to be 20% to 30% but increases to 40% when imaging studies are routinely obtained. The lesions are characterized by diffuse hypertrophy of the involved nerves but with preservation of the nerves’ fascicular organization. The lesions may involve the dermis or may arise in the deeper structures. Palpation of a dermal lesion provokes an image of a “bag of worms.” Plexiform neurofibromas may cause disfigurement and hyperpigmentation of the overlying skin. The lesions also can cause diffuse hypertrophy of the soft tissue and bone, with resultant changes ranging from a relatively minor limb-length discrepancy to gigantism of the entire extremity. Dural ectasia is frequently found in patients with NF1. Therefore, MRI should be obtained prior to planning spinal procedures in these patients; however, dural ectasia is not the cause of limb overgrowth. Lisch nodules are benign hamartomas of the iris. The lesions are uncommon during early childhood but are found in all adults with NF1. Juvenile xanthogranuloma has a low occurrence rate in patients with NF1; its presence is associated with juvenile chronic myeloid leukemia. Malignant peripheral nerve sheath tumors, formally called neurofibrosarcoma, result from malignant degeneration of a plexiform neurofibroma. This condition occurs in up to 4% of patients with NF1. Localized pain, an enlarging mass, or progressive neurologic symptoms suggest a malignant peripheral nerve sheath tumor in a patient with NF1. However, progressive neurologic symptoms also may occur with benign growth of a plexiform neurofibroma.
REFERENCES: Alman BA, Goldberg MJ: Syndromes of orthopaedic importance, in Morrissy RT, Weinstein SL (eds): Lovell and Winter’s Pediatric Orthopaedics, ed 5. Philadelphia, PA, Lippincott Williams and Wilkins, 2001, pp 287-338.
Greene WB: Neurofibromatosis type I, in Fitzgerald RH, Kaufer H, Malkani AL (eds): Orthopaedics. St Louis, MO, Mosby, 2002, pp 1584-1588.

Question 41

A 17-year-old high school soccer player sustains an anterior cruciate ligament (ACL) tear at the beginning of the season. An MRI scan confirms a complete ACL tear with no meniscal injuries. The patient plans an early return to play and would like to avoid surgery. Therefore, the patient and family should be advised that nonsurgical management consisting of rehabilitative exercises and the use of a functional knee brace will most likely result in

Explanation

DISCUSSION: While there are athletes who can function at a full level with an ACL tear, they are in the minority. As yet, there is no reliable way to predict the patients who will be able to compensate for the loss of the ACL. Studies have confirmed the risk of recurrent instability and meniscal injury in athletes with an ACL-deficient knee who participate in cutting sports. One study showed that only 12 of 43 patients who attempted rehabilitation and bracing were able to return successfully for the season. Another study showed that 17 of 31 athletes who were able to return to their sport sustained 23 meniscal tears because of recurrent instability.
REFERENCES: Shelton WR, Barrett GR, Dukes A: Early season anterior cruciate ligament tears: A treatment dilemma. Am J Sports Med 1997;25:656-658.
Snyder-Mackler L, Fitzgerald GK, Bartolozzi AR III, Ciccotti MG: The relationship between passive joint laxity and functional outcome after anterior cruciate ligament injury. Am J Sports Med 1997;25:191-195.

Question 42

A patient has a noncomminuted displaced fracture of the radial head with a distal radioulnar dissociation. What is the most appropriate treatment for the radial head?

Explanation

This is a rare injury, and it is important to recognize both the proximal and distal concurrent injuries. In the past, the radial head excision has been the primary form of treatment, but this has shown poor long-term results; silicone replacement has been fraught with reactive synovitis. Radial ulnar synostosis is a complication, not a planned course of treatment.

Question 43

Figure 33 shows the CT scan of a 40-year-old man who injured his left shoulder while skiing. What structure is attached to the bony fragment?

Explanation

DISCUSSION: The scan reveals a bony Bankart lesion. The anterior band of the inferior glenohumeral ligament is the major restraint to anterior translation of the humeral head and is usually injured with anterior shoulder dislocations. It inserts onto the glenoid labrum at the anteroinferior aspect of the glenoid rim. The labrum most frequently avulses from the glenoid (Bankart lesion), but occasionally the bony attachment is avulsed.
REFERENCES: O’Brien SJ, Neves MC, Arnoczky SP, et al: The anatomy and histology of the inferior glenohumeral ligament complex of the shoulder. Am J Sports Med 1990;18:449-456.
Warner JP: The gross anatomy of the joint surfaces, ligaments, labrum and capsule, in Matsen FA, Fu FF, Hawkins RJ (eds): The Shoulder: A Balance of Mobility and Stability. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1992, pp 7-28.

Question 44

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

Explanation

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

Question 45

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

Explanation

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

Question 46

Figures 20a and 20b show the sagittal and coronal T1-weighted MRI scans of a patient’s left knee. Abnormal findings include

Explanation

DISCUSSION: The MRI scans show meniscal tissue extending across the entire lateral compartment, revealing a discoid lateral meniscus. The increased signal within the lateral meniscal tissue indicates a tear. Discoid lateral menisci are congenital variants that often present with mechanical symptoms in adolescents. The other structures in the knee are normal.
REFERENCES: Ahn JH, Shim JS, Hwang CH, et al: Discoid lateral meniscus in children: Clinical manifestations and morphology. J Pediatr Orthop 2001;21:812-816.
Andrish JT: Meniscal injuries in children and adolescents: Diagnosis and management.

J Am Acad Orthop Surg 1996;4:231-237.

Question 47

A 56-year-old man underwent right total shoulder arthroplasty 2 months ago. Recently while reaching with his shoulder in a flexed and adducted position, he noted shoulder pain and afterwards he could not externally rotate his arm. An axillary radiograph is shown in Figure 30. What is the most likely cause of this problem?

Explanation

DISCUSSION: Anteversion of the humeral component may result in anterior instability of the component. Posterior instability after total shoulder arthroplasty is usually the result of some combination of the following factors: untreated anterior soft-tissue contractures, excessive posterior capsular laxity, and excessive retroversion of the humeral and/or glenoid components.
REFERENCES: Cofield RH, Edgerton BC: Total shoulder arthroplasty: Complications and revision surgery. Instr Course Lect 1990;39:449-462.
Wirth MA, Rockwood CA Jr: Complications of total shoulder replacement arthroplasty. J Bone Joint Surg Am 1996;78:603-616.

Question 48

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

Explanation

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

Question 49

-A likely candidate for treatment with a thoracic lumbosacral orthosis scoliosis brace is seen in

Explanation

Question 50

A 7-year-old boy sustains an acute injury to the distal radial metaphysis, along with a completely displaced Salter-Harris type I fracture of the ulnar physis, as shown by the arrows in Figure 12. After satisfactory reduction of both injuries, what is the major concern?

Explanation

DISCUSSION: While injury of the distal radial metaphysis is a rather common occurrence, the incidence of physeal arrest is only about 4% to 5% of patients. While injury of the distal physis of the ulna is rare, the incidence of physeal arrest is greater than 50% in fractures of this structure. These patients need to be followed closely both clinically and radiographically to look for the signs of distal ulnar/physeal arrest such as loss of the prominence of the ulna and ulnar deviation of the hand. Radiographically, progressive shortening of the ulna is observed.
REFERENCES: Nelson OA, Buchanan JR, Harrison CS: Distal ulnar growth arrest. J Hand Surg Am 1984;9:164-170.
Ogden JA: Skeletal Injury in the Child. New York, NY, Springer-Verlag, 2000, pp 632-635.

Question 51

Flexion-distraction injuries of the thoracolumbar spine are most frequently associated with injury to what organ system?

Explanation

DISCUSSION: In patients with flexion-distraction injuries of the thoracolumbar spine, 50% have associated, potentially life-threatening, visceral injuries that occasionally are diagnosed hours or even days after admission. Based on these findings, consultation with a general surgeon is recommended. Blunt and penetrating injuries to the cardiopulmonary system or aorta sometimes can be seen with this type of injury, but they are no more common than with other types of thoracolumbar fractures because of the relatively mild bony injury anteriorly. Neurologic trauma with this type of fracture is also somewhat rare.
REFERENCES: Levine AM (ed): Orthopaedic Knowledge Update: Trauma. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1996, pp 351-360.
Inaba K, Kirkpatrick AW, Finkelstein J, et al: Blunt abdominal aortic trauma in association with thoracolumbar spine fractures. Injury 2001;32:201-207.

Question 52

Figure 29 shows the radiograph of a 25-year-old woman who has had a 3-month history of ankle pain after sustaining an inversion injury to the ankle. She reports occasional catching, but no sense of instability. Examination reveals ligament stability. Management should consist of

Explanation

DISCUSSION: Osteochondral lesions of the talar dome can have a traumatic or nontraumatic etiology. Most authors site a probable traumatic etiology for lateral lesions. Stage I and II lesions, which are composed of compressed subchondral bone or a partial detached osteochondral fragment, can be treated initially in a non-weight-bearing short leg cast for 6 weeks. Stage III medial lesions can also be treated in the same manner. If symptoms persist, the treament of choice is debridement of the fracture, curettage of the lesion, and drilling of the subchondral bone. This treatment also applies to lateral stage III and all stage IV lesions. If the fragment is at least one third of the size of the talar dome, management should consist of open reduction and internal fixation. In patients with more chronic lesions (4 to 6 months of persistent pain), the threshold to proceed with surgery is lower, even in a stage II lesion.
REFERENCES: Lutter LD, Mizel MS, Pfeffer GB (eds): Orthopaedic Knowledge Update: Foot and Ankle. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1994, pp 205-226.
Pettine KA, Morrey BF: Osteochondral fractures of the talus: A long-term follow-up. J Bone Joint Surg Br 1987;69:89-92.

Question 53

An osteoconductive bone graft material has which of the following properties?

Explanation

Osteoconductive bone graft material is described as the scaffold that allows new bone growth. This new bone is created via sprouting capillaries, perivascular tissue, and osteoprogenitor cells on the three-dimensional graft structure, permitting creeping
substitution, which allows for graft incorporation. An osteoinductive graft will stimulate the recruitment of progenitor cells that can differentiate into osteoblastic cells. Specific BMPs are osteoinductive. Osteogenic material contains viable cells with the ability to form bone. The ability to provide osteoprogenitor cells is only seen in fresh autograft. Other grafts rely on the recruitment of host progenitor cells to differentiate.

Question 54

The radiograph shown in Figure 27 shows measurement of what angle?

Explanation

DISCUSSION: The relationship between the distal articular surface of the first metatarsal head and the long axis of the first metatarsal is called the distal metatarsal articular angle. This angle has been validated by Richardson and associates to measure and determine the congruence of the first metatarsophalangeal joint. This angle is critical in determining the appropriate surgical procedure to perform on a patient with a bunion deformity because a congruent joint requires a procedure to maintain congruence of the articular surfaces following osteotomy. Therefore, a chevron becomes a biplanar chevron, and a Lapidus procedure adds a second osteotomy of the distal metatarsal to tilt the metatarsal head into a congruent location.
REFERENCES: Coughlin MJ: Juvenile hallux valgus: Etiology and treatment. Foot Ankle Int 1995;16:682-697.
Steel MW III, Johnson KA, DeWitz MA, et al: Radiographic measurements of the normal foot. Foot Ankle 1980;1:151-158.
Richardson EG, Graves SC, McClure JT, et al: First metatarsal head-shaft angle: A method of determination. Foot Ankle 1993;14:181-185.

Question 55

What nerve is most at risk during placement of the anterolateral portal in elbow arthroscopy?

Explanation

DISCUSSION: The radial nerve is only 4 mm from the anterolateral portal, while the median nerve is 11 mm away from the anteromedial portal. The ulnar nerve is only at risk on the medial side of the elbow. Anterior and posterior interosseous nerves are more distal within the forearm and are not in danger during portal placement.
REFERENCES: O’Driscoll SW, Morrey BF: Elbow arthroscopy, in Morrey BF (ed): The Elbow. Philadelphia, PA, Lippincott, Williams and Wilkins, 1994, pp 21-34.
Field LD, Altchek DW, Warren RF, O’Brien SJ, Skyhar MJ, Wickiewicz TL: Arthroscopic anatomy of the lateral elbow: A comparison of three portals. Arthroscopy 1994;10:602-607.

Question 56

A 12-year-old girl has back pain after falling 20 feet and landing in the sitting position. She has no fractures or other injuries, and her neurologic examination is normal. A lateral radiograph, transverse CT scan, and reformatted sagittal CT scan are shown in Figures 25a through 25c. Which of the following methods is associated with the best long-term outcome?

Explanation

DISCUSSION: The patient has a displaced burst fracture. Fusion with instrumentation has shown better results than casting alone. Posterior fusion with instrumentation, with sagittal plane correction, yields the best results. Decompression occurs indirectly with correction of the kyphosis. Anterior decompression is unnecessary.
REFERENCES: Lalonde F, Letts M, Yang JP, et al: An analysis of burst fractures of the spine in adolescents. Am J Orthop 2001;30:115-120.
Clark P, Letts M: Trauma to the thoracic and lumbar spine in the adolescent. Can J Surg 2001;44:337-345.
Been HD, Bouma GJ: Comparison of two types of surgery for thoraco-lumbar burst fractures: Combined anterior and posterior stabilization vs posterior instrumentation only. Acta Neurochir (Wien) 1999;141:349-357.

Question 57

A 35-year-old man has numbness and tingling in the index, middle, and ring fingers. History reveals that he also has had vague wrist pain and stiffness since being injured in a motorcycle accident 1 year ago. Radiographs are shown in Figures 47a through 47c. Management should consist of

Explanation

DISCUSSION: The patient has a chronic unrecognized volar lunate dislocation. Median nerve compression is the result of the lunate displaced into the carpal tunnel. The diagnosis can be made by radiographs; MRI is not necessary. A volar approach allows median nerve decompression with excision of the lunate, whereas a dorsal approach facilitates excision of the scaphoid and triquetrum.
REFERENCES: Rettig ME, Raskin KB: Long-term assessment of proximal row carpectomy for chronic perilunate dislocations. J Hand Surg Am 1999;24:1231-1236.
Howard FM, Dell PC: The unreduced carpal dislocation: A method of treatment. Clin Orthop 1986;202:112-116.

Question 58

Osteoclastic bone resorption is stimulated primarily by what molecular interaction?

Explanation

OPG is a receptor that competitively binds with RANKL, blocking the interaction with RANK and inhibiting osteoclastogenesis. PTH, secreted by the chief cells of the parathyroid gland, is active in calcium homeostasis independent of inflammatory arthropathies. PTH increases serum calcium indirectly by binding to osteoblasts, increasing expression of RANKL and decreasing expression of OPG. The interaction of RANKL to RANK in turn stimulates osteoclast precursors to fuse, forming
osteoclasts to enhance bone resorption. The pannus of rheumatoid arthritis and monosodium urate crystals of gouty tophi have been shown to trigger release of inflammatory cytokines such as IL-6, IL-8 and tumor necrosis factor alpha. The key to osteoclastic bone resorption of inflammatory arthropathy is regulated by the interaction of RANKL, expressed in osteoblasts and activated T cells, and RANK, expressed in osteoclast progenitors and mature osteoclasts. In inflammatory arthropathy, RANKL expression is increased and OPG is reduced, resulting in increased cortical and subchondral bone.

Question 59

A 10-year-old girl with a history of an obstetrical brachial plexus palsy has been referred for evaluation. Examination reveals a severe adduction internal rotation contracture of the shoulder and a mild flexion contracture of the elbow. Hand function is normal. Radiographs show mild glenohumeral joint incongruity. To achieve the best functional outcome, management should consist of

Explanation

DISCUSSION: The patient has an upper plexus palsy (Erb palsy) with severe shoulder contracture. While physical therapy for stretching is the treatment of choice to prevent contracture in the newborn, it is unlikely to be of benefit in the older child with an established contracture. Contracture release alone or in combination with muscle transfers can improve the cosmetic appearance, and in the case of a mild deformity, may also improve function. These procedures are less likely to help when there is deformity of the shoulder joint or when arthritic changes are present. The procedure of choice for an older child with joint deformity is rotational osteotomy of the proximal humerus because it can improve cosmesis and function, even in the face of joint deformity.
REFERENCES: Jahnke AH Jr, Bovill DF, McCarroll HR Jr, James P, Ashley RK: Persistent brachial plexus birth palsies. J Pediatr Orthop 1991;11:533-537.
Strecker WB, McAllister JW, Manske PR, Schoenecker PL, Dailey LA: Sever-L’Episcopo transfers in obstetrical palsy: A retrospective review of 20 cases. J Pediatr Orthop 1990;10:442-444.
Goddard NJ, Fixsen JA: Rotation osteotomy of the humerus for birth injuries of the brachial plexus. J Bone Joint Surg Br 1984;66:257-259.

Question 60

Which of the following surgical approaches to the hip is associated with the highest incidence of heterotopic ossification?

Explanation

Significant extopic bone formation results from a combination of initial trauma to the gluteal muscle mass and surgical exposure of the lateral surface of the pelvis. Extensile (extended iliofemoral or triradiate) approaches are associated with the highest incidence of ectopic bone formation, whereas the ilioinguinal approach is rarely associated with this complication. Many of the fractures described in this chapter require a posterolateral or extensile approach in order to achieve acceptable fracture reduction. When these approaches must be used, local measures may be helpful in reducing the incidence of heterotopic ossification. Debridement of devitalized muscle, particularly the gluteus minimus, has been shown to limit the extent of ectopic bone formation.
Prevention:
incision choice: ilioinguinal if possible
radiation
indocin (give pepcid with it)

Question 61

A 19-year-old soccer player feels a pop in his knee while making a cut and notes the development of an effusion over several hours. Examination reveals medial joint line tenderness, but the knee is stable to manual stress testing of all ligaments. Examination under anesthesia confirms a stable knee. What is the most critical factor in determining healing after repair of the lesion shown in Figure 14?

Explanation

DISCUSSION: Numerous clinical and basic science investigations have evaluated meniscal tear characteristics to identify factors that either promote or mitigate against meniscal healing. Complex tears have been noted to heal poorly, while longitudinal tears heal more predictably. Tear length, time from injury to repair, medial versus lateral meniscal tears, and the use of a fibrin clot have not been shown to consistently affect meniscal healing. However, rim width, the distance of the tear site from the peripheral meniscocapsular junction (vascular supply), has been shown to have a significant role in the ability of a meniscus repair to heal.
REFERENCES: DeHaven KE, Arnoczky SP: Meniscus repair: Basic science, indications for repair, and open repair. Instr Course Lect 1994;43:65-76.
Henning CE, Lynch MA, Clark JR: Vascularity for healing of meniscus repairs. Arthroscopy 1987;3:13-18.

Question 62

CLINICAL SITUATION Figures 1 and 2 are the radiographs of a 68-year-old woman who comes to the emergency department after stepping into a hole and twisting her ankle. She is complaining of isolated ankle pain and is unable to bear weight. After closed manipulative reduction and splint placement, she is scheduled for operative treatment. The stability of the syndesmosis should be evaluated after

Explanation

Discussion: The radiographs reveal a trimalleolar ankle fracture dislocation with an associated distal tibiofibular syndesmotic disruption. Medial and lateral malleolar stabilization are consistently agreed upon. The decision to stabilize the posterior malleolus is more controversial. Posterior malleolar stabilization accomplishes the following:
Restores incisura competence thereby reducing the incidence of syndesmotic malreduction by creating containment
Assists in stabilizing the syndesmosis via the posterior inferior tibiofibular ligament, potentially limiting the need for additional syndesmotic stabilization
Maximizes the surface area for ankle joint loading
Enhances posterior translational stability of the talus
The traditional indication for stabilization of the posterior malleolus is based on fragment size. However, fracture orientation varies and makes evaluation of the fragment size challenging with a lateral radiograph alone. The three primary types include the posterolateral oblique, medial extension, and shell. Because of the additive syndesmotic stability which is gained through the deep deltoid ligament and medial malleolar fixation, the anterior talofibular ligament and lateral malleolar fixation, and the posterior inferior tibiofibular ligament and posterior malleolar fixation, syndesmotic stability should only be assessed after all other points of instability that are planned for fixation are fixed.
Syndesmotic instability should be assessed with direct manipulation on both the anteroposterior and lateral views with special attention to the lateral view. Syndesmotic reduction should be assessed either through open visualization or by comparing closed reduction parameters (clear space, overlap, and fibular position on the lateral view) with the patient’s contralateral side (assuming no injury). This is more effective than using population norms secondary to the two types of syndesmotic morphologies which create different absolute values for these parameters.

Question 63

What is the main function of collagen found within articular cartilage?

Explanation

DISCUSSION: The main function of collagen in articular cartilage is to provide the tissue’s tensile strength. It also immobilizes proteoglycans within the extracellular matrix. Compressive properties are maintained by proteoglycans. Cartilage metabolism is maintained by the indwelling chondrocytes. The flow of water through the tissue promotes transport of nutrients and provides a source of lubricant for the joint.
REFERENCES: Simon SR (ed): Orthopaedic Basic Science. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1994, pp 3-44.
Mow VC, Ratcliffe A: Structure and function of articular cartilage and meniscus, in Mow VC, Hayes WC (eds): Basic Orthopaedic Biomechanics, ed 2. Philadelphia, PA, Lippincott-Raven, 1997, pp 113-177.

Question 64

Surgical restoration of sagittal balance of an adult spinal deformity will have which effect on outcome?

Explanation

DISCUSSION
The influence of sagittal balance on outcomes following fusion-based procedures for degenerative conditions of the lumbar spine has only recently been appreciated. Restoration of sagittal spinal balance improves low-back-pain outcomes and quality of life. Sagittal spinal balance has not been shown to relieve neurogenic claudication attributable to spinal stenosis.
RECOMMENDED READINGS
Li Y, Hresko MT. Radiographic analysis of spondylolisthesis and sagittal spinopelvic deformity. J Am Acad Orthop Surg. 2012 Apr;20(4):194-205. doi: 10.5435/JAAOS-20-04-194. Review. PubMed PMID: 22474089. View Abstract at PubMed
Korovessis P, Repantis T, Papazisis Z, Iliopoulos P. Effect of sagittal spinal balance, levels of posterior instrumentation, and length of follow-up on low back pain in patients undergoing posterior decompression and instrumented fusion for degenerative lumbar spine disease: a multifactorial analysis. Spine (Phila Pa 1976). 2010 Apr 15;35(8):898-905. doi: 10.1097/BRS.0b013e3181d51e84. PubMed PMID: 20354466. View Abstract at PubMed
CLINICAL SITUATION FOR QUESTIONS 99 AND 100
Figures 99a and 99b are MR images of a 59-year-old man with a history of intravenous (IV) drug abuse who arrives at the emergency department with malaise and fever. Upon admission, the patient's temperature is 38.9°C, his white blood cell count is 17000/µL (reference range [rr], 4500-11000/µL), his erythrocyte sedimentation rate is 98 mm/h (rr, 0-20 mm/h), and his C-reactive protein level is 45 mg/L (rr, 0.08-3.1 mg/L). He is admitted to the medical service to evaluate the source of his fevers. On hospital day 1, the patient reports weakness in his left arm and leg. Blood cultures are positive for methicillin-resistant Staphylococcus aureus.

A B

Question 65

To avoid damage to the ascending branch of the anterior humeral circumflex artery during open reduction and internal fixation of a proximal humeral fracture, the blade plate should be placed in what position?

Explanation

DISCUSSION: The pectoralis major tendon inserts lateral to the biceps tendon, which runs in the bicipital groove. The primary vascular supply of the articular surface of the humeral head is derived from the anterior circumflex humeral artery, which continues into the arcuate artery once it enters the bone. The entry point is on the anterolateral aspect of the humerus just medial to the greater tuberosity within the bicipital groove. To avoid compromising circulation, the blade plate should be placed lateral to the bicipital groove and pectoralis major tendon insertion.
REFERENCES: Loebenberg M, Plate AM, Zuckerman J: Osteonecrosis of the humeral head. Instr Course Lect 1999;48:349-357.
Gerber C, Schneeberger AG: The arterial vascularization of the humeral head: An anatomical study. J Bone Joint Surg Am 1990;72:1486-1494.

Question 66

Compared with retention of the native patella in primary total knee arthroplasty, routine patellar resurfacing is associated with

Explanation

DISCUSSION:
Despite concerns regarding fracture, osteonecrosis, and patellar clunk, the routine retention of the native patella during primary total knee replacement is associated with a 20% to 30% increased revision risk in
large joint registries. In addition, the retention of the native patella results in a 5.7% revision surgery rate
in patients with anterior knee pain.

Question 67

A 14-year-old boy is seen for back pain. Radiographic evaluation reveals a grade III isthmic spondylolisthesis. What measurement is most useful in predicting the likelihood of progression? Review Topic

Explanation

Slip angle has been shown to be highly predictive of the risk for increased slippage in patients with spondylolisthesis. None of the other radiographic parameters listed has been shown to be predictive of the risk for increased slippage.

Question 68

A subtrochanteric femur fracture in which the lesser trochanter is intact is associated with what deformity?

Explanation

The most commonly seen deformity in subtrochanteric femur fractures is abduction and flexion of the proximal fragment. Subtrochanteric fractures can pose challenges in reduction because of the muscle attachments proximal and distal to the fragment. The gluteus medius and gluteus minimus attach to the greater trochanter and abduct the proximal fragment. The iliopsoas attaches to the lesser trochanter, flexing and externally rotating the proximal fragment. The short external rotators (piriformis, superior and inferior gamellus) and the obturator internus also cause external rotation of the proximal fragment.

Question 69

A B Figures 19a and 19b are the CT scans of an 18-year-old man who was a restrained driver in a rollover motor vehicle collision. What was the primary mechanism of injury?

Explanation

DISCUSSION
This injury pattern represents a flexion distraction injury, or a Chance fracture. The imaging hallmark of this injury is the axial split of the pedicle seen on the sagittal CT scan. This injury necessitates surgical intervention to prevent progressive deformity and pain. A rotation mechanism results in a dislocation with a rotational deformity at the level of injury. An extension force causes failure of the anterior column in tension with compression of the posterior column. An axial load force would result in a burst fracture.
RECOMMENDED READINGS
Bono CM, Rinaldi MD. Thoracolumbar trauma. In: Spivak JM, Connolly PJ, eds. Orthopaedic Knowledge Update: Spine 3. Rosemont, IL: American Academy of Orthopaedic Surgeons; 2006:201-216.
Vaccaro AR, Baron EM, Sanfilippo J, Jacoby S, Steuve J, Grossman E, DiPaola M, Ranier P, Austin L, Ropiak R, Ciminello M, Okafor C, Eichenbaum M, Rapuri V, Smith E, Orozco F, Ugolini P, Fletcher M, Minnich J, Goldberg G, Wilsey J, Lee JY, Lim MR, Burns A, Marino R, DiPaola C, Zeiller L, Zeiler SC, Harrop J, Anderson DG, Albert TJ, Hilibrand AS. Reliability of a novel classification system for thoracolumbar injuries: the Thoracolumbar Injury Severity Score. Spine (Phila Pa 1976). 2006 May 15;31(11 Suppl):S62-9; discussion S104. PubMed PMID:16685239.View Abstract at PubMed

Question 70

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 71

A 28-year-old painter has had increasing pain in his hand and forearm after sustaining a paint injection wound to the tip of his left index finger 24 hours ago. Management should consist of

Explanation

DISCUSSION: The clinical presentation soon after injury may be surprisingly innocuous, but all high-pressure injection injuries of various materials are best treated by emergent surgical debridement of all foreign material from the flexor tendon sheath as well as the subcutaneous tissues. Subsequent hospital admission, IV antibiotics, and possible repeat debridements usually are necessary. The use of antibiotics alone is inadequate treatment of this severe injury.
REFERENCES: Pinto MR, Turkula-Pinto LE, Cooney WP, Wood MB, Dobyns JH: High-pressure injection injuries of the hand: Review of 25 patients managed by open wound technique. J Hand Surg Am 1993;18:125-130.
Urbaniak JR, Evans JP, Bright DS: Microvascular management of ring avulsion injuries. J Hand Surg Am 1981;6:25-30.
Tsai TM, Manstein C, DuBou R, Wolff T, Kutz JE, Kleinert HE: Primary microsurgical repair of ring avulsion amputation injuries. J Hand Surg Am 1984;9:68-72.
Kay S, Werntz J, Wolff T: Ring avulsion injuries: Classification and prognosis. J Hand Surg Am 1989;14:204-213.
Schnall SB, Mirzayan R: High-pressure injection injuries to the hand, in Kozin SH (ed): Hand Clinics: Upper Extremity Trauma. Philadelphia, PA, 1999, pp 245-248.

Question 72

A 25-year-old male professional lacrosse player collides with another player, with injury resulting from a knee impacting the athlete’s thigh. He has immediate pain in the mid-thigh area and is unable to return to the game because of difficulty with running. Examination reveals developing swelling in the anterior mid-thigh area. The thigh compartments are soft, and he is able to extend his knee against gravity. Knee flexion at 90° gives him discomfort in the thigh but no knee pain. The knee and hip examinations are otherwise unremarkable. Plain films of the femur are negative. What is the best next step?

Explanation

The lesion seen in the MRI scan in Figure 1 is treated with a marrow stimulation technique. The reparative tissue formed by this technique is predominantly composed of
A. only type 1 collagen.
B. only type 2 collagen.
C. type 1 and type 2 collagen.
D. neither type 1 or type 2 collagen.
The MRI scan shows a full-thickness cartilage defect. When treated with a marrow stimulation technique, such as a microfracture, the reparative tissue is fibrocartilage. Unlike hyaline cartilage, which is composed of only type 2 collagen, fibrocartilage is composed of both type 1 and type 2 collagen.
15- Figures 1 and 2 are the radiographs of a 58-year-old retired laborer who has had many years of right shoulder pain. He initially experienced relief with anti-inflammatory medication over the past year, but this no longer provides him pain relief. He has pain with overhead activities and is dissatisfied with his shoulder function. Examination indicates active and passive forward elevation to 130°, full strength with external rotation, and a negative belly press test. MRI demonstrates an intact rotator cuff. What is the best next step in treatment?
A. Anatomic total shoulder arthroplasty (TSA)
B. Hemiarthroplasty
C. Reverse shoulder arthroplasty
D. Arthroscopy with debridement and biceps tenodesis
The patient has glenohumeral osteoarthritis based on the radiograph. His examination demonstrates limited motion and no significant rotator cuff pathology – full strength with external rotation, negative belly press, and no pseudoparalysis. Of all the answer choices, an anatomic TSA would be the most appropriate treatment option. Hemiarthroplasty does not address glenoid pathology and provides inferior pain relief and function, compared with TSA. A reverse shoulder arthroplasty is utilized for patients with degenerative shoulder changes in conjunction with irreparable rotator cuff pathology. Shoulder arthroscopy with debridement and biceps tenodesis is not appropriate for those with severe degenerative changes of the shoulder.
16- According to the MRI scan shown in Figure 1, which pathologic finding is expected to be encountered during arthroscopy?
A. Figure 2
B. Figure 3
C. Figure 4
D. Figure 5
The sagittal MRI scan is a clear example of a double posterior cruciate ligament (PCL) sign. This sign has a high specificity for a displaced bucket handle tear of the medial meniscus as seen in Figure 4. The other arthroscopic
images show a flap tear of the medial meniscus (Figure 2), anterior cruciate ligament tear (Figure 3), and a full thickness articular cartilage defect (Figure 5). Other less likely causes of a double PCL sign include intermeniscal ligament, meniscofemoral ligaments, loose bodies, osteophytes, and fracture fragments. Correct answer : C 13
17- Figures 1 and 2 are the radiographs of a 21-year-old football player who underwent anterior cruciate ligament (ACL) reconstruction with patellar tendon autograft 1 year ago. He reports mild stiffness in his knee. Upon examination, he has a negative Lachman test, trace effusion, and range of motion from 0 to 85° of knee flexion. Which factor is most contributory to his examination findings?
A. Incorrect graft choice
B. Improper tunnel position
C. Tibial graft-tunnel mismatch
D. Femoral fixation at 80° flexion
Technical failure is the most common reason for ACL reconstruction failure. Tunnel position is the most frequent cause of technical failure. Malpositioning of the tunnel affects the length of the graft, causing either decreased range of motion or increased graft laxity. This patient has anterior and vertical placement of his femoral tunnel, which has been shown to cause stiffness in knee flexion. Although graft choice is an important factor when planning ACL reconstruction, overall outcomes with autograft tissues are fairly similar. Fixation of the graft at the femoral or tibial end is not as important as tunnel position. Fixing the graft in flexion can cause extension loss when isometry is not achieved, but this condition is not touched upon in this scenario.

Question 73

A 16-year-old male fell from a roof onto his right shoulder and presents with decreased pulses in his right upper extremity. Imaging reveals a posterior sternoclavicular dislocation. What is the best treatment at this time?

Explanation

DISCUSSION: Symptomatic acute posterior sternoclavicular dislocations in adolescents should undergo open reduction and ligament (costoclavicular) reconstruction with thoracic surgery back-up. In patients younger than age 20-25, this is usually a physeal injury, as the medial clavicular physis does not close until this age range. Chronic anterior or posterior dislocations are recommended to be treated conservatively, especially if not symptomatic.
The review article by Wirth and Rockwood notes the following complications with posterior dislocation: respiratory distress, venous congestion or arterial insufficiency, brachial plexus compression, and myocardial conduction abnormalities. They recommend reconstruction of the costoclavicular ligaments with resection of the medial clavicular head as needed for unstable injuries.
The referenced article by Waters et al noted 100% excellent short-term outcomes in adolescents with open reduction and reconstruction of the costoclavicular ligament in pure dislocations or with suture fixation of the medial physis in physeal injuries.

Question 74

Figures 42a and 42b show the radiographs of a 52-year-old man who sustained a fall from a motorcycle 6 months ago and now reports pain and stiffness in his left shoulder. What is the most reliable treatment to improve function and comfort of the shoulder?

Explanation

DISCUSSION: Appropriate treatment is based on multiple considerations, which include the chronicity of the dislocation, the amount of humeral head involvement, the medical condition, and functional limitations of the patient. It has been shown that shoulder arthroplasty for locked posterior dislocation provides pain relief and improved motion. Transfer of the lesser tuberosity with its attached subscapularis tendon into the defect is recommended for anteromedial humeral defects that are smaller than approximately 40% of the joint surface. Subscapularis transfer as described by McLaughlin and the modification thereof later described by Hawkins and associates in which the lesser tuberosity is transferred into the defect, have yielded good results if the defect is less than 40% of the humeral head. Prosthetic replacement is preferred for larger defects. If the dislocation is less than 3 weeks old and has less than 25% of humeral head involvement, closed reduction with the patient under general anesthesia should be attempted and the stability assessed by internally rotating the arm. If the arm can be safely internally rotated to the abdomen, then 6 weeks of immobilization in an orthosis that maintains the shoulder in slight extension and external rotation can yield a good result. If the dislocation has been present for more than 3 weeks, closed reduction becomes exceedingly difficult.
REFERENCES: Gerber C, Lambert SM: Allograft reconstruction of segmental defects of the humeral head for the treatment of chronic locked posterior dislocation of the shoulder. J Bone Joint Surg Am 1996;78:376-382.
Spencer EE Jr, Brems JJ: A simple technique for management of locked posterior shoulder dislocations: Report of two cases. J Shoulder Elbow Surg 2005;14:650-652.
Sperling JW, Pring M, Antuna SA, et al: Shoulder arthroplasty for locked posterior dislocation of the shoulder. J Shoulder Elbow Surg 2004;13:522-527.
Hawkins RJ, Neer CS II, Pianta RM, et al: Locked posterior dislocation of the shoulder. J Bone Joint Surg Am 1987;69:9-18.
McLaughlin HL: Posterior dislocation of the shoulder. J Bone Joint Surg Am 1952;34:584-590.

Question 75

A 45-year-old woman with grade II adult-acquired flatfoot deformity has pain on the lateral side of her foot just distal to the tip of the fibula. Which component of a comprehensive flatfoot reconstruction most likely will address the deformity responsible for this pain?

Explanation

DISCUSSION
Patients develop lateral ankle pain with progression of adult-acquired flatfoot deformity. This is associated with increased hindfoot valgus deformity. Calcaneal fibular impingement has been considered the primary cause of this pain. Studies demonstrate that arthrosis of the posterior facet of the subtalar joint strongly correlates with lateral pain in adult-acquired flatfoot deformity. Both conditions are related to hindfoot valgus deformity. Although lateral column lengthening is a powerful tool for correction of flatfoot deformity, its effect on hindfoot deformity is less defined. Lateral column lengthening provides better correction of the longitudinal arch of the midfoot and realignment of the medial column than other osteotomies. A medializing calcaneal osteotomy has a significant linear effect on hindfoot valgus alignment. Spring ligament reconstruction and medial cuneiform opening-wedge osteotomies have less effect on hindfoot alignment than the medial calcaneal slide.
RECOMMENDED READINGS
Ellis SJ, Deyer T, Williams BR, Yu JC, Lehto S, Maderazo A, Pavlov H, Deland JT. Assessment of lateral hindfoot pain in acquired flatfoot deformity using weightbearing multiplanar imaging. Foot Ankle Int. 2010 May;31(5):361-71. doi: 10.3113/FAI.2010.0361. PubMed PMID:

Question 76

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

Explanation

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

Question 77

Figure 39 shows the radiograph of a 4-month old infant who has been undergoing weekly casting since birth for a congenital equinovarus deformity. Management should now consist of

Explanation

DISCUSSION: The radiograph shows the development of a rocker-bottom foot deformity. A rocker-bottom foot occurs in the treatment of clubfoot when casting is continued in the presence of a very tight gastrocnemius-soleus complex and an uncorrected hindfoot. While there are some preliminary reports on using Botox injection and continued casting for the equinus deformity, most authors recommend posterior or posterior medial release. Percutaneous tenotomy has been recently recommended with the resurgence of the Ponsetti technique.
REFERENCES: Lehman WB, Atar D: Complications in the management of talipes equinovarus, in Drennan JC (ed): The Child’s Foot and Ankle. New York, NY, Raven Press, 1992,

pp 135-136.
Herring JA: Tachdjian’s Pediatric Orthopedics, ed 4. Philadelphia, PA, WB Saunders, 2002,

pp 927-935.
Tachdjian MO: Pediatric Orthopedics, ed 2. Philadelphia, PA, WB Saunders, 1990,

pp 2461-2564.

Question 78

A 45-year-old man feels a pop in the anterior aspect of his elbow while lifting furniture. He denies any antecedent pain or injury. Which examination method is best for diagnosing a distal biceps rupture?

Explanation

EXPLANATION:

Question 79

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 80

-Figure 235 is the radiograph of a 75-year-old woman who is seen in the emergency department following a low-energy fall. What is the most appropriate treatment based on her radiographic findings?

Explanation

Question 81

A Trendelenburg gait is most likely to be seen in association with

Explanation

DISCUSSION: A Trendelenburg gait results from weakness of the gluteus medius, which is innervated by the L5 nerve root. A paracentral disk herniation at L4-L5 most commonly results in an L5 radiculopathy and thus weakness of the gluteus medius. A paracentral herniation at L5-S1 most commonly affects the S1 nerve root. A paracentral herniation at L3-L4, a central herniation at L3-L4, and a far lateral herniation at L4-L5 all affect the L4 root.
REFERENCES: Fardon DF, Garfin SR, Abitbol J, et al (eds): Orthopedic Knowledge Update: Spine 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 323-332.
Andersson GB, Deyo RA: History and physical examination in patients with herniated lumbar discs. Spine 1996;21:10S-18S.

Question 82

Which of the following tissues used for anterior cruciate ligament (ACL) reconstruction has the highest maximum load to failure?

Explanation

DISCUSSION: While the patellar tendon ligament is considered by many to be the tissue of choice for ACL reconstruction, more recent studies have shown that the quadruple semitendinosus and gracilis tendon graft has the greatest stiffness and offers the highest maximum load to failure.
REFERENCES: Hamner DL, Brown CH Jr, Steiner ME, Hecker AT, Hayes WC: Hamstring tendon grafts for reconstruction of the anterior cruciate ligament: Biomechanical evaluation of the use of multiple strands and tensioning techniques. J Bone Joint Surg Am 1999;81:549-557.
Cooper DE, Deng XH, Burstein AL, Warren RF: The strength of the central third patellar tendon graft: A biomechanical study. Am J Sports Med 1993;21:8l8-823.
Brown CH Jr, Steiner ME, Carson EW: The use of hamstring tendons for anterior cruciate ligament reconstruction: Technique and results. Clin Sports Med 1993;12:723-756.
Engebretsen L, Lewis JL: Graft selection and biomechanical considerations in ACL reconstruction. Sports Med Arthroscopy Rev 1996;4:336-341.

Question 83

Figure 26 shows the MRI scan of a 60-year-old man who has had groin pain for the past 2 months. The patient reports pain with ambulation, and examination reveals an antalgic gait. He denies any history of steroid or alcohol abuse. Plain radiographs are normal. Management should include

Explanation

DISCUSSION: The patient has transient osteoporosis of the hip. Transient osteoporosis is usually a self-limited condition that is most frequently seen in women in the third trimester of pregnancy and in men in the sixth decade of life. Transient osteoporosis is best treated with protected weight bearing.
REFERENCE: Guerra JJ, Steinberg ME: Distinguishing transient osteoporosis from avascular necrosis of the hip. J Bone Joint Surg Am 1995;77:616-624.

Question 84

Figures 169a through 169c show the radiograph and MRI scans of a 74-year-old woman who has had back and bilateral leg pain for the past 6 months. Nonsurgical management has failed to provide relief. What is the best option for surgical treatment? Review Topic

Explanation

The patient has symptoms of lumbar spinal stenosis and radiographic evidence of a grade I degenerative spondylolisthesis at L4-5. Surgical treatment has been shown to provide better clinical outcomes than nonsurgical management. Treatment for spondylolisthesis remains somewhat controversial but posterior lumbar instrumented arthrodesis is best supported in the literature. Decompression alone places the patient at risk for recurrent stenosis and progression of deformity. Noninstrumented arthrodesis for this condition results in high rates of nonunion and worsened longterm outcomes. There is insufficient evidence to support the role for interbody arthrodesis (either through an anterior or posterior approach) compared with posterior decompression and arthrodesis.

Question 85

Figures 21a and 21b show the radiographs of a 12-year-old patient with an L4-level myelomeningocele who has scoliosis that has been slowly progressing for the past several years. There has been no loss of motor function. An MRI scan shows no syringomyelia or increased hydrocephalus. Management should consist of

Explanation

DISCUSSION: Scoliosis is a common occurrence in children with myelomeningocele, with the incidence increasing as the neurologic level moves cephalad. The rate of pseudarthrosis for isolated anterior or posterior fusions has been reported as high as 75%. The combination of anterior and posterior fusions with some type of instrumentation has been shown to decrease the rate of pseudarthrosis to 20%. Brace treatment in smaller curves can be used as a temporizing measure to delay surgery, but as with idiopathic scoliosis, the brace is ineffective for larger curves. Observation is not indicated with a curve of this magnitude.
REFERENCES: Ward WT, Wenger DR, Roach JW: Surgical correction of myelomeningocele scoliosis: A critical appraisal of various spinal instrumentation systems. J Pediatr Orthop 1989;9:262-268.
Muller EB, Nordwall A: Brace treatment of scoliosis in children with myelomeningocele. Spine 1994;19:151-155.

Question 86

Which of the following findings is most prognostic for the ability of a young child with cerebral palsy to walk?

Explanation

DISCUSSION: Several studies have shown that sitting ability by age 2 years is highly prognostic of walking. Molnar and Gordon reported that children not sitting independently by age 2 years had a poor prognosis for walking. Wu and associates reported that children sitting without support by age 2 years had an odds ratio of 26:1 of walking compared with those unable to sit. This was far higher than the odds ratios for cerebral palsy location, motor dysfunction, crawling, creeping, scooting, or rolling.
REFERENCES: Molnar GE, Gordon SU: Cerebral palsy: Predictive value of selected clinical signs for early prognostication of motor function. Arch Phys Med Rehabil 1976;57:153-158.
Wu YW, Day SM, Strauss DJ, et al: Prognosis for ambulation in cerebral palsy: A population-based study. Pediatrics 2004;114:1264-1271.

Question 87

Figure 33 shows the AP and lateral radiographs of an obese 58-year-old man who underwent a cementless total hip arthroplasty 6 years ago. He reports no pain, and examination reveals a normal gait and painless hip range of motion. What is the most likely diagnosis?

Explanation

DISCUSSION: Osteolysis of an otherwise well-functioning total hip arthroplasty is a recognized complication, and its radiographic appearance is typical, as shown here. Distal osteolysis, such as that shown here, is more prevalent when there is noncircumferential sealing of the proximal femoral canal.
REFERENCES: Pellicci PM, Tria AJ Jr, Garvin KL (eds): Orthopaedic Knowledge Update: Hip and Knee Reconstruction 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000, pp 175-180.
Engh CA, Massin P, Suthers KF: Roentgenographic assessment of the biologic fixation of porous-surfaced femoral components. Clin Orthop 1990;257:107-128.

Question 88

The radiograph seen in Figure 67 reveals an ankle fracture in a 65-year-old woman who slipped on the ice. She has a history of diabetes mellitus for the past 7 years and reports that she maintains fair control of her diabetes; her last HgbA1c was 8%. The patient is a community ambulatory who lives independently. Examination reveals she has absent sensation with the 5.07 monofilament. When determining management, the physician must consider which of the following?

Explanation

Increased immobilization and delayed weight bearing are indicated in the neuropathic population after treating an ankle fracture. Patients with diabetes mellitus and peripheral neuropathy have higher complication rates following ankle fractures treated surgically or nonsurgically. The elevated HgbA1c and neuropathy both predict a higher complication rate with this fracture. Outcomes after nonsurgical management of this fracture are poorer than after surgical treatment. Early bone grafting is not recommended in closed fractures, but the use of supplemental internal fixation is recommended because of the high risk of nonunion. More substantial constructs with supplemental fixation, locking fixation, fixation through the calcaneus and talus into the tibia, or external fixation are necessary. Primary arthrodesis is not recommended in this fracture pattern or in a relatively active patient.

Question 89

Figure 40 shows the radiograph of a 30-year-old woman who has a painful elbow. Examination reveals a deformed skull, multiple cafe-au-lait spots, and bone deformities. What is the most likely diagnosis?

Explanation

DISCUSSION: Findings in patients with McCune-Albright syndrome include polyostotic fibrous dysplasia, multiple cafe-au-lait spots, and precocious puberty. The bone changes in NF-1 resemble nonossifying fibromas, not fibrous dysplasia. NF-2 has little bony change with typical ocular abnormalities. Paget’s disease occurs in older individuals and does not present with cafe-au-lait spots. Ollier’s disease (multiple enchondromatosis) may show bone changes but not the other findings.
REFERENCES: Albright F, Butler AM, Hampton AO, et al: Syndrome characterized by osteitis fibrosa disseminata, areas of pigmentation and endocrine dysfunction with precocious puberty in females. N Engl J Med 1937;216:727-746.
Danon M, Robboy SJ, Kim S, Scully R, Crawford JD: Cushing syndrome, sexual precocity, and polyostotic fibrous dysplasia (Albright syndrome) in infancy. J Pediatr 1975;87:917-921.
Grabias SL, Campbell CJ: Fibrous dysplasia. Orthop Clin North Am 1977;8:771-783.

Question 90

What is the most common malignant bone tumor seen in patients with multiple hereditary exostosis?

Explanation

DISCUSSION: Secondary chondrosarcomas are most common in patients with multiple hereditary exostosis. Dedifferentiated chondrosarcoma is less common and refers to bone lesions in which a high-grade spindle cell sarcoma component is located immediately adjacent to a low-grade cartilage neoplasm. Mesenchymal chondrosarcoma, clear cell chondrosarcoma, and periosteal osteosarcoma are no more common in patients with multiple hereditary exostosis than in the general population.
REFERENCES: Mirra JM: Bone Tumors: Clinical, Radiologic, and Pathologic Correlations. Philadelphia, PA, Lea and Febiger, 1989, pp 1660-1669.
Simon MA, Springfield DS, et al: Common Malignant Bone Tumors: Chondrosarcoma. Surgery for Bone and Soft Tissue Tumors. Philadelphia, PA, Lippincott Raven, 1998, pp 275-286.

Question 91

An 11-year-old girl is struck in the leg by a loaded sled while sledding and is seen in the emergency department; she is reporting severe knee pain. Radiographs are read as normal. Examination reveals that she is exquisitely tender over the proximal tibial physis. The neurovascular examination is normal. What is the next step in management? Review Topic

Explanation

The anatomic lesion in this patient is not exactly defined, but she has most likely sustained an injury about the knee. A Salter-Harris type I proximal tibial physeal fracture is likely. The normal radiograph reading can be misleading because these injuries may displace and spontaneously reduce. The child is at risk of compartment syndrome although she is currently not displaying signs of it. Thus, even though this injury may seem trivial by radiographic findings, it should be treated like a knee dislocation with a risk of late developing compartment syndrome. MRI or CT may be necessary to define the injury. She does not require emergent treatment, but merits close observation for possible compartment syndrome. Any of the possible injuries about the knee can be unstable and require internal fixation after reduction.

Question 92

An 18-year-old man sustained closed humeral shaft and forearm fractures of his dominant arm in a motor vehicle accident. Neurovascular examination is intact, and his condition is stable. The best course of action for management of the injuries should be

Explanation

DISCUSSION: Fractures above and below the elbow constitute floating elbow injuries and are best treated with internal fixation to allow early range of motion and to prevent elbow stiffness. Use of a long arm cast would promote elbow stiffness. External fixation is indicated primarily for open injuries.
REFERENCES: Beaty JH (ed): Orthopaedic Knowledge Update 6. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1999, pp 271-286.
Bell MJ, Beachamp CG, Kellam JK, McMurtry RY: The results of plating humeral shaft fractures in patients with multiple injuries: The Sunnybrook experience. J Bone Joint Surg Br 1985;67:293-296.

Question 93

A 14-year-old boy has an asymptomatic mass on the right arm. MRI scans and biopsy specimens are shown in Figures 51a through 51d. Immunostaining is positive for desmin. Additional staging studies should include

Explanation

DISCUSSION: The patient has rhabdomyosarcoma. Axilliary node and bone marrow biopsy are part of the staging because about 12% of patients with rhabdomyosarcoma of the extremity have evidence of lymph nodes metastases at presentation. Bone marrow metastases have been shown to portend a worse prognosis.
REFERENCES: Lawrence W, Jr., Hays DM, Heyn R, Tefft M, Crist W, Beltangady M, et al: Lymphatic metastases with childhood rhabdomyosarcoma: A report from the Intergroup Rhabdomyosarcoma Study. Cancer 1987;60:910-915.
Schleiermacher G, Peter M, Oberlin O, et al: Increased risk of systemic relapses associated with bone marrow micrometastasis and circulating tumor cells in localized ewing tumor. J Clin Oncol 2003;21:85-91.

Question 94

A 70-year-old man reports symptomatic medial knee pain that has become progressively worse during the past year. MRI reveals a complex, posterior horn medial meniscus tear with associated medial lateral and patellofemoral cartilage defects. Radiographs reveal medial joint space narrowing and osteophytes in the other compartments. What treatment is most likely to provide long-term, durable relief of symptoms?

Explanation

DISCUSSION:
Total knee replacement is a well-established surgery for diffuse, symptomatic osteoarthritis of the knee joint, and its efficacy has been shown in many studies. According to the 2008 AAOS Clinical Practice Guideline, Treatment of Osteoarthritis of the Knee, arthroscopy in the setting of existing osteoarthritis is efficacious for relieving the signs and symptoms of a torn meniscus but not for osteoarthritis. Likewise, in young and active patients, clinical outcomes show improvement after realignment osteotomy for single-compartment osteoarthritis. Unicondylar knee replacement is not indicated for tricompartmental disease of the knee.

Question 95

Which of the following factors has been shown to increase mortality in poly-trauma patients with severe head injuries?

Explanation

DISCUSSION: The factor most likely to adversely affect long term outcome in poly-trauma patients with severe brain injury is intraoperative hypotension.
Chesnut et al demonstrated that hypotension (SBP <90mmHg) was profoundly detrimental, occurring in 35% of these patients and associated with 150% increase in mortality.
Pietropaoli et al reviewed 53 patients with severe head injuries and required early surgical intervention (surgery within 72 hours of injury). All patients were initially normotensive on arrival. There were 17 patients (32%) who developed intra-operative hypotension and 36 (68%) who remained normotensive throughout surgery. The mortality rate was 82% in the IH group and 25% in the normotensive group.

Question 96

A 74-year-old patient is seen for follow-up 6 weeks after undergoing a total shoulder arthroplasty for glenohumeral osteoarthritis. The patient missed the 2-week follow-up appointment and is currently wearing a sling. The incision is well healed with no signs of breakdown. Examination reveals that passive range of motion is forward elevation of 90 degrees, external rotation at the side 0 degrees, and internal rotation up the back is to the level of the greater trochanter. A radiograph shows no signs of fracture or dislocation. What is the next most appropriate management for this patient? Review Topic

Explanation

The patient has a postoperative stiff shoulder. The patient missed follow-up appointments and has not been participating in physical therapy for stretching. Based on normal radiographic findings, the shoulder is not dislocated; therefore, physical therapy should begin immediately. Continued sling immobilization will further worsen the stiffness. There is no indication of an infection or rotator cuff tear. Deep venous thrombosis would present with abnormal swelling and pain.

Question 97

A 50-year-old alcoholic man has erythema and swelling in his entire dominant upper extremity. He has a WBC of 15,000/mm3, a temp of 101 oF (38.3 oC), and a blood pressure of 90/60 mm Hg. After hemodynamic stabilization, the cellulitic forearm is longitudinally incised dorsally and volarly. The forearm muscles are normal in appearance; however, the subcutaneous fat is necrotic. A culture will most likely reveal

Explanation

Necrotizing fasciitis is frequently caused by strep infections. Cellulitis, which is an inflammatory infection of the subcutaneous tissues, is usually due to Staph or Strep infections (Haemophilus is also seen in children). Significant Streptococcal infections include erysipelas, which produces a progressively enlarging red, raised painful plaque, severe toxicity, fever, leukocytosis and bacteremia; Necrotizing fasciitis produces XXXXX. Clostridium perforingens typically causes gas gangrene (which can also develop from gram neg. and strep infections), presenting as progressive pain, distal edema, and a malodorous serosanguinous discharge.

Question 98

A 36-year-old man has a 2-day history of acute lower back pain with severe radicular symptoms in the left lower extremity. The patient has a positive straight leg test at 40 degrees on the left side and mild decreased sensation on the dorsum of the left foot. What is the most appropriate management at this time? Review Topic

Explanation

In the absence of any severe progressive neurologic deficits or other red flags, the most appropriate management for an acute lumbar disk herniation is nonsurgical care. Conservative treatments such as limited bed rest, anti-inflammatory medications, and judicious use of pain medications are appropriate in this clinical situation. Up to 90% of patients will experience a resolution of symptoms without the need for surgical intervention within a 3-month window. In the acute setting, with no neurologic deficits, immediate MRI of the lumbar spine is neither beneficial nor warranted. Likewise, without signs of an acute deficit, emergent surgical intervention and caudal epidural steroid injections are not needed.

Question 99

03 Which of the following findings is the best indication for the use of temporary external fixation of a femoral shaft fracture?

Explanation

Tulane defines “Orthopaedic Tunnel Vision” as a condition commonly associated with a young MD at the Bulldog without a proper wing-man, trying to make advances on the wrong patron due to his relatively easy 80-hour work week schedule and a few too many refined hops.

Skeletal Trauma (p. 1967) describes “Orthopaedic Tunnel Vision” as looking at the orthopaedic injury without considering the patient’s injury in general. Femoral shaft fractures are typically high energy injuries which often do not occur in isolation. In these fractures, it is particularly important to not have tunnel vision.

Indications for temporary bridging external fixation includes hemodynamic instability
(ans. 2), acidosis, hypothermjia, hypoxemia, coagulopathy, sepsis or severely contaminated soft tissues that cannot be adequately debrided. Definitive fixation is performed after the general surgical and medical issues have resolved.

The other answer choices, including the type IIIA open fracture are not contraindications to definitive fixation in themselves (typically IM nailing—antegrade or retrograde).

Question 100

A 15-year-old dancer who has had brief episodes of back pain over the past 2 years now reports a 3 month history of low back pain and a decreased tolerance for dance. Figure 22a-c show flexion and extension x-rays and CT scan. She reports no leg pain, nor any bowel or bladder difficulties. Management should now consist of

Explanation

rays show a Grade I spondylolisthesis. Studies have shown that pts with grade 3 or 4 spondylolisthesis had a minimal success (8%) with nonoperative treatment, whereas pts with grade 1 or 2 spondylolisthesis had significant relief of pain. Conservative tx included rest, NSAIDs, abdominal strengthening exercises, hamstring stretching exercises, or traction.

Full Question & Answer Text (for Search Engines)

Question 1:

Following a fall from a height of 5 feet, a patient reports pain along the lateral border of the foot. The CT scan shown in Figure 54 indicates what pathology?

Options:

Impaction injury of the cuboid
Retracted os peroneum
Fifth metatarsal avulsion fracture
Avulsion injury of the bifurcate (Y) ligament
Lisfranc injury

Correct Answer: Avulsion injury of the bifurcate (Y) ligament

Explanation:

DISCUSSION: The CT scan reveals an avulsion of the dorsal beak of the anterior process of the calcaneus. This common fracture is an avulsion of the origin of the bifurcate ligament, which runs from the anterior calcaneal process to both the cuboid and the lateral aspect of the navicular. An inversion mechanism is common, and the fracture is often missed in evaluation for a suspected ankle sprain. MRI may be useful in the diagnosis of these occult injuries, and suspicion should be present when tenderness exists over the superior portion of the anterior process of the calcaneus.
REFERENCE: Robbins MI, Wilson MG, Sella EJ: MR imaging of anterosuperior calcaneal process fractures. Am J Roentgenol 1999;172:475-479.

Question 2:

Options:

Autogenous iliac crest bone graft
Calcium phosphate
Calcium sulfate
Tricalcium phosphate
Coralline hydroxyapatite blocks

Correct Answer: Calcium phosphate

Explanation:

Question 3:

Options:

Vitamin A deficiency
Low serum testosterone
Low serum thyroxine
Vitamin D deficiency
Hypocalcemia

Correct Answer: Vitamin A deficiency

Explanation:

Question 4:

In a retroperitoneal approach to the lumbar spine, what nerve is commonly found on the psoas muscle?

Options:

Ilioinguinal
Iliohypogastric
Genitofemoral
Obturator
Femoral

Correct Answer: Genitofemoral

Explanation:

Question 5:

When making a comparison to autograft incorporation, the inflammatory process in allograft tissue anterior cruciate ligament (ACL) reconstruction

Options:

occurs earlier.
occurs later.
is prolonged.
is shortened.

Correct Answer: is prolonged.

Explanation:

Question 6:

Options:

Normal shoulder strength and function
Local sensory deficits
Fracture union
Infection
Malunion

Correct Answer: Malunion

Explanation:

Question 7:

Options:

higher incidence of patellar clunk and similar implant survivorship.
higher incidence of patellar clunk and superior implant survivorship.
lower incidence of patellar clunk and superior implant survivorship.
lower incidence of patellar clunk and similar implant survivorship. The images show a left posterior stabilized knee prosthesis and a right cruciate sacrificing (ultracongruent / dished type) knee prosthesis. Posterior stabilized designs have a risk of patellar clunk due to the presence of the femoral box with some designs, such as the one shown, exhibiting higher rates. Clinical outcomes are similar between cruciate-retaining, cruciate- sacrificing and posterior stabilized designs.

Correct Answer: higher incidence of patellar clunk and similar implant survivorship.

Explanation:

Question 8:

Options:

Excessive varus laxity at 30 degrees of flexion
Reverse pivot shift
Posterolateral drawer laxity at 90 degrees of flexion
Asymmetric tibial external rotation at 30 degrees of flexion
Positive external rotation/recurvatum test

Correct Answer: Asymmetric tibial external rotation at 30 degrees of flexion

Explanation:

Question 9:

Options:

Oncogenic rickets
Calcium sequestration by the tumor
Elevated alkaline phosphatase level
Tumor cachexia
L5 neuropathy

Correct Answer: Oncogenic rickets

Explanation:

Question 10:

Options:

Medial collateral ligament repair
Medial collateral ligament reconstruction
Hinged external fixation
Lateral collateral ligament repair
Lateral collateral ligament reconstruction

Correct Answer: Lateral collateral ligament reconstruction

Explanation:

Question 11:

Varus malalignment after a talar neck fracture with medial comminution causes a decrease in what motion?

Options:

Tibiotalar dorsiflexion
Tibiotalar plantarflexion
Subtalar eversion
Subtalar inversion
Internal rotation

Correct Answer: Tibiotalar dorsiflexion

Explanation:

Question 12:

Scapular notching following reverse shoulder arthroplasty may be minimized by what technical modification? Review Topic

Options:

Horizontal humeral cut
Superior inclination of the baseplate
Inferior inclination of the baseplate
Use of a 36-mm glenosphere
Use of a retentive polyethylene liner

Correct Answer: Inferior inclination of the baseplate

Explanation:

Question 13:

Options:

Proceed with the revision as planned
Obtain cultures and proceed with revision of the acetabulum only
Obtain cultures and proceed with revision of the femur only
Obtain cultures, remove the implants, and insert an antibiotic spacer
Obtain cultures and close

Correct Answer: Proceed with the revision as planned

Explanation:

DISCUSSION: Despite the negative aspiration preoperatively, intraoperative findings are suspicious for infection. Additionally, the preoperative blood work is also concerning for infection with an elevated CRP and ESR. The frozen section is also positive. Most important is the unreliability of the Gram stain. Numerous investigators have show high false negative rates for Gram stain in chronic periprosthetic infection. The Gram stain should not be relied on for decision-making in revision surgery, particularly when other investigations point to infection. With the information available, the diagnosis is deep infection. The best course of action is to obtain cultures, remove the implants, and insert an antibiotic spacer. Only obtaining cultures and closing would require a second operation to remove the implants if the cultures are positive.
REFERENCES: Sanzen L, Sundberg M: Periprosthetic low-grade hip infections: Erythrocyte sedimentation rate and C-reactive protein in 23 cases. Acta Orthop Scand 1997;68:461-465.
Spangehl MJ, Hanssen AD, Osman DR: Diagnosis and treatment of the infected hip arthroplasty, in Morrey BF(ed
A
)
L
:
-M
Jo
a
i
d
n
e
t
na
R
C
e
o
p
p
l
y
acement Arthroplasty, ed 3. Philadelphia, PA, Churchill Livingstone, 2003, pp 856-874. Question 71
A 79-year-old patient has a history of peripheral vascular disease and reports chronic knee pain. She has had coronary artery disease treated with angiography and stents on two occasions. Peripheral pulses are absent in both lower extremities, but the patient is disabled by advanced chronic degenerative arthritis in her right knee and would like to proceed with a total knee arthroplasty. The next most appropriate evaluation should include which of the following?
Ankle-brachial index of the affected lower extremity
Femoral popliteal angiography
Venous Dopplers of both lower extremities
MRI of the popliteal fossa
Radiographs to identify calcified plaques in the femoral artery
DISCUSSION: This question is designed to draw attention to the fact that peripheral vascular disease carries an increased risk of complications for the patient and should be carefully evaluated. The vascular surgeon will make the choice of revascularization or surgical clearance for knee reconstruction based on the initial results of the ankle-brachial index.
REFERENCE: Smith DE, McGraw RW, Taylor DC, et al: Arterial complications and total knee arthroplasty. J Am Acad Orthop Surg 2001 ;9:253-257.

Question 14:

Options:

Chondrosarcoma
Chordoma
Metastatic renal cell carcinoma
Metastatic breast cancer
Infection

Correct Answer: Chordoma

Explanation:

Question 15:

Options:

ixation of the coronoid fragment
Radial head arthroplasty
Repair or reconstruction of the lateral collateral ligament (LCL) complex
Repair or reconstruction of the medial collateral ligament (MCL) This represents a terrible triad injury, with elbow dislocation, radial head fracture, and coronoid fracture. The LCL complex is typically disrupted in this injury pattern. Repair or reconstruction of this structure provides the greatest increase in rotational stability of the elbow.

Correct Answer: Repair or reconstruction of the lateral collateral ligament (LCL) complex

Explanation:

Question 16:

What normal tissue has a low signal intensity (appears black) on both T1- and T2-weighted images?

Options:

Tendon
Fat
Joint fluid
Intervertebral disk
Bone marrow

Correct Answer: Tendon

Explanation:

Question 17:

A 24-year-old man sustained a bilateral C5-6 facet dislocation in a car accident and was intubated at the scene. He remains sedated in the intensive care unit

Options:

mm rostral caudal cord edema
Disruption of the anterior longitudinal ligament
Edema in the soft tissue anterior to the spine
Diffuse cord edema
mm cord hematoma

Correct Answer: mm cord hematoma

Explanation:

Question 18:

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 19:

According to Musculoskeletal Infection Society (MSIS) guidelines, which set of patient laboratory study results fits the definition of chronic prosthetic joint infection?

Options:

ESR 25 mm/hr, CRP 7 mg/L, joint aspiration WBC count 252, 82% neutrophils, and negative leukocyte esterase
Erythrocyte sedimentation rate (ESR) 50 mm/hr, C-reactive protein (CRP) 8 mg/L, joint aspiration white blood cell (WBC) count 542, 62% neutrophils, and positive leukocyte esterase
ESR 42 mm/hr, CRP 12 mg/L, joint aspiration WBC count 3,540, 72% neutrophils, and positive leukocyte esterase
ESR 20 mm/hr, CRP 15 mg/L, joint aspiration WBC count 4,135, 54% neutrophils, and negative leukocyte esterase

Correct Answer: Erythrocyte sedimentation rate (ESR) 50 mm/hr, C-reactive protein (CRP) 8 mg/L, joint aspiration white blood cell (WBC) count 542, 62% neutrophils, and positive leukocyte esterase

Explanation:

Question 20:

An 80-year-old woman notes a painless mass posterior to her left knee. MRI scans are shown in Figures 31a and 31b. What is the best course of action?

Options:

Observation
Medical management
Needle biopsy
Incisional biopsy
Resection

Correct Answer: Observation

Explanation:

DISCUSSION: The MRI scans show a popliteal cyst (Baker’s cyst) in its most common location. The cyst emerges from the knee joint between the medial head of the gastrocnemius muscle and the tendon of the semimembranosus muscle. These images are diagnostic; therefore, no further work-up is indicated. Since the patient is asymptomatic, no treatment is necessary.
REFERENCES: Dlabach JA: Nontraumatic soft tissue disorders, in Canale ST (ed): Campbell’s Operative Orthopaedics, ed 10. Philidelphia, PA, Mosby, 2003, vol 1, pp 885-969.
Fritschy D, Fasel J, Imbert JC, et al: The popliteal cyst. Knee Surg Sports Traumatol Arthrosc 2006;14:623-628.

Question 21:

Which of the following pieces of equipment currently offers the greatest opportunity for lowering the number of equestrian injuries?

Options:

Knee pads
Wrist guards
Boots
Helmets
Quick release stirrups

Correct Answer: Boots

Explanation:

Question 22:

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 23:

Options:

Grade III chondrosis of the proximal patella
Caton-Deschamps ratio of 1:1
Tibial tubercle-trochlear groove (TT-TG) distance of 21 mm
Q angle of 17 degrees

Correct Answer: Grade III chondrosis of the proximal patella

Explanation:

DISCUSSION
TTO is a common treatment for patellofemoral instability. The angle of correction must be customized to each patient’s anatomy. For this patient, the orthopaedic surgeon plans an osteotomy that will both anteriorize and medialize the tubercle. This will consistently result in
a change of patellofemoral kinematics and contact pressures. Medialization decreases lateral and increases medial patellofemoral contact pressures, and anteriorization shifts contact pressures from distal to proximal. Significant anteriorization may not be desired in a patient with proximal patellar chondrosis unless a concomitant chondral procedure is performed as well. The patellar height (Caton-Deschamps ratio) is normal, precluding the need for distalization but not medialization. The TT-TG distance, at more than 20 mm, is a strong indication for osteotomy. The Q angle, although a less precise indicator of malalignment, is also elevated and would be considered an indication for osteotomy.
CLINICAL SITUATION FOR QUESTIONS 37 THROUGH 41
A healthy, active 18-year-old man has acute-onset right knee pain and an inability to fully extend his knee following an attempt to stand from a seated position yesterday. He sustained a noncontact injury to his right knee while playing basketball 2 years ago and underwent primary anterior cruciate ligament (ACL) reconstruction with bone-patella-tendon-bone autograft and medial meniscus repair. He sustained another noncontact injury to the same knee 8 months later and underwent a revision ACL reconstruction using soft-tissue allograft and revision medial meniscus repair. He reports multiple episodes of “giving way” of his knee, but no pain prior to yesterday’s acute injury.

Question 24:

Options:

Anterior tibial artery
Posterior tibial artery
Superficial peroneal nerve
Saphenous nerve

Correct Answer: Posterior tibial artery

Explanation:

Question 25:

Options:

MRI of the foot
Static ultrasound examination of the foot in dorsiflexion
Lateral radiograph of the foot in maximum plantar flexion
Lateral radiograph of the foot in maximum dorsiflexion
CT of the foot

Correct Answer: Lateral radiograph of the foot in maximum plantar flexion

Explanation:

DISCUSSION: The clinical photograph shows a rocker-bottom deformity, and the lateral radiograph suggests a congenital vertical talus deformity. A lateral radiograph of the foot in maximum plantar flexion is needed to demonstrate the fixed position of the deformity with malalignment of the talar-metatarsal axis. A fixed dislocation of the navicular on the talus differentiates a congenital vertical talus from the oblique talus with talonavicular subluxation.
REFERENCES: Kumar SJ, Cowell HR, Ramsey PL: Vertical and oblique talus. Instr Course Lect 1982;31:235-251.
Kodros SA, Dias LS: Single-stage correction of congenital vertical talus. J Pediatr Orthop 1999;19:42-48.
Herring JA: Disorders of the foot, vertical talus, in Herring JA (ed): Tachdjian’s Pediatric Orthopaedics, from the Texas Scottish Rite Hospital for Children, ed 3. Philadelphia, PA,
WB Saunders, 2002, pp 959-967.

Question 26:

Which radiographic abnormality most accurately serves as a predictor of ankle syndesmosis disruption?

Options:

Medial clear space equal to the superior clear space on the anteroposterior (AP) view
Tibiofibular overlap exceeding 6 mm on the AP view
Tibiofibular clear space exceeding 6 mm on AP view
Talocrural angle symmetric to the opposite side

Correct Answer: Tibiofibular clear space exceeding 6 mm on AP view

Explanation:

DISCUSSION
Normal syndesmotic relationships include a tibiofibular clear space smaller than 6 mm on both AP and mortise views. In a 1989 cadaveric study by Harper and Keller, a tibiofibular clear space exceeding 6 mm on both the AP and mortise views was the most reliable predictor of early syndesmotic widening. Tibiofibular overlap is measured 1 cm proximal to the plafond. Normal values exceed 6 mm or 42% of the width of the fibula on the AP view, or 1 mm on the mortise view. Proximal fibula fracture can occur in isolation without syndesmotic injury, frequently after direct trauma. The medial clear space is the distance between the lateral border of the medial malleolus and the medial border of the talus and is measured at the level of the talar dome. In the mortise view with the ankle in neutral dorsiflexion, the medial clear space should be equal to or smaller than the superior clear space between the talar dome and the tibial plafond. ?A normal medial clear space may be present with syndesmotic injury and consequently lacks sensitivity and specificity.
RECOMMENDED READINGS
Zalavras C, Thordarson D. Ankle syndesmotic injury. J Am Acad Orthop Surg. 2007 Jun;15(6):330-9. Review. PubMed PMID: 17548882.
View Abstract at PubMed
Wuest TK. Injuries to the Distal Lower Extremity Syndesmosis. J Am Acad Orthop Surg. 1997 May;5(3):172-181. PubMed PMID: 10797219.
View Abstract at PubMed
Harper MC, Keller TS. A radiographic evaluation of the tibiofibular syndesmosis. Foot Ankle. 1989 Dec;10(3):156-60. PubMed PMID: 2613128.
View Abstract at PubMed
CLINICAL SITUATION FOR QUESTIONS 37 THROUGH 40
A 41-year-old man sustained a twisting injury while running up stairs 4 weeks ago. He was treated in an ankle brace and has been bearing weight since the injury occurred. He has no history of ankle problems, but he now has ankle pain, swelling, and instability. The pain is aggravated by stairs, and the instability is worse on unlevel ground. Radiographs do not show a fracture.

Question 27:

A 56-year-old man sustained a nondisplaced extra-articular fracture of the proximal aspect of the third metatarsal after dropping a heavy object on his left foot. Management should consist of

Options:

open reduction and internal fixation.
external bone stimulation.
percutaneous pin fixation.
weight bearing in a walking boot or walking cast.
open reduction and internal fixation and primary tarsometatarsal joint fusion.

Correct Answer: weight bearing in a walking boot or walking cast.

Explanation:

Question 28:

The presence of S100B tumor marker typically corresponds with which of the following as being the most likely source of the metastasis?

Options:

Thyroid adenocarcinoma
Breast carcinoma
Gastrointestinal carcinoma
Melanoma
Astrocytoma

Correct Answer: Melanoma

Explanation:

DISCUSSION: Advances in development of new tumor markers and techniques of antigen retrieval have enhanced the sensitivity and reliability of identifying the primary source of metastasis. New markers such as CK7, CK20, CA125, and thyroid transcription factor-1
(TTF-1) can help to determine the origin of an adenocarcinoma or aid in the recognition of other tumors. In patients who do not have an obvious primary site of disease or screening radiographs, these new markers can help focus the search for and guide the treatment of the underlying lesion. CA125 is positive in patients with ovarian cancer, CK7 is positive in patients with breast and lung carcinoma, and CK20 is indicative of colon carcinoma if the CK7 marker is negative. Gastrointestinal stromal tumor (GIST) is positive for CD117 (c-kit) and CD34, whereas 75% of bronchogenic carcinomas are positive for TTF-1. Histochemical staining of the S100 protein family has been used for many years in the diagnosis of malignant melanoma. Recent markers HMB-45, MART-1, and Melan-A have proved to be useful in diagnosis of melanoma. S100B protein has been implicated in downregulation of p53 (oncosuppressor gene).
REFERENCES: Harpio R, Einarsson R: S100 proteins as cancer biomarkers with focus on S100B in malignant melanoma. Clin Biochem 2004;37:512-518.
Roodman GD: Mechanisms of bone metastasis. N Engl J Med 2004;350:1655-1664.

Question 29:

Options:

Skeletal traction and observation until the patient is better resuscitated
External fixation of both femurs
Plate and screw fixation of both femurs
Unreamed antegrade nailing of both femurs
Reamed retrograde nailing of both femurs Corrent answer: 5 Figures A-D are radiographs demonstrating bilateral femur fractures in an adequately resuscitated patient. This injury pattern is best treated with bilateral, reamed, retrograde femoral nails. This patient has been adequately resuscitated and should undergo definitive stabilization of his injuries. Indicators for adequate resuscitation are mean arterial pressure > 60, heart rate <100, urine output of 30 cc/hour, serum lactate of < 2.5, gastric mucosal pH > 7.3, and a base deficit of -2 to +2. Bilateral femoral shaft fractures are a relative indication for retrograde femoral nailing. When compared to antegrade nailing of this injury pattern, retrograde nailing has a decreased operative time because the extremities may be prepped and draped together, eliminating the need to re-position and re-prep the patient. Nork et al. performed a review of patients treated with reamed intramedullary nailing of a femoral shaft fracture. They found 54 patients with bilateral femoral shaft fractures. They report that mortality in these patients was 5.6% compared to 1.5% in the unilateral group. Bilateral fractures are also associated with a longer length of stay in the hospital and a longer length of stay in the intensive care unit. They conclude that patients with bilateral fractures sustain a higher injury burden than patients with unilateral injuries. Pape et al. performed a study to determine whether the use of a reamer that provides simultaneous irrigation and aspiration of intramedullary contents can lower the risk of pulmonary embolization when performing a femoral nail. The experiment was performed in sheep treated with femoral nails separated into 3 groups: reamed femoral nailing, reaming with irrigation and aspiration, and unreamed nailing. They conclude that in the presence of unilateral pulmonary injury, the effects of reaming may be minimized by irrigating and aspirating the canal. Brumback et al. wrote a review on intramedullary nailing of the femur comparing reamed and unreamed techniques. They report that reamed intramedullary nailing has not been associated increases in pulmonary complications while unreamed nailing has been shown to have slightly higher rates of delayed union and nonunion. They conclude that reamed interlocking intramedullary fixation remains the treatment of choice for femoral shaft fractures in adults. Figures A-D are radiographs demonstrating a femoral shaft fracture. Incorrect Answers:

Correct Answer: Unreamed antegrade nailing of both femurs

Explanation:

may be performed.
OrthoCash 2020

Question 30:

Figure 43 shows the lateral radiograph of a 12-year-old boy with mild osteogenesis imperfecta who injured his left elbow after pushing his brother. Treatment should consist of

Options:

closed reduction and cast immobilization.
closed reduction and percutaneous pinning.
open reduction and fixation using an absorbable suture.
open reduction and fixation using two Kirschner wires and a figure-of-8 tension band of absorbable suture.
open reduction and fixation using an intramedullary screw.

Correct Answer: open reduction and fixation using two Kirschner wires and a figure-of-8 tension band of absorbable suture.

Explanation:

Question 31:

What type of physical therapy is most effective for chronic noninsertional Achilles tendinopathy?

Options:

Stair climbing
Eccentric strengthening
Concentric strengthening
Isometric strengthening
Rope jumping

Correct Answer: Eccentric strengthening

Explanation:

DISCUSSION: Eccentric gastrocsoleus strengthening (especially with heavy loads) consistently has been shown to be superior in the management of Achilles tendinopathy. Decreases in pain and increases in strength have been demonstrated despite the frequently refractory nature of this condition.
REFERENCES: Richardson EG (ed): Orthopaedic Knowledge Update: Foot and Ankle 3. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2003, pp 91-102.
Vora AM, Myerson MS, Oliva F, et al: Tendinopathy of the main body of the Achilles tendon.
Foot Ankle Clin 2005;10:293-308.

Question 32:

Options:

Obtaining formal functional capacity testing
Waiting for final prosthesis fitting prior to full release
Minimize use of her prosthetic while at work
Allowing return to work when full elbow range of motion is seen
Offer outpatient psychological counseling

Correct Answer: Obtaining formal functional capacity testing

Explanation:

Question 33:

Options:

Ewing’s sarcoma
Osteosarcoma
Rhabdomyosarcoma
Osteomyelitis
Malignant fibrous histiocytoma

Correct Answer: Osteosarcoma

Explanation:

DISCUSSION: The radiographs show a bone-producing lesion in the distal femoral metaphysis in this case of classic osteosarcoma presenting in the most common location, the distal femur. The coronal MRI scan reveals a marrow-occupying lesion with extension into the soft tissues. The histology shows osteoid production by pleomorphic cells consistent with an osteosarcoma. Ewing’s sarcoma is a bone tumor characterized by uniform small blue cells on histology. Rhabdomyosarcoma is the most common childhood soft-tissue sarcoma. Osteomyelitis has an inflammatory appearance on histology. Malignant fibrous histiocytoma of bone has a lytic radiographic appearance and a pleomorphic storiform pattern without osteoid on histology.
REFERENCES: Wold LE, Adler CP, Sim FH, et al: Atlas of Orthopedic Pathology, ed 2. Philadelphia, PA, WB Saunders, 2003, p 179.
McCarthy EF, Frassica FJ: Pathology of Bone and Joint Disorders with Clinical and Radiographic Correlation. Philadelphia, PA, WB Saunders, 1998, p 205.

Question 34:

Options:

MRI
Surgical intervention
Activity modification
Cast immobilization

Correct Answer: Activity modification

Explanation:

Question 35:

Options:

Short radiolunate
Dorsal scapholunate interosseous
Volar lunotriquetral interosseous
Radioscaphocapitate

Correct Answer: Volar lunotriquetral interosseous

Explanation:

Question 36:

Options:

distal Chevron osteotomy.
proximal metatarsal osteotomy with soft-tissue release.
shoe wear modifications.
dorsal cheilectomy with Moberg osteotomy.
hallux metatarsophalangeal joint arthroplasty.

Correct Answer: shoe wear modifications.

Explanation:

Question 37:

After full healing from this injury, which option most likely will help to optimize this patient's activities?

Options:

Extra-depth shoes
Rocker-bottom soles
Figure-of-8 soft-ankle brace
A patellar-tendon-bearing brace

Correct Answer: Rocker-bottom soles

Explanation:

DISCUSSION
Midfoot fracture dislocations typically occur after a fall from a height or a motor vehicle collision involving severe dorsiflexion loading of the foot from a brake pedal or the floorboards. The deformity that results may be subtle because the subluxation may be a valgus or varus rotation around the midfoot rather than pure dorsiflexion. Early recognition and reduction is indicated to minimize secondary complications such as nerve injury or vascular compromise. Closed reduction usually necessitates formal anesthesia in an operating room to permit adequate relaxation and reduction. In many cases, satisfactory reduction can be accomplished closed, but the surgeon must be prepared to perform an open reduction if needed. The most common reason for failed closed reduction is that the talar head is caught by the tibialis posterior tendon (under which the talar head has protruded). This acts as a Chinese finger trap, preventing relocation by the usual distraction followed by
a plantar flexion maneuver. In these cases, open reduction is performed through a dorsomedial incision through which the tibialis posterior is retracted medially, allowing reduction of the talonavicular joint. The joints usually require pinning to maintain stability during healing. The long-term prognosis for these injuries is guarded because many patients develop degenerative changes in the Chopart joint. If symptomatic arthritis develops, helpful external supports are designed to limit sagittal motion at the joint (for example, carbon fiber inserts or rocker-bottom soles).
RECOMMENDED READINGS
Swords MP, Schramski M, Switzer K, Nemec S. Chopart fractures and dislocations. Foot Ankle Clin. 2008 Dec;13(4):679-93, viii. Doi: 10.1016/j.fcl.2008.08.004. Review. PubMed PMID: 19013402.
View Abstract at PubMed
Richter M, Thermann H, Huefner T, Schmidt U, Goesling T, Krettek C. Chopart joint fracture-dislocation: initial open reduction provides better outcome than closed reduction. Foot Ankle Int. 2004 May;25(5):340-8. PubMed PMID: 15134617.
View Abstract at PubMed

Question 38:

Figures 1 and 2 depict the postoperative radiographs obtained from a 22-year-old man who was involved in a motor vehicle accident. The most likely limitation in motion arising from this treatment is

Options:

loss of wrist flexion.
loss of wrist extension.
loss of elbow extension.
loss of pronation.

Correct Answer: loss of pronation.

Explanation:

EXPLANATION:
This patient sustained fractures of his radius and ulna; both were treated with plate and screw fixation. The plate used on the radius was straight, resulting in loss of the radial bow, which is critical for enabling the radius to curve around the ulna during pronation. This patient is unable to pronate beyond 20°. Schemitsch and Richards correlated a good functional outcome, defined as more than 80% of normal rotation of the forearm, with restoration of the normal amount and location of the radial bow. Additionally, they related the restoration of grip strength with appropriate restoration of the radial bow. Matthews and associates reported little significant loss of rotation with 10° of angulation; however, 20° of angulation
resulted in a statistically and clinically significant loss of forearm rotation.

Question 39:

Options:

Lower subscapular nerve
Suprascapular nerve at the spinoglenoid notch
Suprascapular nerve at the suprascapular notch
Axillary nerve

Correct Answer: Suprascapular nerve at the spinoglenoid notch

Explanation:

This athlete has a symptomatic posterior-superior labral tear, spinoglenoid notch cysts, and subsequent suprascapular nerve compression, as evidenced by the atrophy of the infraspinatus muscle on sagittal T1 MRI. The cyst is located at the spinoglenoid notch and is compressing the suprascapular nerve after it has innervated the supraspinatus but before innervation of the infraspinatus; hence, the atrophy of infraspinatus on examination and imaging. Compression of the suprascapular nerve at the suprascapular notch would lead to weakness and atrophy of both the supraspinatus and infraspinatus. The lower subscapular nerve innervates the teres major, as well as, with the upper subscapular nerve, the
subscapularis. The teres minor is innervated by the axillary nerve.

Question 40:

Overgrowth of a limb in a patient with neurofibromatosis type 1 (NF1) is most likely associated with the presence of

Options:

dural ectasia.
Lisch nodules.
juvenile xanthogranuloma.
malignant peripheral nerve sheath tumor.
plexiform neurofibroma.

Correct Answer: plexiform neurofibroma.

Explanation:

Question 41:

Options:

recurrent buckling with a probable meniscal tear.
limitation of motion with a delay in recovery.
a full return to activity with no limitations.
an improvement in overall performance.
an uneventful completion of the soccer season.

Correct Answer: recurrent buckling with a probable meniscal tear.

Explanation:

Question 42:

- A patient has a noncomminuted displaced fracture of the radial head with a distal radioulnar dissociation. What is the most appropriate treatment for the radial head?

Options:

Allograft Replacement
Radioulnar synostosis
Excision of the radial head
Open reduction and internal fixation
Silicone radial head replacement

Correct Answer: Open reduction and internal fixation

Explanation:

Question 43:

Figure 33 shows the CT scan of a 40-year-old man who injured his left shoulder while skiing. What structure is attached to the bony fragment?

Options:

Superior glenohumeral ligament
Anterior band of the inferior glenohumeral ligament
Middle glenohumeral ligament
Subscapularis tendon
Long head of the biceps tendon

Correct Answer: Anterior band of the inferior glenohumeral ligament

Explanation:

Question 44:

Options:

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

Correct Answer: Anatomic hip center with subtrochanteric shortening osteotomy

Explanation:

Question 45:

Options:

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

Correct Answer: No treatment is indicated at this time

Explanation:

Question 46:

Figures 20a and 20b show the sagittal and coronal T1-weighted MRI scans of a patient’s left knee. Abnormal findings include

Options:

enchondroma of the proximal tibia.
a bone bruise of the lateral femoral condyle.
a tear of the lateral collateral ligament.
a tear of the discoid lateral meniscus.
a physeal fracture of the proximal femur.

Correct Answer: a tear of the discoid lateral meniscus.

Explanation:

Question 47:

Options:

Excessive anteversion of the humeral component
Excessive anteversion of the glenoid component
Excessive posterior capsular laxity
Anterior capsular laxity
Use of an oversized humeral head

Correct Answer: Excessive posterior capsular laxity

Explanation:

Question 48:

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

Options:

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

Correct Answer: Acute grade II anterior talofibular ligament ankle sprain

Explanation:

Question 49:

-A likely candidate for treatment with a thoracic lumbosacral orthosis scoliosis brace is seen in

Options:

Figure 178a.
Figure 178b.
Figure 178c.
Figure 178d.
Figure 178e.

Correct Answer: Figure 178d.

Question 50:

Options:

Loss of reduction of the ulnar physis
Loss of reduction of the radial metaphysis
Physeal arrest of the distal radius
Physeal arrest of the distal ulna
Osteonecrosis of the ulnar epiphysis

Correct Answer: Physeal arrest of the distal ulna

Explanation:

Question 51:

Flexion-distraction injuries of the thoracolumbar spine are most frequently associated with injury to what organ system?

Options:

Neurologic
Pulmonary
Gastrointestinal
Vascular
Lymphatic

Correct Answer: Gastrointestinal

Explanation:

Question 52:

Options:

a non-weight-bearing short leg cast.
open reduction and internal fixation.
no weight bearing with motor exercises for 8 weeks.
debridement, curettage, and drilling.
an ankle brace or taping when participating in athletic activity.

Correct Answer: debridement, curettage, and drilling.

Explanation:

Question 53:

An osteoconductive bone graft material has which of the following properties?

Options:

It contains osteoblastic cells capable of direct bone formation.
It has the ability to stimulate recruitment and differentiation of mesenchymal stem cells.
It has the ability to recruit progenitor cells that can differentiate into osteoblastic cells.
It has the ability to permit ingrowth and sprouting of capillaries and perivascular tissue.
It prevents creeping substitution to allow graft incorporation.

Correct Answer: It has the ability to permit ingrowth and sprouting of capillaries and perivascular tissue.

Explanation:

Question 54:

The radiograph shown in Figure 27 shows measurement of what angle?

Options:

Hallux valgus
Distal metatarsal articular
Intermetatarsal
Sesamoid divergence
Angle of joint congruence

Correct Answer: Distal metatarsal articular

Explanation:

Question 55:

What nerve is most at risk during placement of the anterolateral portal in elbow arthroscopy?

Options:

Median
Ulnar
Radial
Posterior interosseous
Anterior interosseous

Correct Answer: Radial

Explanation:

Question 56:

Options:

Hyperextension casting of the thoracolumbar spine for 6 weeks
In situ posterior fusion with instrumentation
Posterior fusion with instrumentation, with sagittal plane correction
Posterior decompression, followed by posterior fusion with instrumentation, with sagittal plane correction
Anterior decompression and partial corpectomy, with anterior instrumentation

Correct Answer: Posterior fusion with instrumentation, with sagittal plane correction

Explanation:

DISCUSSION: The patient has a displaced burst fracture. Fusion with instrumentation has shown better results than casting alone. Posterior fusion with instrumentation, with sagittal plane correction, yields the best results. Decompression occurs indirectly with correction of the kyphosis. Anterior decompression is unnecessary.
REFERENCES: Lalonde F, Letts M, Yang JP, et al: An analysis of burst fractures of the spine in adolescents. Am J Orthop 2001;30:115-120.
Clark P, Letts M: Trauma to the thoracic and lumbar spine in the adolescent. Can J Surg 2001;44:337-345.
Been HD, Bouma GJ: Comparison of two types of surgery for thoraco-lumbar burst fractures: Combined anterior and posterior stabilization vs posterior instrumentation only. Acta Neurochir (Wien) 1999;141:349-357.

Question 57:

Options:

splinting and injections for carpal tunnel syndrome.
scaphoid excision and four-bone fusion.
proximal row carpectomy via dorsal and volar incisions.
MRI of the wrist.
carpal tunnel release.

Correct Answer: proximal row carpectomy via dorsal and volar incisions.

Explanation:

Question 58:

Osteoclastic bone resorption is stimulated primarily by what molecular interaction?

Options:

Parathyroid hormone (PTH)-osteoclasts
Interleukin-6 (IL-6) and IL-8
Receptor activator of nuclear factor kappa beta (RANK)-RANK ligand (RANKL)
Osteoprotegrin (OPG)-RANKL

Correct Answer: Receptor activator of nuclear factor kappa beta (RANK)-RANK ligand (RANKL)

Explanation:

Question 59:

Options:

physical therapy to stretch the tight structures.
a humeral rotational osteotomy.
anterior shoulder release and posterior muscle transfers.
anterior shoulder release.
shoulder fusion.

Correct Answer: a humeral rotational osteotomy.

Explanation:

Question 60:

- Which of the following surgical approaches to the hip is associated with the highest incidence of heterotopic ossification?

Options:

Ilioinguinal
Extended iliofemoral
Combined ilioinguinal and Kocher-Langenbeck (posterior)
Kocher-Langenbeck (posterior)
Kocher-Langenbeck (posterior) with trochanteric osteotomy

Correct Answer: Extended iliofemoral

Explanation:

Question 61:

Options:

Rim width
Rim length
Time from injury to repair
Use of a fibrin clot
Whether the tear occurred in the medial versus lateral meniscus

Correct Answer: Rim width

Explanation:

Question 62:

Options:

fixation of the lateral malleolus.
fixation of the medial malleolus.
fixation of the posterior malleolus.
all planned fixation is completed .

Correct Answer: all planned fixation is completed .

Explanation:

Discussion:
The radiographs reveal a trimalleolar ankle fracture dislocation with an associated distal tibiofibular syndesmotic disruption. Medial and lateral malleolar stabilization are consistently agreed upon. The decision to stabilize the posterior malleolus is more controversial. Posterior malleolar stabilization accomplishes the following:
Restores incisura competence thereby reducing the incidence of syndesmotic malreduction by creating containment
Assists in stabilizing the syndesmosis via the posterior inferior tibiofibular ligament, potentially limiting the need for additional syndesmotic stabilization
Maximizes the surface area for ankle joint loading
Enhances posterior translational stability of the talus
The traditional indication for stabilization of the posterior malleolus is based on fragment size. However, fracture orientation varies and makes evaluation of the fragment size challenging with a lateral radiograph alone. The three primary types include the posterolateral oblique, medial extension, and shell. Because of the additive syndesmotic stability which is gained through the deep deltoid ligament and medial malleolar fixation, the anterior talofibular ligament and lateral malleolar fixation, and the posterior inferior tibiofibular ligament and posterior malleolar fixation, syndesmotic stability should only be assessed after all other points of instability that are planned for fixation are fixed.
Syndesmotic instability should be assessed with direct manipulation on both the anteroposterior and lateral views with special attention to the lateral view. Syndesmotic reduction should be assessed either through open visualization or by comparing closed reduction parameters (clear space, overlap, and fibular position on the lateral view) with the patient’s contralateral side (assuming no injury). This is more effective than using population norms secondary to the two types of syndesmotic morphologies which create different absolute values for these parameters.

Question 63:

What is the main function of collagen found within articular cartilage?

Options:

Compressive properties
Tensile properties
Proteoglycan synthesis
Cartilage metabolism
Joint lubrication

Correct Answer: Tensile properties

Explanation:

Question 64:

Surgical restoration of sagittal balance of an adult spinal deformity will have which effect on outcome?

Options:

No effect
Improve leg-related symptoms but not back pain
Improve quality of life and back pain
Improve quality of life and leg-related symptoms

Correct Answer: Improve quality of life and back pain

Explanation:

DISCUSSION
The influence of sagittal balance on outcomes following fusion-based procedures for degenerative conditions of the lumbar spine has only recently been appreciated. Restoration of sagittal spinal balance improves low-back-pain outcomes and quality of life. Sagittal spinal balance has not been shown to relieve neurogenic claudication attributable to spinal stenosis.
RECOMMENDED READINGS
Li Y, Hresko MT. Radiographic analysis of spondylolisthesis and sagittal spinopelvic deformity. J Am Acad Orthop Surg. 2012 Apr;20(4):194-205. doi: 10.5435/JAAOS-20-04-194. Review. PubMed PMID: 22474089.
View Abstract at PubMed
Korovessis P, Repantis T, Papazisis Z, Iliopoulos P. Effect of sagittal spinal balance, levels of posterior instrumentation, and length of follow-up on low back pain in patients undergoing posterior decompression and instrumented fusion for degenerative lumbar spine disease: a multifactorial analysis. Spine (Phila Pa 1976). 2010 Apr 15;35(8):898-905. doi: 10.1097/BRS.0b013e3181d51e84. PubMed PMID: 20354466.
View
Abstract at PubMed
CLINICAL SITUATION FOR QUESTIONS 99 AND 100
Figures 99a and 99b are MR images of a 59-year-old man with a history of intravenous (IV) drug abuse who arrives at the emergency department with malaise and fever. Upon admission, the patient's temperature is 38.9°C, his white blood cell count is 17000/µL (reference range [rr], 4500-11000/µL), his erythrocyte sedimentation rate is 98 mm/h (rr, 0-20 mm/h), and his C-reactive protein level is 45 mg/L (rr, 0.08-3.1 mg/L). He is admitted to the medical service to evaluate the source of his fevers. On hospital day 1, the patient reports weakness in his left arm and leg. Blood cultures are positive for methicillin-resistant Staphylococcus aureus.
A B

Question 65:

Options:

Medial to the bicipital groove and pectoralis major tendon
Medial to the bicipital groove and lateral to the pectoralis major tendon
Lateral to the bicipital groove and pectoralis major tendon
Lateral to the bicipital groove and medial to the pectoralis major tendon
In the bicipital groove

Correct Answer: Lateral to the bicipital groove and pectoralis major tendon

Explanation:

DISCUSSION: The pectoralis major tendon inserts lateral to the biceps tendon, which runs in the bicipital groove. The primary vascular supply of the articular surface of the humeral head is derived from the anterior circumflex humeral artery, which continues into the arcuate artery once it enters the bone. The entry point is on the anterolateral aspect of the humerus just medial to the greater tuberosity within the bicipital groove. To avoid compromising circulation, the blade plate should be placed lateral to the bicipital groove and pectoralis major tendon insertion.
REFERENCES: Loebenberg M, Plate AM, Zuckerman J: Osteonecrosis of the humeral head. Instr Course Lect 1999;48:349-357.
Gerber C, Schneeberger AG:
The arterial vascularization of the humeral head: An anatomical study. J Bone Joint Surg Am 1990;72:1486-1494.

Question 66:

Compared with retention of the native patella in primary total knee arthroplasty, routine patellar resurfacing is associated with

Options:

no patellar complications.
an increased occurrence of anterior knee pain.
a reduced patellar fracture rate.
a reduced risk for revision surgery.

Correct Answer: a reduced risk for revision surgery.

Explanation:

Question 67:

Options:

Pelvic incidence
Slip angle
Sacral inclination
Lumbosacral joint angle
Sagittal rotation

Correct Answer: Slip angle

Explanation:

Question 68:

A subtrochanteric femur fracture in which the lesser trochanter is intact is associated with what deformity?

Options:

Adduction and extension of the proximal fragment
Adduction and flexion of the proximal fragment
Abduction and extension of the proximal fragment
Abduction and flexion of the proximal fragment
Predominantly internal rotation of the proximal fragment

Correct Answer: Abduction and flexion of the proximal fragment

Explanation:

Question 69:

A B Figures 19a and 19b are the CT scans of an 18-year-old man who was a restrained driver in a rollover motor vehicle collision. What was the primary mechanism of injury?

Options:

Axial load
Rotation
Extension
Distraction

Correct Answer: Distraction

Explanation:

Question 70:

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 71:

A 28-year-old painter has had increasing pain in his hand and forearm after sustaining a paint injection wound to the tip of his left index finger 24 hours ago. Management should consist of

Options:

hospital admission and IV antibiotics.
emergent surgical debridement.
oral antibiotics, splinting, and elevation.
nonsteroidal anti-inflammatory drugs and splinting.
oral antibiotics and a tetanus shot.

Correct Answer: emergent surgical debridement.

Explanation:

Question 72:

Options:

Intracompartmental pressure monitoring
Immobilization of the knee in a flexed position
Fasciotomy of the thigh
MRI scan of the femur This athlete has experienced a quadriceps contusion with hemorrhage and swelling into the anterior compartment of the thigh. Initial treatment for these injuries is immobilization of the knee in flexion to reduce the amount of bleeding into the anterior compartment. Rest and anti-inflammatory medication may be used in the rehabilitation process but should not take the place of immobilization in flexion. The compartments are soft and therefore, there is no indication for fasciotomy. MRI scan of the femur may demonstrate hematoma in the anterior thigh compartment but is not required to make the diagnosis.

Correct Answer: Immobilization of the knee in a flexed position

Explanation:

Question 73:

Options:

Nonoperative treatment with a sling and swathe for six weeks
Nonoperative treatment with immediate active range of motion of the shoulder
Closed reduction in the emergency room
Open reduction and percutaneous pinning with thoracic surgery back-up
Open reduction and ligament reconstruction with thoracic surgery back-up

Correct Answer: Nonoperative treatment with a sling and swathe for six weeks

Explanation:

Question 74:

Options:

Vigorous physical therapy
Manipulation under anesthesia
Arthroscopic capsular release
Hemiarthroplasty
Arthroscopic capsular plication

Correct Answer: Hemiarthroplasty

Explanation:

DISCUSSION: Appropriate treatment is based on multiple considerations, which include the chronicity of the dislocation, the amount of humeral head involvement, the medical condition, and functional limitations of the patient. It has been shown that shoulder arthroplasty for locked posterior dislocation provides pain relief and improved motion. Transfer of the lesser tuberosity with its attached subscapularis tendon into the defect is recommended for anteromedial humeral defects that are smaller than approximately 40% of the joint surface. Subscapularis transfer as described by McLaughlin and the modification thereof later described by Hawkins and associates in which the lesser tuberosity is transferred into the defect, have yielded good results if the defect is less than 40% of the humeral head. Prosthetic replacement is preferred for larger defects. If the dislocation is less than 3 weeks old and has less than 25% of humeral head involvement, closed reduction with the patient under general anesthesia should be attempted and the stability assessed by internally rotating the arm. If the arm can be safely internally rotated to the abdomen, then 6 weeks of immobilization in an orthosis that maintains the shoulder in slight extension and external rotation can yield a good result. If the dislocation has been present for more than 3 weeks, closed reduction becomes exceedingly difficult.
REFERENCES: Gerber C, Lambert SM: Allograft reconstruction of segmental defects of the humeral head for the treatment of chronic locked posterior dislocation of the shoulder. J Bone Joint Surg Am 1996;78:376-382.
Spencer EE Jr, Brems JJ: A simple technique for management of locked posterior shoulder dislocations: Report of two cases. J Shoulder Elbow Surg 2005;14:650-652.
Sperling JW, Pring M, Antuna SA, et al: Shoulder arthroplasty for locked posterior dislocation of the shoulder. J Shoulder Elbow Surg 2004;13:522-527.
Hawkins RJ, Neer CS II, Pianta RM, et al: Locked posterior dislocation of the shoulder. J Bone Joint Surg Am 1987;69:9-18.
McLaughlin HL: Posterior dislocation of the shoulder. J Bone Joint Surg Am 1952;34:584-590.

Question 75:

Options:

Spring ligament reconstruction
Lateral column lengthening
Medial-displacing calcaneal osteotomy
Medial cuneiform opening-wedge osteotomy

Correct Answer: Medial-displacing calcaneal osteotomy

Explanation:

Question 76:

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

Options:

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

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

Explanation:

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

Question 77:

Figure 39 shows the radiograph of a 4-month old infant who has been undergoing weekly casting since birth for a congenital equinovarus deformity. Management should now consist of

Options:

surgical correction.
continued casting.
botulinum toxin injection into the gastrocnemius-soleus complex.
an ankle-foot orthosis.
observation with no further treatment.

Correct Answer: surgical correction.

Explanation:

DISCUSSION: The radiograph shows the development of a rocker-bottom foot deformity. A rocker-bottom foot occurs in the treatment of clubfoot when casting is continued in the presence of a very tight gastrocnemius-soleus complex and an uncorrected hindfoot. While there are some preliminary reports on using Botox injection and continued casting for the equinus deformity, most authors recommend posterior or posterior medial release. Percutaneous tenotomy has been recently recommended with the resurgence of the Ponsetti technique.
REFERENCES: Lehman WB, Atar D: Complications in the management of talipes equinovarus, in Drennan JC (ed): The Child’s Foot and Ankle. New York, NY, Raven Press, 1992,
pp 135-136.
Herring JA: Tachdjian’s Pediatric Orthopedics, ed 4. Philadelphia, PA, WB Saunders, 2002,
pp 927-935.
Tachdjian MO: Pediatric Orthopedics, ed 2. Philadelphia, PA, WB Saunders, 1990,
pp 2461-2564.

Question 78:

Options:

The examiner brings a finger from medial to lateral across the antecubital fossa, feeling for a cord-like structure.
The examiner brings a finger from lateral to medial across the antecubital fossa, feeling for a cord-like structure.
With the elbow flexed to 90°and the forearm pronated, the examiner resists patient supination, evaluating for pain at the bicipital groove.
With the patient’s arm elevated to 90° of forward flexion, the elbow extended, and the forearm supinated, the examiner resists elevation distal to the elbow, evaluating for pain at the bicipital groove.

Correct Answer: The examiner brings a finger from lateral to medial across the antecubital fossa, feeling for a cord-like structure.

Explanation:

EXPLANATION:

Question 79:

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 80:

-Figure 235 is the radiograph of a 75-year-old woman who is seen in the emergency department following a low-energy fall. What is the most appropriate treatment based on her radiographic findings?

Options:

Perform a biopsy of the lesion
Stabilize with an intramedullary nail
Initiate immediate bisphosphonate therapy
Treat with chemotherapy followed by wide resection
Obtain a chest CT scan, urine protein electrophoresis, and serum protein electrophoresis

Correct Answer: Stabilize with an intramedullary nail

Question 81:

A Trendelenburg gait is most likely to be seen in association with

Options:

a central disk herniation at L3-L4.
an ipsilateral paracentral disk herniation at L3-L4.
an ipsilateral paracentral disk herniation at L4-L5.
an ipsilateral paracentral disk herniation at L5-S1.
an ipsilateral far lateral disk herniation at L4-L5.

Correct Answer: an ipsilateral paracentral disk herniation at L4-L5.

Explanation:

Question 82:

Which of the following tissues used for anterior cruciate ligament (ACL) reconstruction has the highest maximum load to failure?

Options:

Allograft ACL
Bone-patellar tendon-bone with a width of 10 mm
Fascia lata with a width of 15 mm
Central quadriceps tendon with a width of 15 mm
Quadruple semitendinosus and gracilis tendons

Correct Answer: Quadruple semitendinosus and gracilis tendons

Explanation:

Question 83:

Options:

core decompression.
a vascularized fibula graft.
intraosseous steroid injection.
total hip replacement.
protected weight bearing.

Correct Answer: protected weight bearing.

Explanation:

Question 84:

Options:

Posterior decompression
Posterior interbody arthrodesis
Posterior decompression and in situ arthrodesis
Posterior decompression and instrumented arthrodesis
Anterior and posterior arthrodesis

Correct Answer: Posterior decompression and instrumented arthrodesis

Explanation:

Question 85:

Options:

follow-up with repeat radiographs in 6 months.
brace treatment.
posterior spinal fusion with instrumentation.
anterior and posterior spinal fusion with instrumentation.
anterior spinal fusion with instrumentation.

Correct Answer: anterior and posterior spinal fusion with instrumentation.

Explanation:

Question 86:

Which of the following findings is most prognostic for the ability of a young child with cerebral palsy to walk?

Options:

Ability to sit independently by age 2 years
Ability to creep by age 2 years
Ability to roll by age 2 years
Pattern of cerebral palsy (quadriplegia, diplegia, hemiplegia)
Type of motor dysfunction (spastic, ataxic, dyskinetic, hypotonic)

Correct Answer: Ability to sit independently by age 2 years

Explanation:

DISCUSSION: Several studies have shown that sitting ability by age 2 years is highly prognostic of walking. Molnar and Gordon reported that children not sitting independently by age 2 years had a poor prognosis for walking. Wu and associates reported that children sitting without support by age 2 years had an odds ratio of 26:1 of walking compared with those unable to sit. This was far higher than the odds ratios for cerebral palsy location, motor dysfunction, crawling, creeping, scooting, or rolling.
REFERENCES: Molnar GE, Gordon SU: Cerebral palsy: Predictive value of selected clinical signs for early prognostication of motor function. Arch Phys Med Rehabil 1976;57:153-158.
Wu YW, Day SM, Strauss DJ, et al: Prognosis for ambulation in cerebral palsy: A population-based study. Pediatrics 2004;114:1264-1271.

Question 87:

Options:

Osteolysis because of polyethylene debris
Spot weld
Osteosclerotic pedestal
Cement fragmentation
Allergic reaction to titanium

Correct Answer: Osteolysis because of polyethylene debris

Explanation:

Question 88:

Options:

Supplemental internal fixation
Primary ankle arthrodesis
Nonsurgical treatment to avoid infection
Early bone grafting because of poor bone quality
Early mobilization and weight bearing to minimize stiffness

Correct Answer: Supplemental internal fixation

Explanation:

Question 89:

Options:

McCune-Albright syndrome
Neurofibromatosis, type I (NF-1)
Neurofibromatosis, type II (NF-2)
Paget’s disease
Ollier’s disease

Correct Answer: McCune-Albright syndrome

Explanation:

Question 90:

What is the most common malignant bone tumor seen in patients with multiple hereditary exostosis?

Options:

Dedifferentiated chondrosarcoma
Mesenchymal chondrosarcoma
Secondary chondrosarcoma
Clear cell chondrosarcoma
Periosteal osteosarcoma

Correct Answer: Secondary chondrosarcoma

Explanation:

Question 91:

Options:

Splinting, admission, and frequent neurovascular checks
Cylinder cast and discharge
Emergent knee arthroscopy
Four-compartment calf fasciotomy
Non-weight-bearing, a knee immobilizer, and follow-up in 1 week

Correct Answer: Splinting, admission, and frequent neurovascular checks

Explanation:

Question 92:

Options:

external fixation of the forearm fracture and functional bracing of the humeral shaft fracture.
external fixation of both fractures.
open reduction and internal fixation of both fractures.
open reduction and the internal fixation of the forearm fracture and functional bracing of the humeral shaft fracture.
application of a long arm cast.

Correct Answer: open reduction and internal fixation of both fractures.

Explanation:

Question 93:

Options:

a bone scan and thallium scan.
a regional lymph node and bone marrow biopsy.
MRI of the brain.
intravenous pyelogram and renal ultrasound.
parathyroid hormone and serum calcium levels.

Correct Answer: a regional lymph node and bone marrow biopsy.

Explanation:

Question 94:

Options:

High tibial osteotomy
Total knee replacement
Unicondylar knee replacement
Arthroscopic partial meniscectomy

Correct Answer: Total knee replacement

Explanation:

Question 95:

Which of the following factors has been shown to increase mortality in poly-trauma patients with severe head injuries?

Options:

Delayed fixation of fractures
Decreased intracranial pressure
Intra-abdominal injury
Intra-operative hypotension
Decreased platelet count

Correct Answer: Delayed fixation of fractures

Explanation:

Question 96:

Options:

Physical therapy for range-of-motion exercises
Aspiration for possible infection
MRI to evaluate for possible rotator cuff tear
Sling immobilization and reevaluation in 4 weeks
Duplex ultrasound for possible upper extremity deep venous thrombosis

Correct Answer: Physical therapy for range-of-motion exercises

Explanation:

Question 97:

- A 50-year-old alcoholic man has erythema and swelling in his entire dominant upper extremity. He has a WBC of 15,000/mm3, a temp of 101 oF (38.3 oC), and a blood pressure of 90/60 mm Hg. After hemodynamic stabilization, the cellulitic forearm is longitudinally incised dorsally and volarly. The forearm muscles are normal in appearance; however, the subcutaneous fat is necrotic. A culture will most likely reveal

Options:

Bacteroides
coli
Staph. aureus
group A streptococcus
Clostridium perforingens

Correct Answer: group A streptococcus

Explanation:

Question 98:

Options:

Urgent admission to the hospital for surgical intervention
Immediate MRI of the lumbar spine as an outpatient
Anti-inflammatory medications and activity modification
Caudal epidural steroid injection
Electromyography

Correct Answer: Anti-inflammatory medications and activity modification

Explanation:

Question 99:

03 Which of the following findings is the best indication for the use of temporary external fixation of a femoral shaft fracture?

Options:

Type IIIA open fracture
back to this question next question
Hemodynamic instability
Segmental fracture
Distal one third fracture
Ipsilateral tibial shaft fracture 33.03

Correct Answer: back to this question next question

Explanation:

These days, femoral shaft fractures at Tulane / Charity are commonly encountered by orthopaedic residents on the night-float team.
Despite the presence of a well-rested 4th year surgeon, definitive orthopaedic fixation is not always the correct answer for each trauma patient.
Tulane defines “Orthopaedic Tunnel Vision” as a condition commonly associated with a young MD at the Bulldog without a proper
wing-man, trying to make advances on the wrong patron due to his relatively easy 80-hour work week schedule and a few too many refined hops.
Skeletal Trauma (p. 1967) describes “Orthopaedic Tunnel Vision” as looking at the orthopaedic injury without considering the
patient’s injury in general. Femoral shaft fractures are typically high energy injuries which often do not occur in isolation. In these fractures, it is particularly important to not have tunnel vision.
Indications for temporary bridging external fixation includes hemodynamic instability
(ans. 2), acidosis, hypothermjia, hypoxemia, coagulopathy, sepsis or severely contaminated soft tissues that cannot be adequately debrided. Definitive fixation is performed after the general surgical and medical issues have resolved.
The other answer choices, including the type IIIA open fracture are not contraindications to definitive fixation in themselves (typically IM nailing—antegrade or retrograde).

Question 100:

- A 15-year-old dancer who has had brief episodes of back pain over the past 2 years now reports a 3 month history of low back pain and a decreased tolerance for dance. Figure 22a-c show flexion and extension x-rays and CT scan. She reports no leg pain, nor any bowel or bladder difficulties. Management should now consist of

Options:

Post spinal fusion from L5to S1
Primary repair with an iliac bone graft
Post spinal fusion of L4-5
A pantaloon body cast and 6 weeks of bed rest
Rest, NSAIDS, and limited dancing

Correct Answer: Rest, NSAIDS, and limited dancing

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

Orthopedic Surgery Board Review MCQs: Spine, Trauma, & Foot & Ankle Part 215

Key Takeaway

About This Board Review Set

How to Use the Interactive Quiz

Topics Covered in Part 215

Sample Questions from This Set

Why Active MCQ Practice Works

Chapter Index