Orthopedic Board Review MCQs: OITE & AAOS Part 146

About This Board Review Set

This is Part 146 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 146

This module focuses heavily on: Arthroplasty, Elbow, Hip, Infection, Trauma.

Sample Questions from This Set

Sample Question 1: A 58-year-old man reports a 2-month onset of groin pain with no history of trauma. Examination reveals that range of motion of the hip is mildly restricted, and he has pain with both weight bearing and at rest. An MRI scan is shown in Figur...

Sample Question 2: When an acute infection of a total elbow arthroplasty is managed with irrigation and debridement, which of the following organisms is associated with the highest risk of persistent infection?...

Sample Question 3: 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?...

Sample Question 4: Figure 56 is the radiograph of an otherwise healthy 3-year-old boy who fell and sustained the isolated injury shown. What is the best treatment modality?...

Sample Question 5: A patient who has recalcitrant medial plantar heel pain and pain directly over the medial side of the heel undergoes open release of the plantar fascia. After releasing a portion of the plantar fascia, the deep fascia of the abductor halluc...

Why Active MCQ Practice Works

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

Comprehensive 100-Question Exam

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Question 1

A 58-year-old man reports a 2-month onset of groin pain with no history of trauma. Examination reveals that range of motion of the hip is mildly restricted, and he has pain with both weight bearing and at rest. An MRI scan is shown in Figure 20. Treatment should consist of

Explanation

DISCUSSION: The MRI findings show highly increased signal through the entire femoral head and neck on STIR imaging, diagnostic of transient osteoporosis of the femoral head. This disease entity can be seen in middle-aged men, and should be treated nonsurgically. The natural history is that of self-resolution.
REFERENCES: Guerra JJ, Steinberg ME: Distinguishing transient osteoporosis from avascular necrosis of the hip. J Bone Joint Surg Am 1995;77:616-624.
Urbanski SR, de Lange EE, Eschenroeder HC Jr: Magnetic resonance imaging of transient osteoporosis of the hip: A case report. J Bone Joint Surg Am 1991;73:451-455.

Question 2

When an acute infection of a total elbow arthroplasty is managed with irrigation and debridement, which of the following organisms is associated with the highest risk of persistent infection?

Explanation

DISCUSSION: Salvage of a total elbow arthroplasty is possible with early aggressive management of acute infection (symptoms for less than 30 days) with serial irrigation and debridement and antibiotic bead placement. This form of treatment is indicated when there are no radiographic or intraoperative signs of loosening. However, successful treatment is largely dependent on the organism. Staphylococcus epidermidis is associated with persistent infection because it is an encapsulating organism, and it is best treated with implant removal and

IV antibiotics.
REFERENCES: Yamaguchi K, Adams RA, Morrey BF: Infection after total elbow arthroplasty. J Bone Joint Surg Am 1998;80:481-491.
Schoifet SD, Morrey BF: Treatment of infection after total knee arthroplasty by debridement with retention of the components. J Bone Joint Surg Am 1990;72:1383-1390.

Question 3

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 4

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

Explanation

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

Question 5

A patient who has recalcitrant medial plantar heel pain and pain directly over the medial side of the heel undergoes open release of the plantar fascia. After releasing a portion of the plantar fascia, the deep fascia of the abductor hallucis muscle is released to relieve pressure on which of the following structures?

Explanation

DISCUSSION: The deep fascia of the abductor hallucis muscle is released to relieve pressure on the first branch of the lateral plantar nerve. The tibial nerve lies more proximal to this area. The medial plantar nerve has already passed dorsally and medially, while the sural nerve lies on the lateral side of the foot. The flexor hallucis brevis muscle lies deep to the plantar fascia, not the abductor fascia.
REFERENCES: Baxter DE, Pfeffer GB: Treatment of chronic heel pain by surgical release of the first branch of the lateral plantar nerve. Clin Orthop 1992;279:229-236.
Davies MS, Weiss GA, Saxby TS: Plantar fasciitis: How successful is surgical intervention? Foot Ankle Int 1999;20:803-807.

Question 6

Figures 15a through 15c show the radiographs of a 23-year-old football player who was injured when another player fell on his flexed and planted foot. He reports severe pain in the midfoot with a feeling of numbness on the dorsum of the foot, and he is unable to bear weight on the limb. Examination reveals mild swelling. Management should consist of

Explanation

DISCUSSION: Myerson and associates studied the outcomes of 19 patients with tarsometatarsal joint injuries during athletic activity. Injuries were classified as first- or second-degree sprains of the tarsometatarsal joint or a third-degree sprain with diastasis between the metatarsals or cuneiforms. Poor functional results were seen in those with a delay in diagnosis and with inadequate treatment. For patients with third-degree sprains, poor results were obtained with nonsurgical management. These patients required open reduction and internal fixation for optimal return to function. The anatomic reduction is critical to the outcome; therefore, open reduction is preferred.
REFERENCES: Baxter DE: The Foot and Ankle in Sport, ed 1. St Louis, MO, Mosby, 1995,

pp 107-123.
Curtis MJ, Myerson M, Szura B: Tarsometatarsal joint injuries in the athlete. Am J Sports Med 1993;21:497-502.
Kuo RS, Tejwani NC, DiGiovanni CW, et al: Outcome after open reduction and internal fixation of Lisfranc joint injuries. J Bone Joint Surg Am 2000;82:1609-1618.
Thompson MC, Mormino MA: Injury to the tarsometatarsal joint complex. J Am Acad Orthop Surg 2003;11:260-267.

Question 7

A 6-year-old boy has leg pain. A radiograph, MRI, CT, and bone scans, and a biopsy specimen are shown in Figures 14a through 14e. What is the most likely diagnosis?

Explanation

DISCUSSION: From an imaging point of view, all of the diagnoses are possible. Biopsy results and cultures are necessary to make the diagnosis. The biopsy specimen shows inflammatory cells and necrotic bone, consistent with osteomyelitis.
REFERENCES: Fletcher BD, Hanna SL: Pediatric musculoskeletal lesions simulating neoplasms. Magn Reson Imaging Clin N Am 1996;4:721-747.
Hanna SL, Fletcher BD, Kaste SC, Fairclough DL, Parham DM: Increased confidence of diagnosis of Ewing sarcoma using T2-weighted MR images. Magn Reson Imaging 1994;12:559-568.

Question 8

Following ankle arthroscopy performed through a posterolateral portal, a patient notes numbness on the lateral half of the heel pad of the foot. What is the most likely injured structure?

Explanation

DISCUSSION: The lateral calcaneal nerve is a branch of the sural nerve that runs along the lateral border of the Achilles tendon to innervate the lateral heel pad. Ankle arthroscopy involves posterior portals that hug the Achilles tendon to avoid the main trunks of the sural nerve and tibial nerve; however, the lateral calcaneal branch remains potentially vulnerable. The first branch of the lateral plantar nerve is actually a medial structure that partially innervates the plantar fascia and the abductor digiti quinti. The deep peroneal nerve is anterior to the ankle.
REFERENCES: Sitler DF, Amendola A, Bailey CS, et al: Posterior ankle arthroscopy:

An anatomic study. J Bone Joint Surg Am 2002;84:763-769.
Sarrafian SK: Anatomy of the Foot and Ankle, Descriptive, Topographic, Functional, ed 2. Philadelphia, PA, JB Lippincott, 1993, p 361.

Question 9

Figure 12 shows the radiograph of a 15-year-old boy with cerebral palsy who has pain at the first metatarsophalangeal joints. He is a community ambulator. Management consisting of accommodative shoes has failed to provide relief. What is the treatment of choice?

Explanation

DISCUSSION: While other surgeries have provided some success, first metatarsophalangeal joint arthrodesis has the highest overall success rate compared to other surgeries in ambulatory and nonambulatory children with cerebral palsy. The recurrence rate is unacceptably high with the other procedures listed above. In contrast, neurologically normal children are amenable to osteotomies and soft-tissue procedures.
REFERENCES: Davids JR, Mason TA, Danko A, et al: Surgical management of hallux valgus deformity in children with cerebral palsy. J Pediatr Orthop 2001;21:89-94.
Jenter M, Lipton GE, Miller F: Operative treatment for hallux valgus in children with cerebral palsy. Foot Ankle Int 1998;19:830-835.

Question 10

A 52-year-old man who was a former high school pitcher now reports loss of elbow flexion and extension with pain at the extremes of motion. Nonsurgical management has failed to provide relief. Examination reveals movement from 50 degrees to 110 degrees and is painful only at the limits of motion. A radiograph is shown in Figure 12. Treatment should consist of

Explanation

DISCUSSION: Based on the history, examination, and radiograph, the patient has typical degenerative arthritis of the elbow. This condition is found almost exclusively in men, and there is almost universally a history of repetitive heavy use or overuse of the elbow. Patients report pain at terminal extension and usually have a flexion contracture. Radiographs reveal osteophytes on the coronoid and olecranon and in the coronoid and olecranon fossae. The osteophytes are often associated with loose bodies that sometimes are attached to the soft tissues. Treatment should consist of removal of all loose bodies and impinging osteophytes using open technique or by arthroscopy. The capsular contractures should be released at the same time.
REFERENCES: Kasser JR (ed): Orthopaedic Knowledge Update 5. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1996, pp 283-294.
Morrey BF: Primary degenerative arthritis of the elbow: Treatment by ulnohumeral arthroplasty. J Bone Joint Surg Br 1992;74:409-413.
Redden JF, Stanley D: Arthroscopic fenestration of the olecranon fossa in the treatment of osteoarthritis of the elbow. Arthroscopy 1993;9:14-16.
O’Driscoll SW: Elbow arthritis: Treatment options. J Am Acad Orthop Surg 1993;1:106-116.

Question 11

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

Explanation

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

Question 12

A 16-year-old girl has had anterior leg pain and a mass for the past 8 months. Figures 2a and 2b show a radiograph and an H & E histologic specimen. Which of the following disorders is believed to be a precursor of this lesion?

Explanation

DISCUSSION: The radiograph and pathology are consistent with adamantinoma. While the mechanism underlying adamantinoma has not been identified, it is believed to be closely related to osteofibrous dysplasia, which may represent a precursor. The other diagnoses are not known to give rise to adamantinoma.
REFERENCE: Springfield DS, Rosenberg AE, Mankin HJ, et al: Relationship between osteofibrous dysplasia and adamantinoma. Clin Orthop 1994;309:234-244.

Question 13

View Abstract at PubMed Figures 87a and 87b are sagittal and coronal MR images of the affected elbow of a 36-year-old man who has a history of painful mechanical symptoms in his dominant arm when extending his elbow in full supination. What is the most likely cause of his painful snapping? A B

Explanation

DISCUSSION
The MRI studies show a radiocapitellar plica. This anomalous structure has been associated with symptomatic snapping. Lacertus fibrosis contracture will not cause painful snapping. An intra-articular pathology such as loose bodies is not present on these imaging studies. Olecranon fossa impingement causes posterior pain in extension and is not shown in the images.
RECOMMENDED READINGS
Antuna SA, O'Driscoll SW. Snapping plicae associated with radiocapitellar chondromalacia. Arthroscopy. 2001 May;17(5):491-5. PubMed 11337715. View Abstract at PubMed
Ruch DS, Papadonikolakis A, Campolattaro RM. The posterolateral plica: a cause of refractory lateral elbow pain. J Shoulder Elbow Surg. 2006 May-Jun;15(3):367-70. PubMed PMID: 16679240. View Abstract at PubMed

Question 14

Figures 1 and 2 are the MR arthrogram images of a 20-year-old right-hand dominant collegiate basketball player who sustained an initial shoulder dislocation 1 year ago. In the month prior to presentation, he dislocated his shoulder two more times. Each time it occurred when going up for a rebound and an opponent grabbed the ball from behind him, hyperextending his shoulder. Physical examination demonstrates full range of motion, absence of atrophy, a positive apprehension sign and relocation test, and a positive Kim test. What is the best next step?

Explanation

The mechanism of injury/dislocation is most consistent with anterior glenohumeral joint instability. The axial cuts of the MR arthrogram reveals an anteroinferior labral tear, as well as a posterior labral tear. A Hill-Sachs lesion is also consistent with anterior glenohumeral joint instability. At the time of examination under anesthesia, this patient exhibited 2+ anterior and 2+ posterior glenohumeral joint instability. Patients with pan-labral tears and 270° tears can be challenging to diagnose, because patients can report anterior or posterior shoulder instability alone. The
physical examination and advanced imaging in these patients are crucial in directing appropriate treatment.

Question 15

In a locking plate screw construct, axial forces are borne by which of the following?

Explanation

In a traditional plate system, fracture security depends on the friction between the plate and the underlying bone. Bicortical fixation will decrease the toggle and improve stability. Locking plates absorb axial forces transmitted from the screws. Such plates do not require plate compression against the bone, thus preserving periosteal blood supply.

Question 16

An 18-year-old high school football player sustains a left posterior hip dislocation that is reduced in the emergency department under IV sedation. Postreduction radiographs reveal a concentric reduction with no evidence of fracture or loose bodies within the joint. What is the most common complication of hip dislocations?

Explanation

DISCUSSION: Traumatic dislocation of the hip in sports injuries is uncommon, and 85% to 92% occur in a posterior direction. In dislocations without fractures, osteonecrosis is the most common complication occurring in 10% to 20% of patients. MRI should be performed at 3 months postreduction to rule out osteonecrosis. Nerve injuries are rare in this setting, and recurrent dislocations are unusual without acetabular fractures. Chondrolysis has been reported as a rare occurrence.
REFERENCES: Anderson K, Strickland S, Warren R: Hip and groin injures in athletes. Am J Sports Med 2001;29:521-533.
Koval KJ (ed): Orthopaedic Knowledge Update 7. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 407-416.

Question 17

Which of the following factors is associated with failure of arthroscopic excision of the distal clavicle?

Explanation

DISCUSSION: Uneven resection of bone, typically leaving a retained posterolateral corner of the distal clavicle, can lead to failure of arthroscopic distal clavicle excision. The amount of bone resected, the gender of the patient, or the diagnosis (osteoarthritis versus osteolysis) does not appear to affect the results.
REFERENCE: Flatow EL, Duralde XA, Nicholson GP, Pollock RG, Bigliani LU: Arthroscopic resection of the distal clavicle with a superior approach. J Shoulder Elbow Surg 1995;4:41-50.

Question 18

A 10-year-old child with cerebral palsy undergoes bilateral hamstring lengthening for severe knee flexion contractures, and knee immobilizers are applied postoperatively. Examination at the initial postoperative check 2 hours after surgery reveals that she can dorsiflex her toes on the right foot, but not on the left foot. The physician should now

Explanation

DISCUSSION: Children with cerebral palsy are often difficult to examine. However, this patient clearly has a peroneal nerve deficit, most likely from the acute stretch after the hamstring lengthening. The nerve has the best chance of recovery if it is relaxed by flexing the knee. Once the nerve has recovered, gradual knee extension can be accomplished.
REFERENCES: Aspden RM, Porter RW: Nerve traction during correction of knee flexion deformity: A case report and calculation. J Bone Joint Surg Br 1994;76:471-473.
Heydarian K, Akbarnia BA, Jabalameli M, Tabador K: Posterior capsulotomy for the treatment of severe flexion contractures of the knee. J Pediatr Orthop 1984;4:700-704.

Question 19

Communication breakdown is the leading cause of which of the following?

Explanation

Communication failures are the leading cause of wrong side surgeries, medication errors and diagnostic delays.
Poor communication sets up environments in which medical errors can take place. Per the Joint Commission, medical errors may be the among the top 10 causes of death in the United States. Establishing open lines of communication is critical to reduce the risk of error and enhance patient safety.
Gandhi et al. designed a framework to study missed or delayed diagnoses and their causes. The most significant factors contributing to errors were poor handoffs, failures in judgment, failures in memory and failures in knowledge.
O’Daniel et al. review the importance of professional communication and collaborative team efforts. They note that patient safety is at risk when poor communication is in place. The leading cause for medication errors, treatment delays and wrong-site surgeries is communication failure.
Illustration A shows the leading causes of death in the United States. This includes “preventable errors” as a cause.
Incorrect Answers:

Question 20

A 35-year-old man who is an avid weight lifter competing in local tournaments reports new onset pain and loss of motion in his dominant right shoulder. Examination reveals joint line tenderness, active elevation to 100 degrees, and external rotation to 10 degrees. His contralateral shoulder reveals 170 degrees forward elevation and 50 degrees external rotation. Radiographs are shown in Figures 46a and 46b. What is the next most appropriate step in management?

Explanation

DISCUSSION: New onset pain and stiffness in the young arthritic shoulder is a difficult problem to treat. Initial management should be aimed at reducing pain and improving motion in all planes. This patient’s activities and age preclude a shoulder arthroplasty at this time. If nonsurgical management fails to provide relief, then arthroscopic debridement and capsular release may be beneficial.
REFERENCES: Norris TR (ed): Orthopaedic Knowledge Update: Shoulder and Elbow 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 257-266.
Skedros JG, O’Rourke PJ, Zimmerman JM, et al: Alternatives to replacement arthroplasty for glenohumeral arthritis, in Iannotti JP, Williams GR (eds): Disorders of the Shoulder: Diagnosis and Management. Philadelphia, PA, Lippincott Williams & Wilkins, 1999, pp 485-499.

Question 21

Figures 20a and 20b show the radiographs of an obese 15-year-old boy who has severe left groin pain and is unable to bear weight following a minor injury. Treatment should consist of

Explanation

DISCUSSION: The radiographs and history are consistent with an acute unstable slipped capital femoral epiphysis. Aronson and Loder documented an increased rate of osteonecrosis associated with manipulative reduction. They recommended bed rest with skin traction to allow the synovitis to resolve, followed by in situ pinning. They noted, however, that many of these slips reduced with anesthesia and positioning on a fracture table. Biomechanic studies have shown a slight increased resistance to shear stress when two screws are used, but it is unknown if this is significant in the clinical setting. Open epiphyseodesis does not provide postoperative stability; therefore, adjunctive fixation or immobilization is required. Numerous studies have noted the inadvisability of using multiple screws. Casting has a high rate of complications, including chondrolysis and progression of the slip.
REFERENCES: Aronson DD, Loder RT: Treatment of the unstable (acute) slipped capital femoral epiphysis. Clin Orthop 1996;322:99-110.
Karol LA, Doane RM, Cornicelli SF, Zak PA, Haut RC, Manoli A II: Single versus double screw fixation for treatment of slipped capital femoral epiphysis: A biomechanical analysis. J Pediatr Orthop 1992;12:741-745.
Stanitski CL: Acute slipped capital femoral epiphysis: Treatment alternatives. J Am Acad Orthop Surg 1994;2:96-106.

Question 22

Figures 1 and 2 are the radiograph and MRI scan of a 16-year-old boy who injured his right knee by a lateral side impact while playing football. The MRI indicates what structure was most likely injured?

Explanation

This is a rupture of the anterolateral ligament complex and a portion of the IT band. This injury is highly correlated with a complete ACL injury. In the MRI, the curvilinear or elliptic bone fragment (Segond fracture) projected parallel to the lateral aspect of the tibial plateau, the lateral capsular sign, is seen. The lateral capsular sign is also associated with ACL tears. Thus, this is an MRI showing a complete ACL tear.

Question 23

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

Explanation

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

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

Question 24

A 35-year-old man is seen for evaluation of his left ankle following multiple previous ankle sprains and frequent episodes of the ankle giving way. Examination reveals marked laxity about the lateral ankle with associated tenderness along the peroneal tendons. Physical therapy, anti-inflammatory drugs, and supportive bracing have failed to provide relief. An MRI scan shows peroneal tenosynovitis and a possible tear. He elects to undergo a peroneal tendon repair and lateral ligament reconstruction. Which of the following best describes the structure labeled “A” in Figure 45?

Explanation

DISCUSSION: The structure labeled “A” is a peroneus quartus, a supernumary muscle arising most commonly from the peroneus brevis. The presence of peroneus quartus is not uncommon, with an incidence of up to 21%, and is associated with lateral ankle pain and peroneal tendon symptoms, theoretically as a result of mass effect within the peroneal tendon sheath.
REFERENCES: Zammit J, Singh D: The peroneus quartus muscle: Anatomy and clinical relevance. J Bone Joint Surg Br 2003;85:1134-1137.
Sobel M, Levy ME, Bohne WH: Congenital variations of the peroneus quartus muscle: An anatomic study. Foot Ankle 1990;11:81-89.

Question 25

A 19-year-old man has had back pain with activity, especially running in soccer and baseball, for the past 4 months. He denies any history of trauma. Examination reveals no motor weakness or sensory changes in the lower extremities. Range of motion shows increased pain with extension and mild limitation with flexion. A sitting straight leg raising test is limited at approximately 60 degrees bilaterally by back and buttocks pain. Plain radiographs are normal. MRI scans are shown in Figures 13a through 13e. What is the most likely diagnosis?

Explanation

DISCUSSION: The patient has an isthmic spondylolysis. The plain radiographs are normal, but the MRI scans show increased marrow edema and signal at the L5 pars interarticularis. Findings of bilateral hamstring tightness and increased pain with extension over flexion suggests spondylolysis. The MRI scans do not show any signs of the other conditions.
REFERENCES: Wiltse LL, Rothman SL: Spondylolisthesis: Classification, diagnosis and natural history. Sem Spine Surg 1993;5:264-280.
Richards BS (ed): Orthopaedic Knowledge Update: Pediatrics. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1996, pp 129-137.

Question 26

A 32-year-old man who works as a laborer has had left trapezius wasting and lateral scapular winging after injuring his shoulder when a cargo box fell onto his neck 8 months ago. He now reports posterior shoulder pain and fatigue, and he has difficulty shrugging his shoulder. Examination reveals marked scapular winging, impingement signs, and an asymmetrical appearance when the patient attempts a shoulder shrug. Primary scapular-trapezius winging is the result of damage to the

Explanation

DISCUSSION: The patient has primary scapular-trapezius winging. This condition can be caused by blunt trauma to the relatively superficial spinal accessory nerve that is located in the floor of the posterior cervical triangle in the subcutaneous tissue. Other causes of injury include penetrating trauma, traction, or surgical injury. With trapezius winging, the shoulder appears depressed and laterally translated because of an unopposed serratus anterior. This contrasts with primary serratus anterior winging, which is caused by injury to the long thoracic nerve. In this condition, the scapula assumes a position of superior elevation and medial translation, and the inferior angle is rotated medially. The thoracodorsal nerve supplies the latissimus dorsi and is not involved in primary scapular winging.
REFERENCES: Kuhn JE, Plancher KD, Hawkins RJ: Scapular winging. J Am Acad Orthop Surg 1995;3:319-325.
Wright TA: Accessory spinal nerve injury. Clin Orthop 1975;108:15-18.

Question 27

A 35-year-old man reports the development of a painful 2-cm nodule on his dorsal wrist over the past 3 years. A surgeon excised the lesion with a presumptive diagnosis of a ganglion cyst. Histology sections from the excision are shown in Figures 11a and 11b. What is the most likely diagnosis?

Explanation

DISCUSSION: The histologic appearance of the soft-tissue lesion reveals compact nests of cells with a clear cytoplasm surrounded by a delicate border of fibrocollagenous tissue. There can be scattered multinucleated giant cells. This is consistent with a clear cell sarcoma, also called malignant melanoma of soft parts. This tumor is usually positive for S-100 and HMB45 (a melanoma-associated antigen). These tumors are frequently found around the foot and ankle. Similar to epithelioid sarcoma, it is usually intimately bound to tendons or tendon sheaths. Often the tumors are present for many years. The classic histologic appearance of this lesion differentiates it from the other choices.
REFERENCES: Enzinger FM, Weiss SW: Soft Tissue Tumors, ed 3. St Louis, MO, Mosby, 1995, p 913.
Lucas DR, Nascimento AG, Sim FH: Clear cell sarcoma of soft tissues: Mayo Clinic experience with 35 cases. Am J Surg Pathol 1992;16:1197-1204.

Question 28

A 46-year-old woman fell from her bicycle and sustained the injury shown in Figure 24. Which of the following ligaments has been disrupted? Review Topic

Explanation

The radiograph shows a type V acromioclavicular joint injury. Type V injuries involve disruption of the acromioclavicular and coracoclavicular ligaments. Type I injuries involve a sprain of the acromioclavicular joint ligaments. Type II injuries involve disruption of the acromioclavicular joint ligaments; the coracoclavicular ligaments are partially injured. Sternoclavicular ligaments stabilize the medial clavicle and the sternum; they are not damaged with acromioclavicular joint dislocations.

Question 29

A 46-year-old male construction worker has right hip pain that has failed to respond to nonsurgical management. His body mass index (BMI) is 32, he is 6’2” tall, and he has no other medical comorbidities. AP and lateral radiographs of the right hip are shown in Figures 23a and 23b. The patient inquires about his suitability for metal-on-metal hip resurfacing. The patient should be educated that he is at higher risk for failure secondary to which of the following?

Explanation

DISCUSSION: This young patient has osteonecrosis of the femoral head with a large area of collapse.
The results of hip resurfacing arthroplasty have been reported to be best in young, male patients who are younger than 55 years of age with a diagnosis of osteoarthritis. Although some authors advocate metal- on-metal hip resurfacing as an option for patients with osteonecrosis of the femoral head, in this particular patient, given the size of the necrotic segment, he would be at higher risk for failure and a conventional total hip arthroplasty would be a more conservative option. As the acetabulum is resurfaced in metal- on-metal hip resurfacing, the secondary changes of the acetabulum are not an issue and his BMI is in an acceptable range for the procedure.
REFERENCES: Mont MA, Ragland PS, Etienne G, et al: Hip resurfacing arthroplasty. J Am Acad Orthop Surg 2006;14:454-463.
Revell MP, McBryde CW, Bhatnagar S, et al: Metal-on-metal hip resurfacing in osteonecrosis of the femoral head. J Bone Joint Surg Am 2006;88:98-103.
Buergi ML, Walter WL: Hip resurfacing arthroplasty: The Australian experience. J Arthroplasty 2007;22:61-65. Question 24
A 31-year-old woman had disabling right knee pain. An arthroscopic assessment reveals chondromalacia of both the lateral femoral condyle and tibial plateau. The standing femorotibial axis measures 10 degrees of valgus. The
optimum treatment of this condition should include
distal femoral varus osteotomy.
osteoarticular transplant to the lateral femoral condyle.
unicondylar arthroplasty.
high tibial osteotomy.
Fulkerson tibial tubercle transfer. PREFERRED RESPONSE: 1
DISCUSSION: The long-term outcome of a distal femoral varus osteotomy has been quite favorable and should remain the primary choice for this young active woman. Sharma and associates have shown that a 5-degree valgus malalignment has a five-fold chance of progressing at least one grade within 18 months, making a corrective osteotomy the most important surgical maneuver.
REFERENCES: Sharma L, Song J, Felson DT, et al: The role of knee alignment in disease progression and function decline in knee osteoarthritis. JAMA 2001 ;286:188-195.
Murray PB, Rand JA: Symptomatic valgus knee: The surgical options. J Am Acad Orthop Surg 1993; 1:19.

Figure 25a Figure 25b Figure 25c

Question 30

Which of the following imaging modalities is most accurate in locating a toothpick in the plantar arch of the foot?

Explanation

DISCUSSION: Ultrasound is best at imaging abrupt changes in the density of adjacent tissue and therefore is best at imaging wood in the soft tissues of the foot.
REFERENCES: Mizel MS, Steinmetz ND, Trepman E: Detection of wooden foreign bodies in muscle tissue: Experimental comparison of computed tomography, magnetic resonance imaging, and ultrasonography. Foot Ankle Int 1994;15:437-443.
Jacobson JA, Powell A, Craig JG, et al: Wooden foreign bodies in soft tissue: Detection at US. Radiology 1998;206:45-48.

Question 31

When performing a bunionectomy with a release of the lateral soft-tissue structures, the surgeon is cautioned against releasing the conjoined tendon that inserts along the lateral base of the proximal phalanx of the great toe. This conjoined tendon is made up of what two muscles?

Explanation

DISCUSSION: Owens and Thordardson cautioned surgeons not to release the conjoined tendon from the base of the proximal phalanx of the great toe because of an increased risk of iatrogenic hallux varus. Release of the transverse and oblique heads of the adductor hallucis is largely accomplished by releasing the soft tissue adjacent to the lateral sesamoid, without releasing tissue from the base of the proximal phalanx. The conjoined tendon is made up of the flexor hallucis brevis and the adductor hallucis.
REFERENCES: Owens S, Thordardson DB: The adductor hallucis revisited. Foot Ankle Int 2001;22:186-191.
Sarrafian SK: Anatomy of the Foot and Ankle. Philadelphia, PA, JB Lippincott, 1983, chapter 5.

Question 32

What is the primary concern for arthrodesis of a failed infected total knee arthroplasty using internal fixation?

Explanation

DISCUSSION: Arthrodesis of the failed infected total knee arthroplasty may be accomplished by external fixation, intramedullary rod fixation, and dual plates and screws. External fixation runs the risk of pin tract infection, although after its removal, there are no metal surfaces left in place. Intramedullary rods have been used successfully in the treatment of infected total knees, although they also leave metal within the region of the infection. The dual plate technique of knee fusion is useful in patients with rheumatoid arthritis who require fusion in the absence of infection because it provides good initial stability and avoids the use of external pins. However, in the face of infection, the large surface area of the screws and plates may serve as a site for bacteria to hide within a glycocalyx and make eradication of the infection almost impossible.
REFERENCE: Windsor RE: Knee arthrodesis, in Insall JN, Windsor R, Kelly M, et al (eds): Surgery of the Knee. New York, NY, Churchill Livingstone, 1993, pp 1103-1116.

Question 33

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

Explanation

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

Question 34

Which of the following anatomic changes is observed as part of the normal aging process of the adult spine?

Explanation

DISCUSSION: The primary change that takes place in the aging spine is degeneration of the lumbar disks and loss of the overall lumbar lordosis. This also may be associated with osteopenic-related compression fractures. With these changes, the sagittal vertical line moves anteriorly relative to the sacrum; cervical scoliosis is uncommon and not part of the normal aging process. Overall kyphosis in the thoracic spine gradually increases, but the coronal balance remains essentially the same unless scoliosis develops.
REFERENCES: Gelb DE, Lenke LG, Bridwell KH, et al: An analysis of sagittal spinal alignment in 100 asymptomatic middle and older aged volunteers. Spine 1995;20:1351-1358.
Vedantam R, Lenke LG, Keeney JA, et al: Comparison of standing sagittal spinal alignment in asymptomatic adolescents and adults. Spine 1998;23:211-215.

Question 35

Which of the following is a recognized consequence of hip fusion?

Explanation

DISCUSSION: Low back pain is an expected long-term complication of fusion; ipsilateral knee laxity is frequently encountered, as is degeneration of the contralateral hip. Hip fusion is equally valuable for both men and women, with both genders reporting satisfactory sexual function. Female patients often deliver by elective Cesarean section, although vaginal deliveries are reported.
REFERENCES: Liechti R (ed): Hip Arthrodesis and Associated Problems. Berlin, Germany, Springer-Verlag, 1978, pp 109-117.
Sponseller PD, McBeath AA, Perpich M: Hip arthrodesis in young patients: A long-term follow-up study. J Bone Joint Surg Am 1984;66:853-859.

Question 36

The initiating cellular event in development of posttraumatic osteoarthritis is attributed to which of the following?

Explanation

A relatively large percentage of patients sustaining intra-articular fractures develop posttraumatic arthritis despite surgical restoration of joint incongruity and alignment. Fracture-related chondrocyte death (apoptosis) concentrated along matrix cracks in the superficial layer of cartilage has been linked to the pathogenesis of posttraumatic osteoarthritis. Apoptosis is accentuated by a series of aspartate-specific cysteine proteases. Inhibition of this cascade is a target of emerging pharmacological treatment options.

Question 37

Which of the following nerves innervates the muscle that originates from the middle third of the dorsal surface of the lateral border of the scapula, as shown in Figure 7?

Explanation

DISCUSSION: Teres minor originates from the middle third of the dorsal surface of the lateral border of the scapula. It is supplied by the axillary nerve (C5).
REFERENCES: Williams PL, Warwick R, Dyson M, Bannister LH: Myology, in Gray’s Anatomy, ed 37. Edinburgh, Scotland, Churchill Livingstone, 1989, pp 611-615.
Last RJ: Anatomy: Regional and Applied, ed 6. London, England, Churchill Livingstone, 1978, pp 68-72.

Question 38

Among patients with adolescent idiopathic scoliosis, a thoracolumbosacral orthosis is most effective for which type of curve?

Explanation

DISCUSSION
A thoracolumbosacral orthosis is most effective for bracing of curves when the apex is at T7 or below. Bracing is used for patients who are skeletally immature (Risser stage 0, 1, or 2), and it is recommended that the brace be worn 16 to 23 hours per day and continued until skeletal maturity or until the curve progresses to beyond 45 degrees, at which point bracing is no longer considered effective.
RECOMMENDED READINGS
Luhmann SJ, Skaggs DL: Pediatric spine conditions, in Lieberman JR (ed): AAOS Comprehensive Orthopaedic Review. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2009, pp 245-265.
Shaughnessy WJ. Advances in scoliosis brace treatment for adolescent idiopathic scoliosis. Orthop Clin North Am. 2007 Oct;38(4):469-75, v. Review. PubMed PMID: 17945126. View Abstract at PubMed

Question 39

What is a known risk factor for lateral distal femoral locking plate failure when used for the fixation of comminuted extra-articular fractures?

Explanation

From the following options, a short working length of the construct is a known risk factor for femoral plate failure.
Implant failure is common in distal femur fractures stabilized with plate fixation. Contributors to failure include a short working length of the construct, plate-screw density more than 0.5 and short plate lengths. This will lead to failure as it causes increased strain on the plate over a short segment, and
does not allow enough motion at the fracture site to form bone for healing by secondary intention.
Ricci et al. reviewed 355 cases of distal femur plate fixation. 64 patients (19%) required reoperation to promote union, including 30 that had a planned staged bone grafting. Risk factors for proximal implant failure included open fracture, smoking, increased body mass index, and shorter plate length.
Kregor et al. reviewed 119 patients with distal femoral plate fixation. They found that 93% fractures healed without acute bone grafting. Complications included 5 losses of proximal fixation, 2 nonunions, and 3 acute infections.
Illustration A is an AP of the distal femur demonstrating a comminuted distal femur fracture which has failed fixation with a laterally based distal femur locking plate. It has undergone varus collapse which is a common mechanism of failure for these injuries. Illustration B is a series of AP radiographs of the distal femur of the same patient that was revised to an intramedullary retrograde nail. Illustration C and D show the concepts of plate length, plate-to-screw density and the working length of the plate.
Incorrect Answers:

OrthoCash 2020

Question 40

What would be the most appropriate surgical indication for transferring fascicles of the ulnar nerve to the motor nerve of the biceps and fascicles of the median nerve to the motor nerve of the brachialis?

Explanation

(SBQ12FA.31) A 30-year-old male patient involved in a hang-gliding accident sustains a knee dislocation with multiligamentous knee injury and transection of his peroneal nerve. He undergoes multiple reconstructive surgeries. Two years later, he continues to have a foot drop and dynamic tendon transfer is recommended. This treatment most commonly involves transferring a tendon from which native insertion point to which new insertion point? Review Topic
Plantar distal phalanges to medial navicular
Medial navicular to dorsal lateral cuneiform
Plantar 1st metatarsal to dorsal lateral cuneiform
5th metatarsal base to dorsal medial cuneiform
Plantar distal phalanx of the hallux to dorsal distal phalanx of hallux
Dynamic tendon transfer to restore active dorsiflexion of the foot involves transferring the posterior tibial tendon (PTT) insertion on the medial navicular to the dorsal lateral cuneiform.
Common peroneal nerve (CPN) injuries following traumatic knee dislocation are common, with an incidence of 25-40%. CPN palsy is characterized by foot drop due to loss of ankle dorsiflexors with a steppage gait and eventual development of a supinated equinovarus foot secondary to the unopposed pull of the PTT. Nonsurgical management involves use of an ankle-foot orthosis and physical therapy. Surgical
options include acute primary repair, nerve grafting with either autologous sural nerve or nerve conduits and dynamic tendon transfer. The PTT is harvested from its insertion at the navicular, passed through the interosseous membrane (IOM) and anchored to the lateral cuneiform (see Illustration A). The classic bridle procedure involves concomitant anastamosis of the PTT to the tibialis anterior (TA) and peroneus longus (PL) tendons.
Garozzo et al reported a case series of 62 patients with post-traumatic CPN palsy who underwent a one-stage procedure consisting of nerve repair and PTT transfer. Nerve repair combined with PTT transfer improved postoperative outcomes compared to nerve repair alone. At 2-year follow up, neural regeneration was demonstrated in 90% of patients. The authors hypothesized that poor outcomes following nerve repair alone are due to force imbalance between the functioning flexors and paralyzed extensors, which is somewhat equalized by performing a PTT transfer at time of repair.
Niall et al reviewed 55 patients with traumatic knee dislocation and reported a 41% incidence of CPN injury, exclusively associated with dislocations involving disruption of the posterior cruciate ligament (PCL) and posterolateral corner (PLC). Complete neurologic recovery was found in only 21% of patients. The best prognosis was found with lesions in continuity, less than 7cm of nerve involvement, and short conduction block and muscle activity on nerve conduction and EMG studies.
Vigasio et al described a dynamic tendon transfer technique for traumatic complete CPN injury, involving transfer of the PTT to the TA rerouted to a new origin at the lateral cuneiform to restore ankle dorsiflexion and flexor digitorum longus (FDL) to the extensor digitorum longus (EDL) and extensor hallucis longus (EHL) to restore digit dorsiflexion. Rerouting the TA towards the transferred PTT ensures the PTT harvest length is sufficient. This avoids excessive tensioning of the PTT, which may limit tendon excursion and result in a static tenodesis rather than dynamic function, as well as the need for PTT lengthening which may decrease strength of the transfer
Illustration A is a series of intraoperative photographs demonstrating PTT transfer from Garg et al. An incision is made distal to the medial malleolus and the PTT is harvested subperiosteally (A). The PTT is delivered through a second incision ~15cm proximal to the medial malleolus (B-C). The PTT is then passed through the interosseous membrane and out a third incision over the anterior fibula (D). Lastly, the PTT is passed through a fourth incision over the dorsal midfoot and anchored to the lateral cuneiform (E).
Incorrect Responses:
nerve and therefore would not be functional. Answer 5: Transferring the flexor hallucis longus (FHL; insertion = plantar distal phalanx of the hallux) to the insertion of the EHL (dorsal distal phalanx of hallux) is recommended for correction of claw toe deformity and would not help restore foot dorsiflexion in this patient.

Question 41

Figure 131 is the abdominal radiograph of a 70-year-old man who experiences nausea and abdominal tightness 48 hours after undergoing left total knee arthroplasty. An examination reveals severe abdominal distension and markedly decreased bowel sounds. Insertion of a nasogastric tube does not relieve abdominal tightness. What is the best next step?

Explanation

DISCUSSION
The abdominal radiograph reveals an acute colonic pseudo-obstruction. It is associated with parenteral narcotic use and hypokalemia. Initial treatment is insertion of a nasograstric tube, discontinuation of parenteral narcotics, and correction of electrolyte imbalances. If a pseudo-obstruction is not relieved, colonoscopy should be performed.

Question 42

A 22-year-old man reports anterior knee pain, swelling, and is unable to perform a straight leg raise after undergoing endoscopic anterior cruciate ligament (ACL) reconstruction with a bone-patellar tendon-bone autograft 1 week ago. He is afebrile. Examination reveals a clean incision, moderate effusion, a weak isometric quadriceps contraction, active knee range of motion of 5 degrees to 45 degrees, and the patella is ballottable. Knee radiographs show postoperative changes with good femoral and tibial tunnel placements, and normal patellar height. What is the next most appropriate step in management?

Explanation

DISCUSSION: Knee pain and swelling in the first week after ACL reconstruction is usually related to a postoperative hemarthrosis. A large hemarthrosis creates capsular distension, which inhibits active quadriceps contraction by a neurologic reflex, the H. reflex. Kennedy and associates reported that an experimentally induced knee effusion at 60 mL was found to result in profound inhibition of reflexly evoked quadriceps contraction. Removal of the hemarthrosis by aspiration will improve strength and often instantaneously restore the ability to contract the quadriceps muscle. A large effusion will also limit knee flexion. EMG and NCVS are not necessary unless there is a high index of suspicion of a femoral neuropathy. Diagnostic ultrasonography is not necessary in this patient but can be useful in the assessment of patellar tendon integrity. MRI is not indicated and would most likely be limited by artifact and postoperative changes. Continuous passive motion is not indicated and would most likely worsen the patient’s symptoms.
REFERENCES: Kennedy JC, Alexander IJ, Hayes KC: Nerve supply of the human knee and its functional importance. Am J Sports Med 1982;10:329-335.
Fahrer H, Rentsch HU, Gerber NJ, et al: Knee effusion and reflex inhibition of the quadriceps: A bar to effective retraining. J Bone Joint Surg Br 1988;70:635-638.

Question 43

A 43-year-old former professional hockey player reports severe pain in his chest after being checked from the side in a pick-up hockey game. An MRI scan and plain radiographs are shown in Figures 25a through 25c. What is the most likely diagnosis?

Explanation

DISCUSSION: Anterior dislocation is the most common type of sternoclavicular dislocation. The medial end of the clavicle is displaced anterior or anterosuperior to the anterior margin of the sternum. In a study by Omer, 31% of athletic injuries have been known to cause a dislocation of the sternoclavicular joint. The serendipity view can show this dislocation, as will CT of the chest. This view requires the x-ray beam to be aimed at the manubrium with 40 degrees of cephalic tilt. An anterior sternoclavicular joint dislocation will appear superiorly displaced, while a posterior sternoclavicular joint dislocation is inferiorly displaced on the serendipity view.
REFERENCES: Rockwood CA Jr, Matsen FA III (eds): The Shoulder. Philadelphia, PA, WB Saunders, 1998, vol 1, pp 566-572.
Omer GE Jr: Osteotomy of the clavicle in surgical reduction of anterior sternoclavicular dislocation. J Trauma 1967;7:584-590.

Question 44

A researcher decides she wants to look at the current total number of patients who have methicillin-resistant Staphylococcus aureus (MRSA) infections in a hospital on 1 particular day. What is the researcher measuring?

Explanation

The prevalence of a disease is a measure of the number of cases of a disease at or during a specific time point or time period. In this case, the researcher wants to know the prevalence of disease on a given day. Incidence measures new cases of a disease or event per unit of time. Correlation coefficient is a measure of how 2 things correlate with one another, while relative risk is a statistical outcome that is often used in case-control or cohort studies to provide a measure of the risk of a particular disease occurring when a certain exposure has already occurred.

Question 45

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 46

A 3-year-old girl has had pain and swelling in her left thigh for the past 3 weeks. Her mother states she has had a temperature as high as 100.4 degrees F (38 degrees C) and a weight loss of 5 pounds. A CBC shows a WBC count of 11,000/mm3, an erythrocyte sedimentation rate of 13 mm/h, and a C-reactive protein of 0.3. A radiograph is shown in Figure 2. What is the next step in management?

Explanation

DISCUSSION: The history and laboratory studies indicate that this is not an infection. A lesion in this location and in this age group is likely a Ewing’s sarcoma. The presentation is usually a painful mass. About 20% of patients have a fever. The radiograph shows a typical mottled, permeative lesion with periosteal reaction. An MRI scan should be obtained to further evaluate the soft-tissue mass. Staging of the lesion should take place before biopsy, which should be done by the surgeon who would be performing the next stage of surgical treatment, ideally an orthopaedic oncologist.
REFERENCES: Gibbs CP Jr, Weber K, Scarborough MT: Malignant bone tumors. Instr Course Lect 2002;51:413-428.
Meyer JS, Nadel HR, Marina N, et al: Imaging guidelines for children with Ewing sarcoma and osteosarcoma: A report from the Children’s Oncology Group Bone Tumor Committee. Pediatr Blood Cancer 2008;51:163-170.
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AL-Madena Copy

Question 47

Figure 1 shows the radiograph obtained from a 54-year-old woman with rheumatoid arthritis who has thumb pain and dysfunction. Nonsurgical treatment, including splinting, oral NSAIDs, activity modification, and steroid injections, has failed. What is the most appropriate surgical intervention?

Explanation

EXPLANATION:
Various options exist to treat thumb CMC arthritis: trapezial resection alone, trapezial resection with ligament suspensionplasty or tendon interposition, trapezial resection with both ligament suspensionplasty and tendon interposition, CMC fusion, and CMC replacement. MCP hyperextension can develop in long-standing CMC arthritis, contributing to CMC instability as well as thumb pain and weakness. In patients with concomitant MCP hyperextension that exceeds 30°,
correction of the deformity of the MCP joint must also be addressed and can be done with MCP capsulodesis, extensor pollicis brevis tendon transfer, or MCP fusion. Fusion of both the thumb CMC and MP joints is not recommended as this would result in marked stiffness and dysfunction.

Question 48

Figures 35a and 35b show the radiographs of a 20-year-old man who is unable to rotate his dominant forearm. Examination reveals that the arm is fixed in supination. To regain motion, management should consist of

Explanation

DISCUSSION: The patient has a proximal synostosis; therefore, resection of the synostosis is considered the best option to regain motion. While forearm osteotomy can place the hand in a more functional position, rotation will not be restored. Proximal radial excision can provide forearm rotation; however, this procedure is reserved for patients who have a proximal radioulnar synostosis that is too extensive to allow a safe resection, involves the articular surface, and is associated with an anatomic deformity. Motion will not be restored with dynamic splinting.
REFERENCES: Kamineni S, Maritz NG, Morrey BF: Proximal radial resection for posttraumatic radioulnar synostosis: A new technique to improve forearm rotation. J Bone Joint Surg Am 2002;84:745-751.
Jupiter JB, Ring D: Operative treatment of post-traumatic proximal radioulnar synostosis.

J Bone Joint Surg Am 1998;80:248-257.

Question 49

Figures 1 and 2 display the radiographs obtained from a woman who had volar plating of the distal radius 8 months earlier. Two days ago, she noticed she could not actively extend her thumb. What is the most appropriate treatment that would restore active thumb extension?

Explanation

EXPLANATION:
Although the fracture is aligned in anatomic position, prominence of a least one of the distal screws is evident on the lateral radiographic view. The prominent screw is the most likely cause of the EPL tendon rupture. If the patient chooses surgical treatment, the best option would be removal of the offending hardware combined with extensor indicis proprius to EPL tendon transfer. Intercalary grafting would also be an acceptable option. If the tendon transfer were to be performed alone, the prominent screw(s) could rupture the transferred tendon as well. Also, it is rarely possible to repair the EPL tendon primarily in such cases, because this rupture is an attrition type. Casting would obviously not provide any benefit in this situation, and IP arthrodesis would not be the first surgical treatment option. This problem can be avoided by using shorter screws or not placing screws in plate holes that direct screws into the third dorsal extensor compartment. Intraoperative fluoroscopy and special views, such as the carpal shoot-through view, are useful for avoiding this complication.

Question 50

Which of the following factors has the greatest effect on the pull-out strength of a lumbar pedicle screw?

Explanation

DISCUSSION: All of the factors listed contribute to some extent to the pull-out strength of lumbar pedicle screws, but bone mineral density correlates most precisely.
REFERENCES: Wittenberg RH, Shea M, Swartz DE, et al: Importance of bone mineral density in instrumented spine fusions. Spine 1991;16:647-652.
Zindrick MR, Wiltse LL, Widell EH, et al: A biomechanical study of intrapeduncular screw fixation in the lumbosacral spine. Clin Orthop 1986;203:99-112.

Question 51

Sudden cardiac death in the young athlete is most frequently caused by

Explanation

DISCUSSION: Hypertrophic cardiomyopathy is the leading cause of sudden cardiac death in athletes, accounting for 40% of reported cases. Most athletes have no previous symptoms, and sudden death may be the first clinical manifestation. The prevalence of hypertrophic cardiomyopathy in the general population is 1 in 500, with a mortality rate of 2% to 4% in young adults. Athletes with active myocarditis should not engage in sports for up to 6 months, and although they may be at risk for the development of chronic cardiomyopathy, it is rarely a cause of sudden cardiac death. Mitral valve prolapse with an accompanying systolic murmur is common in the general population, but infrequently a cause of sudden cardiac death. Weakening of the aortic wall associated with Marfan syndrome can result in abrupt rupture of the aorta. This accounts for 3% of sudden cardiac deaths in young athletes. Marfan syndrome usually can be detected on preparticipation screenings by its skeletal and ocular manifestations. Atherosclerotic coronary artery disease is the most common cause of sudden cardiac death in older athletes, accounting for 75% of reported cases. However, it is much less common in the young competitive athlete.
REFERENCES: Burke AP, Farb A, Virmani R, Goodin J, Smialek JE: Sports-related and non-sports-related sudden cardiac death in young adults. Am Heart J 1991;121:568-575.
Maron BJ, Sharani J, Poliac LC, Mathenge R, Roberts WC, Mueller FO: Sudden death in young competitive athletes: Clinical, demographic, and pathological profiles. JAMA

1996;276:199-204.

Question 52

What is the most common cause for poor outcomes in patients who undergo total shoulder arthroplasty? Review Topic

Explanation

In an article in the Journal of Shoulder and Elbow, 431 total shoulder arthroplasties were performed with a cemented all-polyethylene glenoid component between 1990 and 2000. Follow-up averaged 4.2 years. In total, 53 surgical complications occurred in 53 patients (12%). Of these, 32 were major complications (7.4%), with 17 of these requiring reoperation. Index complications in order of frequency included rotator cuff tearing, postoperative glenohumeral instability, and periprosthetic humeral fracture. Notably, glenoid and humeral component loosening requiring reoperation occurred in only one shoulder. Data from the contemporary patient group suggest that there are fewer complications of shoulder arthroplasty and less need for reoperation. Especially striking is the near absence of component revision because of loosening or other mechanical factors. Complications involving the brachial plexus have been reported following total shoulder arthroplasty but are not as common of a cause for failure.

Question 53

The insurance carrier of a patient who underwent total knee arthroplasty 4 days ago is now demanding that the patient be discharged from the hospital. However, examination reveals that the patient has a range of motion of only 10° to 55°, and the patient is concerned whether she will ever move her knee normally. The insurance company representative should be advised that

Explanation

DISCUSSION: Examination findings that show flexion of only 55° at discharge should alert the surgeon that the patient will require close scrutiny and follow-up. Mauerhan and associates examined the records of 745 patients who had a primary total knee arthroplasty from 1993 to 1996. At their institution, development and implementation of clinical pathways resulted in a significant decrease in the average length of stay, beginning in 1993 with 6.4 days +/- 1.8 days and progressively decreasing to 4.4 days +/- 1.0 days in 1996. The rate of manipulation (patients manipulated at 6 weeks/total number of patients receiving total knee arthroplasty) was 6.0% in 1993, 11.3% in 1994, 13.5% in 1995, and 12.0% in 1996. In the period of 1993 to 1996, patients requiring manipulation consistently had a lower range of motion of 69.0° +/- 10° at the time of discharge compared with patients not requiring manipulation who had a range of motion of 80.7° +/- 10.6°. In this era of outpatient services, however, another solution would be to arrange for outpatient physical therapy on a more frequent basis and to see the patient more frequently in the office until an acceptable range of motion is established.
REFERENCE: Mauerhan DR, Mokris JG, Ly A, Kiebzak GM: Relationship between length of stay and manipulation rate after total knee arthroplasty. J Arthroplasty 1998;13:896-900.

Question 54

A 63-year-woman has an elbow flexion contracture. History reveals that she underwent three previous surgeries to remove a malignant fibrous histiocytoma of the forearm. An MRI scan reveals a locally recurrent tumor at the site of the previous surgery. Which of the following is considered the most predictive factor for local recurrence?

Explanation

DISCUSSION: The greatest risk factor for local recurrence is an inadequate surgical margin. The tumor grade, histologic subtype, and size are predictive of systemic relapse. Sarcomas that arise in some anatomic sites, such as the forearm or retroperitoneum, may be more difficult to completely resect compared with other sites. The optimum margin is generally considered to be a cuff of normal tissue beyond the tumor.
REFERENCES: Bell RS, O’Sullivan B, Liu FF, et al: The surgical margin in soft-tissue sarcoma. J Bone Joint Surg Am 1989;71:370-375.
Sadoski C, Suit HD, Rosenberg A, Mankin H, Efird J: Preoperative radiation, surgical margins, and local control of extremity sarcomas of soft tissues. J Surg Oncol 1993;52:223-230.
Wilson AN, Davis A, Bell RS, et al: Local control of soft tissue sarcoma of the extremity: The experience of a multidisciplinary sarcoma group with definitive surgery and radiotherapy. Eur J Cancer 1994;30:746-751.

Question 55

What is the most appropriate surgical treatment for a stage III symptomatic scapholunate advanced collapsed (SLAC) wrist?

Explanation

DISCUSSION: SLAC is the end result of chronic scapholunate instability. The arthritis follows a predictable pattern. Stage I disease involves cartilage loss between the waist of the scaphoid and the radial styloid. In stage II, the arthritis progresses to include the proximal pole of the scaphoid and the scaphoid fossa of the radius. Finally, stage III goes on to include arthritis of the capitolunate joint. The only treatment option that addresses all of the sites of arthritis is the scaphoid excision and four corner fusion.
REFERENCES: Ashmead DT IV, Watson HK, Damon C, et al: Scapholunate advanced collapse wrist salvage. J Hand Surg Am 1994;19:741-750.
Sauerbier M, Trankle M, Linsner G, et al: Midcarpal arthrodesis with complete scaphoid excision and interposition bone graft in the treatment of advanced carpal collapse (SNAC/SLAC wrist): Operative technique and outcome assessment. J Hand Surg Br 2000;25:341-345.

Question 56

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

Explanation

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

Question 57

Figure 1 is the clinical photograph of a 64-year-old man who crashed while riding his motorcycle. An examination reveals his long-finger metacarpophalangeal (MP) joint is stuck in extension. He cannot passively or actively flex at the MP joint. A hand radiograph is seen in Figure 2. Which interposed structure is preventing reduction?

Explanation

EXPLANATION:
This patient has a dorsally dislocated MP joint. In these cases, the volar plate can be displaced dorsal to the metacarpal head, preventing reduction. Although early publications described a “noose effect” of the lumbrical and flexor tendons, the primary block to reduction is the volar plate. Simple MP dislocations can be reduced closed by flexing the wrist and then gently sliding the base of the proximal phalanx over the end of the metacarpal. Longitudinal traction on the finger will only incarcerate the volar plate further and should be avoided. Patients with complex dislocations that fail closed reduction require open
reduction.

Question 58

Figure 50 shows the radiograph of a 26-year-old man who sustained an isolated open injury to his foot. Examination reveals no gross contamination in the wound. There is a palpable dorsalis pedis pulse and sensation is present on the dorsal and plantar aspects of the foot. Initial treatment should consist of wound debridement, antibiotics, and

Explanation

DISCUSSION: The radiograph shows a complete extrusion of the talus. Reimplantation of the talus after wound debridement has been reported to be safe and successful, and provides for flexibility with any future reconstructive procedures.
REFERENCES: Smith CS, Nork SE, Sangeorzan BJ: The extruded talus: Results of reimplantation. J Bone Joint Surg Am 2006;88:2418-2424.
Brewster NT, Maffulli N: Reimplantation of the totally extruded talus. J Orthop Trauma 1997;11:42-45.

Question 59

A 27-year-old man has recurrent right shoulder instability. He first dislocated his shoulder in college while playing rugby and was treated nonsurgically. Since then, he has sustained nearly 1 dozen dislocations and says that his shoulder always feels “loose.” The shoulder recently dislocated in his sleep and while he was putting on clothes. Which factor is a contraindication to an arthroscopic soft-tissue repair?

Explanation

CLINICAL SITUATION FOR QUESTIONS 90 THROUGH 92
Figure 90 is the radiograph of a 14-year-old pitcher who plays in a year-round baseball program and has vague pain in his dominant shoulder. The pain occurs with throwing, and it has been worsening for 2 months. Pain typically occurs during the late cocking phase of throwing. He has no tenderness of the rotator cuff and 5/5 rotator cuff strength. His arc of motion is symmetric between his dominant and nondominant arms. The sulcus sign is negative.

Question 60

A 22-year-old male soccer player reports left hip and groin pain. He states that symptoms began before a preseason tournament but have worsened steadily for the past 2 weeks. He denies any recent fever or sickness and is otherwise healthy. Examination reveals tenderness over the symphysis pubis and pain with resisted rectus abdominus testing. Radiographs are negative. What is the next step in the proper management of this patient? Review Topic

Explanation

Appropriate management of osteitis pubis includes rest, nonsteroidal anti-inflammatory drugs, directed rehabilitation, and gradual return to sports. Lack of fever or chills excludes osteomyelitis as a source of pain. Examination with tenderness over the symphysis pubis and pain with resisted rectus abdominus testing is consistent with osteitis pubis as opposed to a sports hernia, where a patient would be tender in the abdomen, not the pubis. There is no symphyseal instability that would require symphyseal plating.

Question 61

During an anterior approach to the shoulder, excessive traction on the conjoined tendon is most likely to result in loss of

Explanation

DISCUSSION: The musculocutaneous nerve travels through the conjoined tendon approximately 8 cm distal to the tip of the acromion. The musculocutaneous nerve innervates the biceps muscle and the bracialis muscle, both of which are responsible for elbow flexion. Shoulder flexion is facilitated by the anterior fibers of the deltoid muscle (axillary nerve) and the supraspinatus muscle (suprascapular nerve). The subscapular muscle facilitates internal rotation of the shoulder (upper and lower subscapularis nerve). Shoulder abduction is performed by the deltoid muscle (axillary nerve), and forearm pronation is facilitated by the pronator teres (median nerve).
REFERENCES: Hollinshead WH: Anatomy for Surgeons: The Back and Limbs, ed 3. Philadelphia, PA, Harper and Row, 1982, pp 391-393.
Hoppenfeld S, deBoer P: Surgical Exposures in Orthopaedics: The Anatomic Approach, ed 2. Philadelphia, PA, Lippincott-Raven, 1992, pp 2-49.

Question 62

What is the structure indicated by the letter “A” in Figure A? Review Topic

Explanation

The ligaments shown are the components of the lateral collateral ligament complex, and the structure indicated by the letter “A” is the radial collateral ligament. The lateral ulnar collateral ligament is the structure indicated by the letter “C” and the annular ligament is indicated by the letter “B.” The transverse ligament is a component of the medial collateral ligament complex.

Question 63

A 67-year-old man with right shoulder osteoarthritis (OA) remains symptomatic despite a course of nonsurgical treatment. A CT scan of the shoulder shows eccentric posterior glenoid wear with 10° of retroversion. What is the appropriate management of this glenoid bone loss during surgery for an anatomic total shoulder arthroplasty?

Explanation

Total shoulder arthroplasty (TSA) is superior to hemiarthroplasty for primary OA. The most common complication of TSA is glenoid loosening and malposition, which are common causes of glenoid failure. Glenoid malposition decreases the glenohumeral contact area and subsequently increases contact pressures. Altering the stem version to accommodate glenoid retroversion does not appropriately address soft-tissue balancing. A retroversion of <12° to 15° can be corrected with eccentric reaming without excessively compromising glenoid bone stock and risking glenoid vault penetration by the glenoid component. Posterior
glenoid bone grafting may be considered for glenoid retroversion >15°.

Question 64

A 45-year-old woman has had radiating pain in the medial ankle for the past 3 months. Examination reveals a small mass in the retromedial ankle region and a positive Tinel’s sign. An intraoperative photograph and a hematoxylin/eosin biopsy specimen are shown in Figures 24a and 24b. Treatment should consist of

Explanation

DISCUSSION: Neurilemoma is a benign tumor of nerve sheath origin, and peak incidence is in the third through sixth decades. The tumor is well encapsulated on the surface of a peripheral nerve. MRI findings may be significant for a “string sign.” A positive Tinel’s sign in the distribution of the nerve affected may be present. Grossly, the lesion is well encapsulated in a nerve sheath. Microscopically, there are structures referred to as Antoni A (a pattern of spindle cells arranged in intersecting bundles) and Antoni B (areas with less cellularity with loosely arranged cells). These lesions are benign, and treatment should consist of marginal excision. Nerve function may be preserved by careful dissection, excising the lesion parallel to the nerve fascicles so the lesion may be extruded. Recurrence is rare.
REFERENCES: Walling AK: Soft tissue and bone tumors, in Coughlin MJ, Mann RA (eds): Surgery of the Foot and Ankle, ed 7. St Louis, MO, Mosby, 1999, pp 1007-1032.
Simon M, Springfield D: Surgery for the Bone and Soft-Tissue Tumors. Philadelphia, PA, Lippincott Williams & Wilkins, 1998, pp 530-531.

Question 65

A 40-year-old man who is an avid weight lifter has had chronic pain in the proximal anterior shoulder for the past year. He denies any history of trauma. Examination reveals tenderness at the intertubercular groove, a positive speed test, and a positive Neer impingement sign. Nonsurgical management has failed to provide relief, and he is now considering surgery. Arthroscopic findings in the glenohumeral joint are shown in Figure 31. Based on these findings, treatment should consist of

Explanation

DISCUSSION: The arthroscopic image shows a tear through more than 50% of the biceps tendon; therefore, treatment should consist of tenodesis or tenotomy of the tendon. However, because this patient is relatively young and active, the treatment of choice is tenodesis of the biceps tendon.
REFERENCES: Sethi N, Wright R, Yamaguchi K: Disorders of the long head of the biceps tendon. J Shoulder Elbow Surg 1999;8:644-654.
Eakin CL, Faber KJ, Hawkins RJ, et al: Biceps tendon disorders in athletes. J Am Acad Orthop Surg 1999;7:300-310.
Burkhead WZ, Arcand MA, Zeman C, et al: The biceps tendon, in Rockwood CA, Matsen FA, Wirth MA, et al (eds): The Shoulder, ed 2. Philadelphia, PA, WB Saunders, 1996.

Question 66

Figure 19 shows an arthroscopic view from the anterior lateral portal of the knee looking into the suprapatella pouch. The use of an electrothermal device during this procedure most commonly causes significant postoperative complications by damaging which of the following structures?

Explanation

DISCUSSION: While it is possible to damage any of these structures, unrecognized intraoperative laceration without adequate coagulation of the superior lateral geniculate artery is common. This can result in significant postoperative hemarthrosis and a return to surgery when bleeding cannot be controlled.
REFERENCES: Cash JD, Hughston JC: Treatment of acute patella dislocation. Am J Sports Med 1988;16:244-249.
Henry R, Goletz B, Williamson C: Lateral release in patello-femoral subluxation. Am J Sports Med 1986;14:121.

Question 67

A patient with diabetic peripheral neuropathy undergoes a partial first ray amputation for a chronic ulcer beneath the first metatarsal head. The insertion of the anterior tibialis is preserved. The patient has 10 degrees of passive dorsiflexion at the ankle and no other foot deformities or ulcers. Which of the following is considered appropriate shoe wear for this patient?

Explanation

DISCUSSION: The steel shank is a flat 1-inch steel strip placed between layers of the shoe to extend the foot lever and prevent deformity at the toe break seen following a partial first ray amputation. A rocker sole may be added as well to facilitate transition from foot flat to the toe-off phase of gait. Proper shoe fit is important, but “snug” fitting shoes in a patient with peripheral neuropathy and likely fluctuations in volume from intermittent swelling are to be avoided. A custom shoe is an unnecessary expense. The patient has at least 10 degrees of dorsiflexion at the ankle with an intact anterior tibialis muscle; therefore, catching the sole on carpeting should not be a problem.
REFERENCES: Philbin TM, Leyes M, Sferra JJ, et al: Orthotic and prosthetic devices in partial foot amputations. Foot Ankle Clin 2001;6:215-228.
Pinzur MS, Dart HC: Pedorthic management of the diabetic foot. Foot Ankle Clin 2001;6:205-214.

Question 68

What range of motion parameters are required for a patient with posttraumatic elbow stiffness to accomplish all the normal activities of daily living?

Explanation

DISCUSSION: Activities of daily living such as dressing, eating, and bathing can all be performed with elbow motion through a 100 degrees arc of flexion and extension (30 degrees to 130 degrees) and a 100 degrees arc of forearm rotation (50 degrees pronation, 50 degrees supination). Some patients can accomplish these activities of daily living with 10 degrees less motion at each end point. This is referred to as the functional arc of motion.
REFERENCES: Kasser JR (ed): Orthopaedic Knowledge Update 5. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1996, pp 283-294.
Morrey BF, Askew LJ, Chao EY: A biomechanical study of normal functional elbow motion. J Bone Joint Surg Am 1981;63:872-877.

Question 69

Figure 14 shows an intra-articular gadolinium-enhanced MRI scan of a 52-year-old woman who has stopped playing tennis because of pain in her left shoulder while serving. What is the most likely diagnosis?

Explanation

DISCUSSION: The MRI scan shows increased signal intensity along the deep fibers of the supraspinatus near its insertion. This is typical of tendinosis and a probable partial-thickness rotator cuff tear.
REFERENCES: Herzog RJ: Magnetic resonance imaging of the shoulder. Instr Course Lect 1998;47:3-20.
Iannotti JP, Zlatkin MB, Esterhai JL, et al: Magnetic resonance imaging of the shoulder: Sensitivity, specificity, and predictive value. J Bone Joint Surg Am 1991;73:17-29.

Question 70

Which of the following physical examination findings is most likely present in the condition producing the MRI findings shown in Figure 92? Review Topic

Explanation

The T2-weighted sagittal MRI scan shows the classic "bone bruise" pattern seen with an anterior cruciate ligament (ACL) tear. These lesions are thought to represent subcortical trabecular hemorrhages and are manifested as an increase in signal intensity on T2-weighted images and diminished signal intensity on T1-weighted images. They are classically located in the mid-portion of the lateral femoral condyle and posterior aspect of the lateral tibial plateau. This is due to the fact that an ACL tear typically is the result of a valgus-external rotation of the femur on the fixed tibia. This places most of the weight-bearing stress on the lateral femoral condyle, which rotates laterally and impacts the posterior lip of the lateral tibial plateau. This may result in an impaction fracture if the force is great enough, but more frequently causes merely a microfracture of the involved subcortical trabeculae.

Question 71

Anterior penetration of an iliosacral screw through the sacral ala would most likely lead to weakness of which of the following movements?

Explanation

DISCUSSION: Penetration of an iliosacral screw through the sacral ala would injure the ipsilateral L5 nerve root (great toe dorsiflexion). This can be avoided with proper understanding of the sacral anatomy as well as iliosacral screw starting points. The three required views for placement of this screw are: lateral sacral, pelvic inlet, and pelvic outlet. The referenced study by Ziran et al is an excellent review of fluoroscopic evaluation of screw placement. They reported that the anterior border of the S1 body is best seen with overlap of the S1 and S2 anterior cortex while the superior aspect of the S1 foramen is best seen with overlap of the S2 foramen on the superior pubic ramus.
The referenced study by Routt et al reviewed 177 patients with pelvic ring injuries treated with these screws and found that quality triplanar imaging decreased intraoperative and postoperative complications. They also recommend supplemental fixation of iliosacral screws with posterior plating in noncompliant patients.

Question 72

A 32-year-old amateur bowler has progressive pain in the lateral aspect of the proximal forearm and elbow. Nonsurgical management consisting of a tennis elbow brace, nonsteroidal anti-inflammatory drugs, and activity modification has failed to provide relief. Examination reveals tenderness in the lateral aspect of the proximal forearm and exacerbation of symptoms with resisted finger extension. Radiographs of the elbow reveal no abnormalities. Which of the following studies will aid in diagnosis?

Explanation

DISCUSSION: It is often difficult to accurately discern between lateral epicondylitis and radial tunnel syndrome. Neither MRI nor a bone scan is likely to reveal abnormalities. Electrodiagnostic studies are often inconclusive, and radial tunnel syndrome often presents without motor weakness. The symptoms of radial tunnel syndrome are expected to improve with an injection of lidocaine into the radial tunnel; therefore, this is the test of choice in this clinical scenario. Radiographs of the wrist will not assist in making the diagnosis.
REFERENCES: Eversmann WW Jr: Entrapment and compression neuropathies, in Green DP (ed): Operative Hand Surgery, ed 3. New York, NY, Churchill Livingston, 1993, pp 1341-1385.
Sarhadi NS, Korday SN, Bainbridge LC: Radial tunnel syndrome: Diagnosis and management. J Hand Surg Br 1998;23:617-619.

Question 73

What is the primary mechanism of injury for the fracture shown in Figures 33a and 33b?

Explanation

DISCUSSION: The radiographs show a triplane fracture of the ankle. In adolescence, closure of the distal tibial physis starts peripherally at the anteromedial aspect of the medial malleolus and extends posteriorly and laterally. The anterolateral quadrant of the physis is the last to close, making this region the most susceptible to separation. When the foot is twisted into external rotation, the anterolateral portion of the epiphysis is avulsed by the pull of the anterior tibiofibular ligament. When this fragment alone is avulsed, the result is a juvenile Tillaux fracture. When the fracture extends to involve the remainder of the physis and posterior metaphysis, as in this patient, the result is a triplane fracture.
REFERENCES: Richards BS (ed): Orthopaedic Knowledge Update: Pediatrics. Rosemont, Ill, American Academy of Orthopaedic Surgeons, 1996, pp 267-272.
Dias LS, Giegerich CR: Fractures of the distal tibial epiphysis in adolescence. J Bone Joint Surg Am 1983;65:438-444.
Kling TF Jr: Operative treatment of ankle fractures in children. Orthop Clin North Am 1990;21:381-392.

Question 74

A 56-year-old mechanic has had pain in the hypothenar region of his dominant right hand for the past 6 months. He reports weakness in his grip and pain is worse with activity. Which of the following examination findings is most suggestive of a cervical etiology? Review Topic

Explanation

Hypothenar atrophy is a nonspecific sign that can be seen in ulnar neuropathy, C8 radiculopathy, or even cervical myelopathy; however, the atrophy usually is not unilateral and includes other muscle groups. The Spurling test is an excellent method of eliciting cervical radicular pain but involves hyperextension and ipsilateral rotation of the cervical spine, resulting in nerve root compression by reducing the cross-sectional area of the ipsilateral neuroforamen. Tinel’s sign at the levator scapulae, if present, is indicative of an upper cervical (C3 or C4) radiculopathy. A subluxable ulnar nerve at the cubital tunnel, while often asymptomatic, points toward cubital tunnel syndrome as an etiology for this patient’s pain. The shoulder abduction relief (SAR) sign (relief of upper extremity pain with shoulder abduction) is virtually pathognomic of cervical radiculopathy because this maneuver results in relaxation of a compressed and/or inflamed cervical nerve root. The SAR sign is the converse analog of the straight leg raising sign in the lumbar examination for lumbar radiculopathy, as it relieves tension in the nerve root, thereby relieving symptoms.

Question 75

A 72-year-old man undergoes an uncomplicated cementless total hip arthroplasty for advanced osteoarthritis. At his 6-week postoperative follow-up, he has minimal pain and is progressing well with his mobility. Radiographs show early formation of Brooker grade III heterotopic bone around his hip. What is the best treatment of the heterotopic bone at this time?

Explanation

DISCUSSION: The development of heterotopic bone occurs early after hip arthroplasty. The process begins within days after surgery; therefore, prophylactic treatment must be in the early postoperative period (preoperative radiation given within 24 hours of surgery, or postoperative radiation given within 72 hours of surgery, or nonsteroidal antiinflammatory drugs (NSAIDs) given postoperatively for 7 to 21 days - longer duration has not been shown to be of any additional benefit). At 6 weeks, prophylactic treatment with NSAIDs or radiation is no longer effective. Surgery at 10 weeks would be premature because the patient is currently asymptomatic with regards to the heterotopic bone, and surgery prior to full maturation of the bone may increase the risk for more abundant recurrence of bone.
REFERENCES: Balboni TA, Gobezie R, Mamon HJ: Heterotopic ossification: Pathophysiology, clinical features, and the role of radiotherapy for prophylaxis. Int J Radiat Oncol Biol Phys 2006;65:1289-1299. Fransen M, Neal B: Non-steroidal anti-inflammatory drugs for preventing heterotopic bone formation after hip arthroplasty. Cochrane Database Syst Rev 2004;3:CD001160.
Neal BC, Rodgers A, Clark T, et al: A systematic survey of 13 randomized trials of non-steroidal antiinflammatory

drugs for the prevention of heterotopic bone formation after major hip surgery. Acta Orthop Scand 2000;71:122-128.

Question 76

What zone of the physis is widened in rickets?

Explanation

DISCUSSION: Rickets causes widening of the hypertrophic layer of the physis because of the failure of mineralization and vascular invasion. The other zones of the physis may be altered in other disease conditions but remain relatively unchanged in rickets.
REFERENCES: Hunziker EB, Schenk RK, Cruz-Orive LM: Quantitation of chondrocyte performance in growth-plate cartilage during longitudinal bone growth. J Bone Joint Surg Am 1987;69:162-173.
Iannotti JP: Growth plate physiology and pathology. Orthop Clin North Am 1990;21:1-17.

Question 77

A 67-year-old woman undergoes a revision total shoulder arthroplasty for replacement of a loose glenoid component. Examination in the recovery room reveals absent voluntary deltoid and triceps contraction, weakness of wrist and thumb extension, and absent sensation in the palmar aspect of all fingertips and the radial forearm. The next most appropriate step in management should consist of

Explanation

DISCUSSION: Neurologic injury after shoulder replacement is relatively uncommon, occurring in 4% of shoulders in one large series. The importance of identifying and protecting the musculocutaneous and axillary nerves cannot be overemphasized; it is especially critical during revision arthroplasty when the normal anatomic relationships have been distorted. The long deltopectoral approach leaving the deltoid attached to the clavicle was found to be significant in the development of postoperative neurologic complications. A correlation was found between surgical time and postoperative neurologic complications, with long surgical times being associated with more neurologic complications. The presumed mechanism of injury is traction on the plexus that occurs during the surgery. A neurologic injury after total shoulder arthroplasty usually does not interfere with the long-term outcome of the arthroplasty itself; it is best managed by protective measures with passive range of motion of the involved extremity.
REFERENCES: Wirth MA, Rockwood CA Jr: Complications of shoulder arthroplasty. Clin Orthop 1994;307:47-69.
Lynch NM, Cofield RH, Silbert PL, Hermann RC: Neurologic complications after total shoulder arthroplasty. J Shoulder Elbow Surg 1996;5:53-61.

Question 78

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 79

Which of the following factors increases the risk of sciatic nerve injury in primary total hip arthroplasty (THA)?

Explanation

DISCUSSION: Injury to the sciatic nerve is a relatively rare but serious complication of THA. Dissection of the sciatic nerve is not typically done during primary THA, although the nerve can be identified during the surgical approach. An anterolateral approach to THA would not necessarily be associated with any greater incidence of sciatic nerve injury than other approaches. Screw fixation for the acetabular component is often a matter of surgeon preference. Provided that the anatomic safe zones for screw fixation (posterior inferior and posterior superior) are recognized, injury to the sciatic nerve from acetabular screws can be minimized. Restoration of anatomic length is important in primary THA. Overlengthening can result in sciatic nerve palsy. Developmental dysplasia of the hip can lead to a congenitally shortened extremity with concomitant congenital shortening of the associated neurovascular structures. Overlengthening of the extremity during THA for developmental dysplasia of the hip can lead to sciatic palsy. Osteonecrosis is not an associated risk factor for sciatic nerve palsy.
REFERENCES: DeHart MM, Riley LH Jr: Nerve injuries in total hip arthroplasty. J Am Acad Orthop Surg 1999;7:101-111.
Anas P, Felix B: Evaluation and prevention of postoperative complications, in Neurologic Injury in Revision THA. New York, NY, Springer Verlag, 1999, pp 361-371.

Question 80

A 42-year-old woman reports neck stiffness, upper extremity pain, clumsiness, weakness, and instability of gait. Examination reveals 4+ of 5 strength in the upper extremities and 3+ biceps, brachioradialis, and patellar reflexes with a positive Hoffman sign bilaterally. MRI and CT scans are shown in Figures 10a and 10b. Based on the history and imaging findings, what is the most likely diagnosis? Review Topic

Explanation

The sagittal T2-weighted MRI scan shows moderate-severe multilevel cervical stenosis. The cord compression is noted to be not only at the disk levels but also at the midvertebral body levels, and the posterior longitudinal ligament appears to be thickened. The CT scan confirms that the posterior longitudinal ligament is indeed thickened and ossified, compatible with a diagnosis of ossification of the posterior longitudinal ligament. This diagnosis is most common in individuals of Japanese descent and has a genetic linkage. The anterior osteophytes are smaller than those seen in diffuse idiopathic skeletal hyperostosis and are not syndesmotic. Patients with ankylosing spondylitis typically have non-marginal syndesmophytes. Patients with rheumatoid arthritis may have evidence of instability at C1-C2 on flexion-extension radiographs and subaxial subluxations.

Question 81

Which of the following occurs frequently after nonsurgical management of displaced intra-articular fractures of the calcaneus?

Explanation

Peroneal tendinitis and stenosis are typically seen following nonsurgical management and results from lateral subfibular impingement, whereby the displaced, expanded lateral wall subluxates the peroneal tendons against the distal tip of the fibula or might even dislocate the tendons. Nonsurgical management of displaced calcaneal fractures offers little chance for return to normal function because of the development of a calcaneal malunion. The articular surface is not reduced, the heel remains shortened and widened, the talus is dorsiflexed in the ankle mortise, and the displaced lateral wall causes impingement and binding of the peroneal tendons.

Question 82

Four weeks after undergoing elective THA, an 80-year-old man is in the emergency department with sudden-onset right hip pain and an inability to bear weight after bending over in his garden.

Explanation

DISCUSSION
In Question 138, pain and swelling following a metal-on-metal large-head THA represent a classic presentation for a pseudotumor from metallosis secondary to either articular metal wear or trunnionosis. For this patient, infection should be ruled out with laboratory studies (erythrocyte sedimentation rate and C-reactive protein) and joint aspiration. Metal ion levels and metal artifact reduction sequence MR imaging or ultrasound would be helpful to confirm the diagnosis of pseudotumor. In Question 139, chronic hip pain following elective THA with an antecedent postsurgical wound constitutes a typical presentation for chronic periprosthetic infection. Aseptic loosening could be considered although the timeline is short; bloodwork and joint aspiration would be appropriate investigations. In Question 140, giving way of the knee suggests quadriceps muscle dysfunction likely related to prolonged pressure on the femoral nerve from retractors during a long revision case. The pattern of weakness does not fit a sciatic nerve palsy. In Question 141, the presentation is typical of a prosthetic dislocation, most of which occur during the early postsurgical period following THA.

Question 83

In a patient who has undergone fusion with instrumentation from T4 to the sacrum for adult scoliosis, at which site is a pseudarthrosis most likely to be discovered?

Explanation

DISCUSSION: Although pseudarthrosis can be found anywhere within the spine that has been fused using long multisegmental fixation to the sacrum, it most commonly occurs at the lumbosacral junction. The thoracolumbar junction is another common site of potential pseudarthrosis. In this location, the anatomy changes from lumbar transverse processes to thoracic through the transition zone, and overlying instrumentation often makes it difficult to obtain enough sound bone on decorticated bone to achieve a successful fusion.
REFERENCES: Saer EH III, Winter RB, Lonstein JE: Long scoliosis fusion to the sacrum in adults with nonparalytic scoliosis: An improved method. Spine 1990;15;650-653.
Kostuik JP, Hall BB: Spinal fusions to the sacrum in adults with scoliosis. Spine

1983;8:489-500.
Balderston RA, Winter RB, Moe JH, et al: Fusion to the sacrum for nonparalytic scoliosis in the adult. Spine 1986;11:824-829.

Question 84

A 42-year-old woman underwent an instrumented posterior spinal fusion at L3-S1 with transforaminal lumbar interbody fusion. She had an excellent

Explanation

The MRI scans reveal a postoperative infection. Observation and antibiotics are not appropriate choices. There is a large fluid collection and this requires decompression because the patient has neurologic changes. There is considerable debate regarding the removal of hardware. Many contend that biofilm on the implants can harbor the infection. However, these complications usually can be treated with serial irrigations, debridements, and IV antibiotics. The incidence of infection has been widely studied with varying rates in fusions with instrumentation. Rates appear to be increased with instrumentation, yet these infections usually can be managed without hardware removal.

Question 85

What defect in collagen synthesis is caused by a lack of vitamin C?

Explanation

Scurvy results from vitamin C deficiency. Metabolically, vitamin C deficiency produces a decrease in chondroitin sulfate synthesis (enzymatic impairment of the conversion of glucose to galactosamine) and a deficiency in collagen synthesis by impaired hydroxylation of proline. The greatest problem in collagen synthesis is seen in the metaphysis. The metaphyseal bone becomes weakened and microfracture, hemorrhage, debris, and fibrous tissue accumulates. Collapse of the metaphysis and continued lateral growth produces the typical spurs associated with scurvy.

Question 86

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

Explanation

The muscle transfer procedure most commonly performed for trapezius paralysis is the Eden-Lange procedure. Trapezius paralysis in this patient is secondary to iatrogenic injury to the spinal accessory nerve during lymph node biopsy. In this procedure, the levator scapulae and rhomboid minor and major muscles are transferred laterally. Pectoralis transfer to the inferior border of the scapula is used as a dynamic transfer for serratus anterior winging.

Question 87

A 47-year-old man who works as a carpenter reports a 12-month history of painful mechanical locking of his dominant elbow in the mid range of movement. He also has progressive pain at terminal extension that has not responded to medication, rest, and intra-articular cortisone injection. Active range of movement is from 35 degrees to 130 degrees, and he has full pronation and supination. The ulnar nerve is stable, and he has no subjective or objective neurologic dysfunction in the hand. Radiographs are shown in Figures 22a and 22b. What is the most appropriate treatment? Review Topic

Explanation

The most appropriate treatment is arthroscopic capsular release, loose body removal, and osteophyte decompression. The patient has moderate osteoarthritis of the dominant elbow, with mechanical symptoms suggestive of loose osteochondral body formation. Because the patient has failed to respond to the typical nonsurgical therapeutic options, it is unlikely that further oral medication will be helpful, and job modification may not be practical at this stage. Soft-tissue arthroplasty may be reasonable to consider when less invasive methods, such as arthroscopy, fail. Isolated radial head arthroplasty would not sufficiently address the symptoms. Total elbow arthroplasty is indicated in cases of more advanced disease in older patients with lower physical demands.

Question 88

A 25-year-old athlete presents with symptoms attributed to injury to ligament D in Figure A. Which of the following symptoms and signs is characteristic of this injury? Review Topic

Explanation

This patient has rupture of the lateral ulnar collateral ligament (LUCL), producing posterolateral rotatory instability (PLRI). This is best demonstrated with a positive lateral pivot shift test.
PLRI can be diagnosed using the lateral pivot shift or posterolateral drawer. According to O’Driscoll, the elbow dislocates in 3 stages from lateral to medial (circle of Horii). Stage 1 involves disruption of the LUCL and partial/total disruption of the LCL complex (creating PLRI). Patients have pain with varus stress. Stage 2 includes disruption of the anterior capsule from incomplete elbow posterolateral dislocation. Stage 3 is divided into:
(a) Disruption of all soft tissues surrounding/ including the posterior MCL except for the anterior bundle. This bundle forms the pivot around which the elbow dislocates in a posterior direction by way of a posterolateral rotatory mechanism; and (b) complete disruption of the MCL.
O'Driscoll et al. describe PLRI diagnosed in 5 patients who had elbow dislocation using the posterolateral rotatory instability test, which they describe as being analogous to the test for lateral rotatory instability of the knee after ACL rupture. They believed the condition was laxity of the LUCL, which allowed transient rotatory subluxation of the ulnohumeral joint and secondary dislocation of the radiohumeral joint, without radio-ulnar joint dislocation. They recommended repair of the LUCL to eliminate PLRI.
Sanchez-Sotelo et al. retrospectively described 12 cases of direct repair and 33 ligamentous reconstructions for PLRI. 86% were satisfied with the procedure. Better results were obtained with patients with post-traumatic etiology, instability at presentation, and those with augmented reconstruction with tendon graft (compared with ligament repair alone).
Figure A shows structures on the lateral side of the elbow. The corresponding labels are seen in Illustration A. Illustration B shows the lateral pivot shift (also known as the posterolateral rotatory instability test).
Incorrect Answers:

Question 89

A 9-year-old boy falls from a scooter and sustains the injury shown in the radiographs in Figure 26. After closed reduction and cast immobilization, what is the most likely complication that can result? Review Topic

Explanation

The radiographs show a fracture of the distal radius and ulna physis. The most likely complication is growth arrest of the distal ulna. In contradistinction to physis fractures of the radius (growth arrest incidence of less than 5%), the incidence of growth arrest in the ulna is between 30% and 40%. Entrapment of the EPL tendon and cross union between the two bones is extremely rare.

Question 90

Which of the following cardiac conditions is considered an absolute contraindication to vigorous exercise?

Explanation

DISCUSSION: Hypertrophic cardiomyopathy (HCM) accounts for up to 50% of cases of
sudden death in young athletes. HCM phenotype becomes evident by age 13 to 14 years. Those at higher risk include individuals with cardiac symptoms, a family history of inherited cardiac disease, and those with a family history of premature sudden death. Echocardiography is useful for detecting structural heart disease, including the cardiomyopathies and valvular abnormalities. Trained adolescent athletes demonstrated greater absolute left ventricular wall thickness (LVWT) compared to controls. HCM should be considered in any trained adolescent male athlete with a LVWT of more than 12 mm (female of more than 11 mm) and a nondilated ventricle. Adolescent and adult athletes differ with respect to the range of LVWT measurements, as a manifestation of left ventricular hypertrophy (LVH). Differentiating LVH (“athlete’s heart”) from HCM involves looking at additional echocardiographic features. Sharma and associates reported that adolescents with HCM had a small or normal-sized left ventricle (less than 48 mm) chamber size, while those with LVH had a chamber size at the upper limits of normal (52 mm to 60 mm).
REFERENCES: Sharma S, Maron BJ, Whyte G, et al: Physiologic limits of left ventricular hypertrophy in elite junior athletes: Relevance to differential diagnosis of athlete’s heart and hypertrophic cardiomyopathy. J Am College Cardiol 2002;40:1431-1436.
Maron BJ, Spirito P, Wesley Y, et al: Development and progression of left ventricular hypertrophy in children with hypertrophic cardiomyopathy. N Engl J Med 1986;315:610-614.
Pelliccia A, Culasso F, Di Paolo FM, et al: Physiologic left ventricular cavity dilatation in elite athletes. Ann Intern Med 1999;130:23-31.

Question 91

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

Explanation

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

Question 92

A 54-year-old woman sustained an elbow injury 3 months ago that was treated with open reduction and internal fixation. She now reports pain and limited elbow motion. Radiographs are shown in Figures 10a and 10b. Treatment should now consist of

Explanation

DISCUSSION: Radiographs reveal malunion of a Monteggia fracture-dislocation. Dislocation of the posterior radial head is caused by the malunited ulnar fracture. The deformity includes shortening with an apex posterior angulation. In the acute setting, open reduction of the radial head rarely is necessary; however, in chronic dislocations, open reduction is required. Without ulnar osteotomy, recurrent radial head dislocation is likely.
REFERENCE: Horii E, Nakamura R, Koh S, et al: Surgical treatment for chronic radial head dislocation. J Bone Joint Surg Am 2002;84:1183-1188.

Question 93

Figure 27 shows the radiograph of a 26-year-old man who sustained a closed head injury and a closed elbow dislocation 6 weeks ago. Examination reveals 65 degrees to 115 degrees of flexion, and intensive physical therapy has resulted in no improvement. A decision regarding the timing of surgical correction of the contracture should be based on

Explanation

DISCUSSION: The patient has heterotopic ossification, a more common finding in patients who have sustained head injuries. Treatment will require removal of the heterotopic bone and anterior and posterior capsulectomies. The main concern about timing is the possible recurrence of heterotopic bone. While an extended wait was once thought necessary, this is no longer true. The timing is based on the time since injury and evidence of bone maturation on plain radiographs. A sharp marginal demarcation of the new bone and a trabecular pattern within it are usually present 3 to 6 months after onset, indicating that it is safe to proceed with surgical excision. It is not necessary to wait more than 6 months. Bone scan results are not good indicators because they may remain “hot” for long periods of time. The levels of alkaline phosphatase and serum calcium-phosphorus product do not need to be measured.
REFERENCE: Norris TR (ed): Orthopaedic Knowledge Update: Shoulder and Elbow. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1997, pp 325-335.

Question 94

During surgical treatment of the most common variation of distal femoral "Hoffa" fractures, which of the following orientations for screw fixation should be used?

Explanation

DISCUSSION: The most common variation of a Hoffa fracture is a coronal fracture of the lateral femoral condyle. The most appropriate screw placement of the above answer choices in the treatment of the most common Hoffa fracture variant would be anterior to posterior screws across the lateral condyle for fixation.
Hoffa fractures are coronally oriented fractures of the femoral condyles, with most occurring in the lateral condyle. They are commonly associated with high-energy fractures of the distal femur and can often be overlooked during the assessment and treatment of distal femur fractures. Hoffa fractures are best evaluated using CT scans.
Nork et al. studied the association of supracondylar-intercondylar distal femoral fractures and coronal plane fractures. Of 202 supracondylar-intercondylar distal femoral fractures, they found coronal plane fractures were diagnosed in 38%. A coronal fracture of the lateral femoral condyle was involved more frequently than the medial condyle. Eighty-five percent of these coronal fractures involved a single lateral femoral condyle.
Holmes et al. looked at five cases of coronal fractures of the femoral condyle. All cases received open reduction and internal fixation with lag screws through a formal parapatellar approach. They reported good results with all fractures healing within 12 weeks without complications with final range of motion at least 0 degrees to 115 degrees.

Question 95

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

Explanation

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

Question 96

The flap shown in the clinical photograph seen in Figure 51 is based on what arterial supply?

Explanation

DISCUSSION: The groin flap is based on the superficial circumflex iliac artery, an axial flap that has been a mainstay of providing soft-tissue coverage of the upper extremity. Flaps as large as 35 cm in length and 15 cm in width have been reported. An advantage of the flap is that when used as a pedicle flap, the donor site can be closed directly. A disadvantage of the flap is that it can be quite bulky and can have a thick layer of subcutaneous fat. The superficial circumflex iliac artery travels lateral and superficial to the fascia and below and parallel to the inguinal ligament. It is helpful to elevate the fascia at the medial border of the sartorius muscle to include the deep and superficial branches of the artery for improved flap survival.
REFERENCES: McGregor IA, Jackson IT: The groin flap. Br J Plast Surg 1972;25:3-9.
Lister GD, McGregor IA Jackson IT: The groin flap in hand injuries. Injury 1973;4:229.

Question 97

A 50-year-old patient underwent multiple debridements for an open radial shaft fracture with bone loss. The bed currently shows no evidence of infection but has a 14-cm diaphyseal bone defect. The most appropriate treatment includes open reduction and internal fixation along with

Explanation

The decision to perform fasciotomy of the fingers for a hand compartment syndrome is most appropriately made using
A. clinical examination.
B. invasive pressure measurement.
C. arterial Doppler study.
D. MRI.
Compartment syndrome of the hand can result from a variety of factors, including a traumatic event such as crush injury, fracture, vascular insult, a high-pressure injection injury, or an insect or spider bite. The treatment involves decompressive fasciotomy of the involved compartments. The diagnosis of hand compartment syndrome is determined by history, examination, and objective testing. Patients experience pain out of proportion to the injury, along with swelling and tense skin. Pain may occur with passive motion of the metacarpophalangeal joints as the intrinsic muscles are stretched. Invasive intracompartmental pressures can be measured in the compartments of the hand but not in the fingers. Arterial Doppler studies assess arterial blood flow,
and an abnormality would be a late finding. 41
MRI would show edema of the hand and fingers, but the decision to perform surgical release is less likely made from the findings. The most appropriate method of determining the need for finger fasciotomy is the history and physical examination.
45- Figures 1 and 2 show the MRI studies of a 35-year-old manual laborer with persistent wrist pain despite immobilization. At the time of surgery, collapse of the capitate and arthritic changes of the midcarpal joint are noted. What is the most appropriate procedure for this condition?
A. Local vascularized bone graft
B. Proximal row carpectomy
C. Midcarpal fusion
D. Total wrist arthroplasty
The T1-weighted MRI reveals decreased signal that is consistent with avascular necrosis (AVN) of the capitate. Figure 2 demonstrates increased signal of the capitate consistent with edema. The etiology of AVN of the capitate may be related to trauma, abnormal interosseous vascular supply, and hypermobility. Surgical treatment is considered for patients who have had persistent symptoms despite immobilization. At the time of surgery, collapse of the capitate and arthritic changes would be treated most appropriately with a salvage procedure. A midcarpal fusion is a motion-preserving salvage procedure and is the most appropriate option given to address the pain associated with the midcarpal arthritic changes. The alternative options are not appropriate for this patient. Local vascularized bone grafts are considered for situations in which no evidence of capitate collapse or arthritis is observed.

Question 98

A 50-year-old patient who plays tennis sustained the deformity shown in Figure 27 following a high volley. Further diagnostic work-up should include

Explanation

DISCUSSION: The patient has a rupture of the long head of the biceps; however, patients older than age 45 years are at greater risk of having an associated rotator cuff tear. An MRI scan should be ordered to avoid missing concomitant rotator cuff pathology. While patients may report pain radiating down the arm at the time of the tendon rupture, an EMG is not indicated. The short head of the biceps is intact and needs no further work-up, even though the muscle descends in most cases. The anterior labrum can be injured but is not associated with this deformity.
REFERENCES: Neer CS II, Bigliani LU, Hawkins RJ: Rupture of the long head of the biceps related to the subacromial impingement. Orthop Trans 1977;1:114.
Hawkins RJ, Murnaghan JP: The shoulder, in Gruess RL, Ronnie WRJ (eds): Adult Orthopaedics. New York, NY, Churchill Livingstone, 1984, pp 945-1054.

Question 99

A 43-year-old woman has had pain in the left hip for the past 2 months. A radiograph, CT scan, MRI scan, and biopsy specimens are shown in Figures 16a through 16e. What is the most likely diagnosis?

Explanation

DISCUSSION: The imaging studies are consistent with a chondrosarcoma. The radiograph shows a radiolucent lesion in the pelvis, and there are stippled calcifications on the CT scan. The histology shows a low-grade cellular hyaline cartilage neoplasm with stellate, occasionally binucleated chondrocytes. Enchondroma has a more benign histologic appearance.
REFERENCE: Mirra JM, Gold R, Downs J, Eckardt JJ: A new histologic approach to the differentiation of enchondroma and chondrosarcoma of the bones: A clinicopathologic analysis of 51 cases. Clin Orthop 1985;201:214-237.

Question 100

What is the most important feature in choosing an outcome instrument to assess shoulder disorders?

Explanation

DISCUSSION: There has been a recent increase in the use of outcome instruments to document and measure effects of treatment of medical conditions, including shoulder disorders. The most important feature of an instrument is whether it actually measures what it purports to measure; this is defined as its validity.
REFERENCES: Leggin BG, Iannotti JP: Shoulder outcome measurement, in Iannotti JP, Williams GR (eds): Disorders of the Shoulder: Diagnosis and Management. Philadelphia, PA, Lippincott Williams and Wilkins, 1999, p 1027.
Norris TR (ed): Orthopaedic Knowledge Update: Shoulder and Elbow. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1997, pp 47-55.

Full Question & Answer Text (for Search Engines)

Question 1:

Options:

protected weight bearing and anti-inflammatory drugs.
core decompression of the femoral head.
vascularized free fibular grafting to the femoral head.
bipolar hemiarthroplasty of the hip.
total hip arthroplasty.

Correct Answer: protected weight bearing and anti-inflammatory drugs.

Explanation:

DISCUSSION: The MRI findings show highly increased signal through the entire femoral head and neck on STIR imaging, diagnostic of transient osteoporosis of the femoral head. This disease entity can be seen in middle-aged men, and should be treated nonsurgically. The natural history is that of self-resolution.
REFERENCES: Guerra JJ, Steinberg ME: Distinguishing transient osteoporosis from avascular necrosis of the hip. J Bone Joint Surg Am 1995;77:616-624.
Urbanski SR, de Lange EE, Eschenroeder HC Jr: Magnetic resonance imaging of transient osteoporosis of the hip: A case report. J Bone Joint Surg Am 1991;73:451-455.

Question 2:

When an acute infection of a total elbow arthroplasty is managed with irrigation and debridement, which of the following organisms is associated with the highest risk of persistent infection?

Options:

Enterococcus cloacae
Klebsiella
Staphylococcus aureus
Staphylococcus epidermidis
Streptococcus

Correct Answer: Staphylococcus epidermidis

Explanation:

DISCUSSION: Salvage of a total elbow arthroplasty is possible with early aggressive management of acute infection (symptoms for less than 30 days) with serial irrigation and debridement and antibiotic bead placement. This form of treatment is indicated when there are no radiographic or intraoperative signs of loosening. However, successful treatment is largely dependent on the organism. Staphylococcus epidermidis is associated with persistent infection because it is an encapsulating organism, and it is best treated with implant removal and
IV antibiotics.
REFERENCES: Yamaguchi K, Adams RA, Morrey BF: Infection after total elbow arthroplasty. J Bone Joint Surg Am 1998;80:481-491.
Schoifet SD, Morrey BF: Treatment of infection after total knee arthroplasty by debridement with retention of the components. J Bone Joint Surg Am 1990;72:1383-1390.

Question 3:

Options:

MRI
Surgical intervention
Activity modification
Cast immobilization

Correct Answer: Activity modification

Explanation:

Question 4:

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

Options:

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

Correct Answer: Early hip spica casting

Explanation:

Question 5:

Options:

Lateral plantar artery
Tibial nerve
First branch of the lateral plantar nerve
Sural nerve
Flexor hallucis brevis muscle

Correct Answer: First branch of the lateral plantar nerve

Explanation:

Question 6:

Options:

casting.
closed reduction, casting, and no weight bearing for 6 weeks.
open reduction and internal fixation.
closed reduction and percutaneous Kirschner wire fixation.
closed reduction and percutaneous screw fixation.

Correct Answer: open reduction and internal fixation.

Explanation:

DISCUSSION: Myerson and associates studied the outcomes of 19 patients with tarsometatarsal joint injuries during athletic activity. Injuries were classified as first- or second-degree sprains of the tarsometatarsal joint or a third-degree sprain with diastasis between the metatarsals or cuneiforms. Poor functional results were seen in those with a delay in diagnosis and with inadequate treatment. For patients with third-degree sprains, poor results were obtained with nonsurgical management. These patients required open reduction and internal fixation for optimal return to function. The anatomic reduction is critical to the outcome; therefore, open reduction is preferred.
REFERENCES: Baxter DE: The Foot and Ankle in Sport, ed 1. St Louis, MO, Mosby, 1995,
pp 107-123.
Curtis MJ, Myerson M, Szura B: Tarsometatarsal joint injuries in the athlete. Am J Sports Med 1993;21:497-502.
Kuo RS, Tejwani NC, DiGiovanni CW, et al: Outcome after open reduction and internal fixation of Lisfranc joint injuries. J Bone Joint Surg Am 2000;82:1609-1618.
Thompson MC, Mormino MA: Injury to the tarsometatarsal joint complex. J Am Acad Orthop Surg 2003;11:260-267.

Question 7:

A 6-year-old boy has leg pain. A radiograph, MRI, CT, and bone scans, and a biopsy specimen are shown in Figures 14a through 14e. What is the most likely diagnosis?

Options:

Ewing’s sarcoma
Osteomyelitis
Osteosarcoma
Eosinophilic granuloma
Fibrous dysplasia

Correct Answer: Osteomyelitis

Explanation:

Question 8:

Following ankle arthroscopy performed through a posterolateral portal, a patient notes numbness on the lateral half of the heel pad of the foot. What is the most likely injured structure?

Options:

Sural nerve
Lateral plantar nerve
Lateral calcaneal nerve
First branch of the lateral plantar nerve
Deep peroneal nerve

Correct Answer: Lateral calcaneal nerve

Explanation:

DISCUSSION: The lateral calcaneal nerve is a branch of the sural nerve that runs along the lateral border of the Achilles tendon to innervate the lateral heel pad. Ankle arthroscopy involves posterior portals that hug the Achilles tendon to avoid the main trunks of the sural nerve and tibial nerve; however, the lateral calcaneal branch remains potentially vulnerable. The first branch of the lateral plantar nerve is actually a medial structure that partially innervates the plantar fascia and the abductor digiti quinti. The deep peroneal nerve is anterior to the ankle.
REFERENCES: Sitler DF, Amendola A, Bailey CS, et al: Posterior ankle arthroscopy:
An anatomic study. J Bone Joint Surg Am 2002;84:763-769.
Sarrafian SK: Anatomy of the Foot and Ankle, Descriptive, Topographic, Functional, ed 2. Philadelphia, PA, JB Lippincott, 1993, p 361.

Question 9:

Options:

Custom-molded night orthotics
Double osteotomy of the first metatarsals
Crescentic osteotomy of the first metatarsals
Distal realignment (modified McBride)
First metatarsophalangeal joint arthrodeses

Correct Answer: First metatarsophalangeal joint arthrodeses

Explanation:

DISCUSSION: While other surgeries have provided some success, first metatarsophalangeal joint arthrodesis has the highest overall success rate compared to other surgeries in ambulatory and nonambulatory children with cerebral palsy. The recurrence rate is unacceptably high with the other procedures listed above. In contrast, neurologically normal children are amenable to osteotomies and soft-tissue procedures.
REFERENCES: Davids JR, Mason TA, Danko A, et al: Surgical management of hallux valgus deformity in children with cerebral palsy. J Pediatr Orthop 2001;21:89-94.
Jenter M, Lipton GE, Miller F: Operative treatment for hallux valgus in children with cerebral palsy. Foot Ankle Int 1998;19:830-835.

Question 10:

Options:

excision of the osteophytes and loose bodies and anterior and posterior capsular releases.
removal of the loose bodies.
anterior capsular release.
anterior and posterior capsular releases.
interposition arthroplasty.

Correct Answer: excision of the osteophytes and loose bodies and anterior and posterior capsular releases.

Explanation:

Question 11:

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

Options:

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

Correct Answer: Proximal femoral replacement arthroplasty

Explanation:

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

Question 12:

Options:

Nonossifying fibroma
Fibrous dysplasia
Unicameral bone cyst
Osteogenesis imperfecta
Osteofibrous dysplasia

Correct Answer: Osteofibrous dysplasia

Explanation:

Question 13:

Options:

Lacertus fibrosis contracture
Intra-articular loose bodies 74
Olecranon fossa impingement
Radiocapitellar plica

Correct Answer: Radiocapitellar plica

Explanation:

DISCUSSION
The MRI studies show a radiocapitellar plica. This anomalous structure has been associated with symptomatic snapping. Lacertus fibrosis contracture will not cause painful snapping. An intra-articular pathology such as loose bodies is not present on these imaging studies. Olecranon fossa impingement causes posterior pain in extension and is not shown in the images.
RECOMMENDED READINGS
Antuna SA, O'Driscoll SW. Snapping plicae associated with radiocapitellar chondromalacia. Arthroscopy. 2001 May;17(5):491-5. PubMed 11337715.
View Abstract
at PubMed
Ruch DS, Papadonikolakis A, Campolattaro RM. The posterolateral plica: a cause of refractory lateral elbow pain. J Shoulder Elbow Surg. 2006 May-Jun;15(3):367-70. PubMed PMID: 16679240.
View Abstract at PubMed

Question 14:

Options:

Anterior labral repair
Anterior labral repair and remplissage
Posterior labral repair and rotator interval closure
Anterior and posterior labral repair

Correct Answer: Anterior and posterior labral repair

Explanation:

Question 15:

In a locking plate screw construct, axial forces are borne by which of the following?

Options:

Plate
Screw closest to the fracture
Screw most distal to the fracture
Bone-plate interface
Opposite cortex

Correct Answer: Plate

Explanation:

Question 16:

Options:

Femoral nerve palsy
Sciatic nerve palsy
Recurrent hip dislocation
Osteonecrosis of the femoral head
Immediate chondrolysis of the hip joint

Correct Answer: Osteonecrosis of the femoral head

Explanation:

Question 17:

Which of the following factors is associated with failure of arthroscopic excision of the distal clavicle?

Options:

Removal of less than 2 cm of bone
Male gender
Female gender
Diagnosis of osteolysis
Uneven resection of bone

Correct Answer: Uneven resection of bone

Explanation:

Question 18:

Options:

repeat the examination in a few hours.
remove the left knee immobilizer and flex the knee.
apply long leg casts that include the feet.
obtain an electromyogram and nerve conduction velocity studies.
perform peroneal nerve exploration.

Correct Answer: remove the left knee immobilizer and flex the knee.

Explanation:

Question 19:

Communication breakdown is the leading cause of which of the following?

Options:

Delayed diagnoses
Medication errors
Surgical site infections
1 and 2
All of the above

Correct Answer: Delayed diagnoses

Explanation:

Question 20:

Options:

Total shoulder arthroplasty
Hemiarthroplasty with glenoid interposition
Surface replacement hemiarthroplasty
Arthroscopic debridement
Anti-inflammatory drugs and a range-of-motion stretching program

Correct Answer: Anti-inflammatory drugs and a range-of-motion stretching program

Explanation:

DISCUSSION: New onset pain and stiffness in the young arthritic shoulder is a difficult problem to treat. Initial management should be aimed at reducing pain and improving motion in all planes. This patient’s activities and age preclude a shoulder arthroplasty at this time. If nonsurgical management fails to provide relief, then arthroscopic debridement and capsular release may be beneficial.
REFERENCES: Norris TR (ed): Orthopaedic Knowledge Update: Shoulder and Elbow 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 257-266.
Skedros JG, O’Rourke PJ, Zimmerman JM, et al: Alternatives to replacement arthroplasty for glenohumeral arthritis, in Iannotti JP, Williams GR (eds): Disorders of the Shoulder: Diagnosis and Management. Philadelphia, PA, Lippincott Williams & Wilkins, 1999, pp 485-499.

Question 21:

Figures 20a and 20b show the radiographs of an obese 15-year-old boy who has severe left groin pain and is unable to bear weight following a minor injury. Treatment should consist of

Options:

fixation with one or two screws.
cast immobilization.
manipulative reduction with single screw fixation.
in situ fixation with multiple screws.
open epiphyseodesis.

Correct Answer: fixation with one or two screws.

Explanation:

Question 22:

Options:

Lateral collateral ligament
Tibial spine
Medial meniscus
Anterior cruciate ligament (ACL)

Correct Answer: Anterior cruciate ligament (ACL)

Explanation:

Question 23:

Options:

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

Correct Answer: Spontaneous subluxation of the right sternoclavicular joint

Explanation:

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

Question 24:

Options:

Longitudinal split tear in the peroneus longus
Longitudinal split tear in the peroneus brevis
Plantaris
Peroneus accessorius
Peroneus quartus

Correct Answer: Peroneus quartus

Explanation:

DISCUSSION: The structure labeled “A” is a peroneus quartus, a supernumary muscle arising most commonly from the peroneus brevis. The presence of peroneus quartus is not uncommon, with an incidence of up to 21%, and is associated with lateral ankle pain and peroneal tendon symptoms, theoretically as a result of mass effect within the peroneal tendon sheath.
REFERENCES: Zammit J, Singh D: The peroneus quartus muscle: Anatomy and clinical relevance. J Bone Joint Surg Br 2003;85:1134-1137.
Sobel M, Levy ME, Bohne WH: Congenital variations of the peroneus quartus muscle: An anatomic study. Foot Ankle 1990;11:81-89.

Question 25:

Options:

Isthmic spondylolysis
Herniated nucleus pulposus at L5-S1
Lumbar sprain
Limbus fracture
Aseptic diskitis

Correct Answer: Isthmic spondylolysis

Explanation:

Question 26:

Options:

spinal accessory nerve, causing shoulder depression with the scapula translated laterally and the inferior angle rotated laterally.
spinal accessory nerve, causing shoulder elevation with the scapula translated medially and the inferior angle rotated medially.
long thoracic nerve, causing shoulder elevation with the scapula translated medially and the inferior angle rotated medially.
long thoracic nerve, causing shoulder depression with the scapula translated laterally and the inferior angle rotated laterally.
thoracodorsal nerve, causing shoulder depression with the scapula translated laterally and the inferior angle rotated laterally.

Correct Answer: spinal accessory nerve, causing shoulder depression with the scapula translated laterally and the inferior angle rotated laterally.

Explanation:

Question 27:

Options:

Ganglion cyst
Clear cell sarcoma
Epithelioid sarcoma
Epidermal inclusion cyst
Synovial sarcoma

Correct Answer: Clear cell sarcoma

Explanation:

DISCUSSION: The histologic appearance of the soft-tissue lesion reveals compact nests of cells with a clear cytoplasm surrounded by a delicate border of fibrocollagenous tissue. There can be scattered multinucleated giant cells. This is consistent with a clear cell sarcoma, also called malignant melanoma of soft parts. This tumor is usually positive for S-100 and HMB45 (a melanoma-associated antigen). These tumors are frequently found around the foot and ankle. Similar to epithelioid sarcoma, it is usually intimately bound to tendons or tendon sheaths. Often the tumors are present for many years. The classic histologic appearance of this lesion differentiates it from the other choices.
REFERENCES: Enzinger FM, Weiss SW: Soft Tissue Tumors, ed 3. St Louis, MO, Mosby, 1995, p 913.
Lucas DR, Nascimento AG, Sim FH: Clear cell sarcoma of soft tissues: Mayo Clinic experience with 35 cases. Am J Surg Pathol 1992;16:1197-1204.

Question 28:

A 46-year-old woman fell from her bicycle and sustained the injury shown in Figure 24. Which of the following ligaments has been disrupted? Review Topic

Options:

Acromioclavicular
Acromioclavicular and coracoclavicular
Coracoclavicular
Coracoacromial and sternoclavicular
Sternoclavicular

Correct Answer: Acromioclavicular and coracoclavicular

Explanation:

Question 29:

Options:

BMI >30
Presence of secondary changes of the acetabulum
Osteonecrosis of the femoral head
Age of younger than 55 years old
Male gender

Correct Answer: Osteonecrosis of the femoral head

Explanation:

Question 30:

Which of the following imaging modalities is most accurate in locating a toothpick in the plantar arch of the foot?

Options:

Radiograph
CT
MRI
Ultrasound
Bone scan

Correct Answer: Ultrasound

Explanation:

DISCUSSION: Ultrasound is best at imaging abrupt changes in the density of adjacent tissue and therefore is best at imaging wood in the soft tissues of the foot.
REFERENCES: Mizel MS, Steinmetz ND, Trepman E: Detection of wooden foreign bodies in muscle tissue: Experimental comparison of computed tomography, magnetic resonance imaging, and ultrasonography. Foot Ankle Int 1994;15:437-443.
Jacobson JA, Powell A, Craig JG, et al: Wooden foreign bodies in soft tissue: Detection at US. Radiology 1998;206:45-48.

Question 31:

Options:

Flexor hallucis longus and flexor hallucis brevis
Flexor hallucis longus and adductor hallucis
Flexor hallucis brevis and adductor hallucis
Flexor hallucis longus and abductor hallucis
Flexor hallucis brevis and abductor hallucis

Correct Answer: Flexor hallucis brevis and adductor hallucis

Explanation:

DISCUSSION: Owens and Thordardson cautioned surgeons not to release the conjoined tendon from the base of the proximal phalanx of the great toe because of an increased risk of iatrogenic hallux varus. Release of the transverse and oblique heads of the adductor hallucis is largely accomplished by releasing the soft tissue adjacent to the lateral sesamoid, without releasing tissue from the base of the proximal phalanx. The conjoined tendon is made up of the flexor hallucis brevis and the adductor hallucis.
REFERENCES: Owens S, Thordardson DB: The adductor hallucis revisited. Foot Ankle Int 2001;22:186-191.
Sarrafian SK: Anatomy of the Foot and Ankle. Philadelphia, PA, JB Lippincott, 1983, chapter 5.

Question 32:

What is the primary concern for arthrodesis of a failed infected total knee arthroplasty using internal fixation?

Options:

Recurrent infection
Lack of stability
Lack of soft-tissue coverage
Stress shielding
Stress risers

Correct Answer: Recurrent infection

Explanation:

Question 33:

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

Options:

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

Correct Answer: CT scanogram

Explanation:

Question 34:

Which of the following anatomic changes is observed as part of the normal aging process of the adult spine?

Options:

Overall kyphosis gradually decreases.
Overall lumbar lordosis gradually decreases.
The sagittal vertical line dropped from C7 gradually moves posteriorly relative to the sacrum.
Cervical scoliosis develops.
Coronal balance shifts laterally from the midsacrum.

Correct Answer: Overall lumbar lordosis gradually decreases.

Explanation:

Question 35:

Which of the following is a recognized consequence of hip fusion?

Options:

Low back pain
Contralateral knee laxity
Difficulty delivering children
Meralgia paresthetica
Contralateral abductor weakness

Correct Answer: Low back pain

Explanation:

Question 36:

The initiating cellular event in development of posttraumatic osteoarthritis is attributed to which of the following?

Options:

Chondrocyte aging as the result of matrix degradation
Chondrocyte death from apoptosis
Cysteine protease-inhibited chondrocyte destruction
Interleukin-2-mediated chondrocyte hypertrophy

Correct Answer: Chondrocyte death from apoptosis

Explanation:

Question 37:

Which of the following nerves innervates the muscle that originates from the middle third of the dorsal surface of the lateral border of the scapula, as shown in Figure 7?

Options:

Musculocutaneous
Lower subscapular
Axillary
Suprascapular
Infrascapular

Correct Answer: Axillary

Explanation:

Question 38:

Among patients with adolescent idiopathic scoliosis, a thoracolumbosacral orthosis is most effective for which type of curve?

Options:

Apex of the curve is at T3
Apex of the curve is at T8
Apex of the curve is at L1
Apex of the curve is at L2

Correct Answer: Apex of the curve is at T8

Explanation:

DISCUSSION
A thoracolumbosacral orthosis is most effective for bracing of curves when the apex is at T7 or below. Bracing is used for patients who are skeletally immature (Risser stage 0, 1, or 2), and it is recommended that the brace be worn 16 to 23 hours per day and continued until skeletal maturity or until the curve progresses to beyond 45 degrees, at which point bracing is no longer considered effective.
RECOMMENDED READINGS
Luhmann SJ, Skaggs DL: Pediatric spine conditions, in Lieberman JR (ed):
AAOS Comprehensive Orthopaedic Review. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2009, pp 245-265.
Shaughnessy WJ. Advances in scoliosis brace treatment for adolescent idiopathic scoliosis. Orthop Clin North Am. 2007 Oct;38(4):469-75, v. Review. PubMed PMID: 17945126.
View Abstract at PubMed

Question 39:

What is a known risk factor for lateral distal femoral locking plate failure when used for the fixation of comminuted extra-articular fractures?

Options:

Early post-operative knee range of motion
Delayed weightbearing
Short working length of the construct
Bridge plate fixation
Plate-screw density less than 0.5

Correct Answer: Plate-screw density less than 0.5

Explanation:

Question 40:

Options:

C8 - T1 nerve root avulsion 3 months ago
C5 - C6 nerve root avulsion 2 months ago
Upper brachial plexus palsy 22 months ago
Medial and posterior cord injury from gunshot wound 2 months ago
C6 ASIA A spinal cord injury PREFERRED RESPONSE 2 Transfer of fascicles from (1) ulnar nerve to the nerve to the biceps and (2) median nerve to the motor nerve of the brachialis would be appropriate in the treatment of an acute (<3-6 months) upper brachial plexus palsy. Upper trunk injury (C5, C6) often results from the avulsion of both the C5 and C6 nerve roots. Injuries of this nature usually result from a downward force on the shoulder with lateral bending of the cervical spine in the opposite direction. This results in what is commonly called an Erb-Duchenne palsy. Patients often present with a flail shoulder and loss of elbow flexion. Other common treatments for C5 and C6 root avulsion include neurotization of the musculocutaneous (MSC) nerve by the spinal accessory (SA) or intercostal nerve, and neurotization of the supra-scapular nerve by the SA. Liverneaux et al. looked at short term results of (1) ulnar nerve fascicle transfer to the nerve to the biceps and (2) fascicle of the median nerve to the motor branch to the brachialis in 15 patients with acute C5 - C6 nerve root avulsion injuries. Grade 4 elbow flexion was restored in each of the 10 patients. There was no secondary deficit in grip strength or sensation.They concluded that this double nerve transfer technique will likely reduce the need for secondary procedures to augment elbow flexion. Teboul et al. reviewed thirty-two patients with an upper nerve-root brachial plexus injury that underwent ulnar nerve fascicle transfer to the nerve of biceps to restore elbow flexion. After the nerve transfer, twenty-four patients achieved grade 3 elbow flexion strength or better. They note that this procedure will spare the C5 nerve root and other nerves for grafting or transfer elsewhere. Illustration A shows harvesting of an ulnar nerve fascicle for transfer. Illustration B shows transfer of the fascicle of the ulnar nerve to the motor nerve of the biceps. Incorrect Answers:

Correct Answer: C8 - T1 nerve root avulsion 3 months ago

Explanation:

(SBQ12FA.31) A 30-year-old male patient involved in a hang-gliding accident sustains a knee dislocation with multiligamentous knee injury and transection of his peroneal nerve. He undergoes multiple reconstructive surgeries. Two years later, he continues to have a foot drop and dynamic tendon transfer is recommended. This treatment most commonly involves transferring a tendon from which native insertion point to which new insertion point?
Review
Topic
Plantar distal phalanges to medial navicular
Medial navicular to dorsal lateral cuneiform
Plantar 1st metatarsal to dorsal lateral cuneiform
5th metatarsal base to dorsal medial cuneiform
Plantar distal phalanx of the hallux to dorsal distal phalanx of hallux
Dynamic tendon transfer to restore active dorsiflexion of the foot involves transferring the posterior tibial tendon (PTT) insertion on the medial navicular to the dorsal lateral cuneiform.
Common peroneal nerve (CPN) injuries following traumatic knee dislocation are common, with an incidence of 25-40%. CPN palsy is characterized by foot drop due to loss of ankle dorsiflexors with a steppage gait and eventual development of a supinated equinovarus foot secondary to the unopposed pull of the PTT. Nonsurgical management involves use of an ankle-foot orthosis and physical therapy. Surgical
options include acute primary repair, nerve grafting with either autologous sural nerve or nerve conduits and dynamic tendon transfer. The PTT is harvested from its insertion at the navicular, passed through the interosseous membrane (IOM) and anchored to the lateral cuneiform (see Illustration A). The classic bridle procedure involves concomitant anastamosis of the PTT to the tibialis anterior (TA) and peroneus longus (PL) tendons.
Garozzo et al reported a case series of 62 patients with post-traumatic CPN palsy who underwent a one-stage procedure consisting of nerve repair and PTT transfer. Nerve repair combined with PTT transfer improved postoperative outcomes compared to nerve repair alone. At 2-year follow up, neural regeneration was demonstrated in 90% of patients. The authors hypothesized that poor outcomes following nerve repair alone are due to force imbalance between the functioning flexors and paralyzed extensors, which is somewhat equalized by performing a PTT transfer at time of repair.
Niall et al reviewed 55 patients with traumatic knee dislocation and reported a 41% incidence of CPN injury, exclusively associated with dislocations involving disruption of the posterior cruciate ligament (PCL) and posterolateral corner (PLC). Complete neurologic recovery was found in only 21% of patients. The best prognosis was found with lesions in continuity, less than 7cm of nerve involvement, and short conduction block and muscle activity on nerve conduction and EMG studies.
Vigasio et al described a dynamic tendon transfer technique for traumatic complete CPN injury, involving transfer of the PTT to the TA rerouted to a new origin at the lateral cuneiform to restore ankle dorsiflexion and flexor digitorum longus (FDL) to the extensor digitorum longus (EDL) and extensor hallucis longus (EHL) to restore digit dorsiflexion. Rerouting the TA towards the transferred PTT ensures the PTT harvest length is sufficient. This avoids excessive tensioning of the PTT, which may limit tendon excursion and result in a static tenodesis rather than dynamic function, as well as the need for PTT lengthening which may decrease strength of the transfer
Illustration A is a series of intraoperative photographs demonstrating PTT transfer from Garg et al. An incision is made distal to the medial malleolus and the PTT is harvested subperiosteally (A). The PTT is delivered through a second incision ~15cm proximal to the medial malleolus (B-C). The PTT is then passed through the interosseous membrane and out a third incision over the anterior fibula (D). Lastly, the PTT is passed through a fourth incision over the dorsal midfoot and anchored to the lateral cuneiform (E).
Incorrect Responses:
nerve and therefore would not be functional. Answer 5: Transferring the flexor hallucis longus (FHL; insertion = plantar distal phalanx of the hallux) to the insertion of the EHL (dorsal distal phalanx of hallux) is recommended for correction of claw toe deformity and would not help restore foot dorsiflexion in this patient.

Question 41:

Options:

Endoscopy
Gastrostomy
Colonoscopy
Laparotomy

Correct Answer: Colonoscopy

Explanation:

Question 42:

Options:

Electromyography (EMG) and nerve conduction velocity studies (NCVS)
Diagnostic ultrasonography of the patellar tendon
MRI
Continuous passive motion
Knee aspiration

Correct Answer: Knee aspiration

Explanation:

Question 43:

Options:

Anterior sternoclavicular joint dislocation
Posteroinferior sternoclavicular joint dislocation
Anterior acromioclavicular joint dislocation
Posterior acromioclavicular joint dislocation
Acromial fracture

Correct Answer: Anterior sternoclavicular joint dislocation

Explanation:

Question 44:

Options:

Correlation coefficient of MRSA
Prevalence of MRSA
Incidence of MRSA
Relative risk of MRSA

Correct Answer: Prevalence of MRSA

Explanation:

Question 45:

Options:

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

Correct Answer: Total knee replacement

Explanation:

Question 46:

Options:

Biopsy and culture of the lesion
MRI of the left femur
IV antibiotics for 6 weeks
Incision and drainage of the left femur
Repeat radiograph in 3 months

Correct Answer: MRI of the left femur

Explanation:

Question 47:

Options:

Thumb carpometacarpal (CMC) arthroplasty with ligament suspensionplasty
Thumb CMC and thumb metacarpophalangeal (MCP) joint fusion
Thumb CMC arthroplasty with ligament suspensionplasty and thumb MCP joint stabilization
Trapezial resection and distraction arthroplasty

Correct Answer: Thumb CMC arthroplasty with ligament suspensionplasty and thumb MCP joint stabilization

Explanation:

Question 48:

Options:

observation.
dynamic splinting.
resection of the synostosis.
proximal radial excision.
forearm osteotomy.

Correct Answer: resection of the synostosis.

Explanation:

Question 49:

Options:

Removal of hardware with tendon transfer
Repair of the extensor pollicis longus (EPL) tendon primarily
Thumb interphalangeal (IP) arthrodesis
Nonsurgical treatment with cast placement keeping the thumb in a fully extended position for 4 weeks

Correct Answer: Removal of hardware with tendon transfer

Explanation:

Question 50:

Which of the following factors has the greatest effect on the pull-out strength of a lumbar pedicle screw?

Options:

Depth of vertebral body penetration
Percentage of pedicle filled by the screw
Bone mineral density
Tapping of the pedicle
Screw diameter

Correct Answer: Bone mineral density

Explanation:

Question 51:

Sudden cardiac death in the young athlete is most frequently caused by

Options:

hypertrophic cardiomyopathy.
active myocarditis.
mitral valve prolapse.
aortic rupture.
coronary artery disease.

Correct Answer: hypertrophic cardiomyopathy.

Explanation:

Question 52:

What is the most common cause for poor outcomes in patients who undergo total shoulder arthroplasty? Review Topic

Options:

Loosening of the humeral component
Loosening of the glenoid component
Infection
Brachial plexus injury
Rotator cuff tear

Correct Answer: Rotator cuff tear

Explanation:

Question 53:

Options:

discharge at this time may result in loss of motion and the necessity of manipulation under anesthesia.
the insurance company has no right to make such demands on the surgeon or the patient.
if the patient is discharged and fails to regain full motion, she will most likely file a suit against the insurance company.
the patient will require a follow-up examination in 6 weeks to evaluate her progress.
the patient will be given an extra set of exercises to perform at home.

Correct Answer: discharge at this time may result in loss of motion and the necessity of manipulation under anesthesia.

Explanation:

Question 54:

Options:

Tumor grade
Tumor size
Surgical margin
Anatomic site of the tumor
Histologic subtype of the tumor

Correct Answer: Surgical margin

Explanation:

Question 55:

What is the most appropriate surgical treatment for a stage III symptomatic scapholunate advanced collapsed (SLAC) wrist?

Options:

Radioscapholunate arthrodesis
Scaphotrapeziotrapezoid arthrodesis
Scaphocapitate arthrodesis
Proximal row carpectomy
Scaphoid excision and capitate-lunate-triquetrum-hamate arthrodesis

Correct Answer: Scaphoid excision and capitate-lunate-triquetrum-hamate arthrodesis

Explanation:

DISCUSSION: SLAC is the end result of chronic scapholunate instability. The arthritis follows a predictable pattern. Stage I disease involves cartilage loss between the waist of the scaphoid and the radial styloid. In stage II, the arthritis progresses to include the proximal pole of the scaphoid and the scaphoid fossa of the radius. Finally, stage III goes on to include arthritis of the capitolunate joint. The only treatment option that addresses all of the sites of arthritis is the scaphoid excision and four corner fusion.
REFERENCES: Ashmead DT IV, Watson HK, Damon C, et al: Scapholunate advanced collapse wrist salvage. J Hand Surg Am 1994;19:741-750.
Sauerbier M, Trankle M, Linsner G, et al: Midcarpal arthrodesis with complete scaphoid excision and interposition bone graft in the treatment of advanced carpal collapse (SNAC/SLAC wrist): Operative technique and outcome assessment. J Hand Surg Br 2000;25:341-345.

Question 56:

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

Options:

Warfarin
Low-molecular-weight heparin
Rivaroxaban
Aspirin

Correct Answer: Rivaroxaban

Explanation:

Question 57:

Options:

Flexor tendons
Lateral band
Lumbrical
Volar plate

Correct Answer: Volar plate

Explanation:

Question 58:

Options:

talectomy.
reimplantation of the talus.
reimplantation of the talus with acute triple arthrodesis.
Syme amputation.
transtibial amputation.

Correct Answer: reimplantation of the talus.

Explanation:

DISCUSSION: The radiograph shows a complete extrusion of the talus. Reimplantation of the talus after wound debridement has been reported to be safe and successful, and provides for flexibility with any future reconstructive procedures.
REFERENCES: Smith CS, Nork SE, Sangeorzan BJ: The extruded talus: Results of reimplantation. J Bone Joint Surg Am 2006;88:2418-2424.
Brewster NT, Maffulli N: Reimplantation of the totally extruded talus. J Orthop Trauma 1997;11:42-45.

Question 59:

Options:

A 270-degree labral tear
His intention to continue contact sport activities
Anterior bony loss measuring 30% of inferior glenoid width
An inferior glenohumeral ligament avulsion (HAGL) lesion

Correct Answer: Anterior bony loss measuring 30% of inferior glenoid width

Explanation:

DISCUSSION
There is much debate in the literature regarding optimal techniques for treatment of shoulder instability. Although some studies suggest that open stabilization may result in lower recurrence rates in contact athletes, this approach is now under scrutiny. Extensive labral involvement (posterior labral involvement in this scenario) is likely more accessible via arthroscopic methods. Although HAGL lesions may be more easily accessible via an open approach (particularly for inexperienced arthroscopists), numerous authors describe successful repair via arthroscopic techniques. Among these responses, the strongest indication for an open approach, including possible bony transfer, is high-grade glenoid bone loss. Although the critical amount of bone loss is a topic of debate, most surgeons and authors suggest a cutoff of 20% to 25%.
CLINICAL SITUATION FOR QUESTIONS 90 THROUGH 92
Figure 90 is the radiograph of a 14-year-old pitcher who plays in a year-round baseball program and has vague pain in his dominant shoulder. The pain occurs with throwing, and it has been worsening for 2 months. Pain typically occurs during the late cocking phase of throwing. He has no tenderness of the rotator cuff and 5/5 rotator cuff strength. His arc of motion is symmetric between his dominant and nondominant arms. The sulcus sign is negative.

Question 60:

Options:

Rest, nonsteroidal anti-inflammatory drugs, rehabilitation, and gradual return to play
Aspiration of the symphysis pubis followed by an appropriate course of antibiotics
Referral to a general surgeon for hernia evaluation
Rigid plating across the symphysis to address instability
MRI evaluation of the symphysis

Correct Answer: Rest, nonsteroidal anti-inflammatory drugs, rehabilitation, and gradual return to play

Explanation:

Question 61:

During an anterior approach to the shoulder, excessive traction on the conjoined tendon is most likely to result in loss of

Options:

elbow flexion.
shoulder flexion.
shoulder internal rotation.
shoulder abduction.
forearm pronation.

Correct Answer: elbow flexion.

Explanation:

Question 62:

What is the structure indicated by the letter “A” in Figure A? Review Topic

Options:

Annular ligament
Lateral ulnar collateral ligament
Accessory collateral ligament
Radial collateral ligament
Transverse ligament

Correct Answer: Radial collateral ligament

Explanation:

Question 63:

Options:

In situ glenoid component implantation
Hemiarthroplasty
Eccentric reaming of glenoid
Posterior glenoid bone graft

Correct Answer: Eccentric reaming of glenoid

Explanation:

Question 64:

Options:

chemotherapy.
radiation therapy.
marginal excision.
wide excision.
above-knee amputation.

Correct Answer: marginal excision.

Explanation:

Question 65:

Options:

debridement of the biceps tendon.
debridement of the rotator cuff tear.
repair of the biceps pulley system.
repair of the rotator cuff tear.
tenodesis of the biceps tendon.

Correct Answer: tenodesis of the biceps tendon.

Explanation:

Question 66:

Options:

Lateral facet articular cartilage of the patella
Peroneal nerve
Superior lateral geniculate artery
Inferior lateral geniculate artery
Lateral collateral ligament femoral insertion

Correct Answer: Superior lateral geniculate artery

Explanation:

Question 67:

Options:

Snug fitting shoe to block side-to-side motion that is common after this procedure
Leather sole shoe to prevent catching the shoe on carpet which is common with crepe-soled shoes
Lateral wedge on the shoe to offset the external rotation during the toe-off phase of gait commonly seen after this procedure
Steel shank to extend the foot lever and prevent deformity at the toe break
Custom-made shoe to provide the best possible fit and function

Correct Answer: Steel shank to extend the foot lever and prevent deformity at the toe break

Explanation:

DISCUSSION: The steel shank is a flat 1-inch steel strip placed between layers of the shoe to extend the foot lever and prevent deformity at the toe break seen following a partial first ray amputation. A rocker sole may be added as well to facilitate transition from foot flat to the toe-off phase of gait. Proper shoe fit is important, but “snug” fitting shoes in a patient with peripheral neuropathy and likely fluctuations in volume from intermittent swelling are to be avoided. A custom shoe is an unnecessary expense. The patient has at least 10 degrees of dorsiflexion at the ankle with an intact anterior tibialis muscle; therefore, catching the sole on carpeting should not be a problem.
REFERENCES: Philbin TM, Leyes M, Sferra JJ, et al: Orthotic and prosthetic devices in partial foot amputations. Foot Ankle Clin 2001;6:215-228.
Pinzur MS, Dart HC: Pedorthic management of the diabetic foot. Foot Ankle Clin 2001;6:205-214.

Question 68:

What range of motion parameters are required for a patient with posttraumatic elbow stiffness to accomplish all the normal activities of daily living?

Options:

Flexion and extension of 10 degrees to 110 degrees, pronation of 50 degrees, and supination of 50 degrees
Flexion and extension of 10 degrees to 130 degrees, pronation of 50 degrees, and supination of 50 degrees
Flexion and extension of 30 degrees to 110 degrees, pronation of 60 degrees, and supination of 30 degrees
Flexion and extension of 30 degrees to 130 degrees, pronation of 50 degrees, and supination of 50 degrees
Flexion and extension of 30 degrees to 130 degrees, pronation of 60 degrees, and supination of 30 degrees

Correct Answer: Flexion and extension of 30 degrees to 130 degrees, pronation of 50 degrees, and supination of 50 degrees

Explanation:

Question 69:

Options:

Superior labral detachment
Os acromiale
Partial-thickness rotator cuff tear on the articular side
Medial subluxation of the long head of the biceps
Moderate arthrosis of the glenohumeral joint

Correct Answer: Partial-thickness rotator cuff tear on the articular side

Explanation:

Question 70:

Which of the following physical examination findings is most likely present in the condition producing the MRI findings shown in Figure 92? Review Topic

Options:

Valgus laxity at 30 degrees of knee flexion
Varus laxity at 30 degrees of knee flexion
Posterior drawer
Pivot shift
Patellar apprehension

Correct Answer: Pivot shift

Explanation:

Question 71:

Anterior penetration of an iliosacral screw through the sacral ala would most likely lead to weakness of which of the following movements?

Options:

Hip flexion
Hip adduction
Knee extension
Ankle plantarflexion
Great toe dorsiflexion

Correct Answer: Hip flexion

Explanation:

Question 72:

Options:

MRI of the elbow and forearm
Bone scan
Electrodiagnostic studies
Radial tunnel injection
Radiographs of the wrist

Correct Answer: Radial tunnel injection

Explanation:

Question 73:

What is the primary mechanism of injury for the fracture shown in Figures 33a and 33b?

Options:

Hyperdorsiflexion
External rotation of the foot
Internal rotation of the foot
Adduction of the foot and ankle
Excessive eversion of the foot and ankle

Correct Answer: External rotation of the foot

Explanation:

Question 74:

Options:

Relief of symptoms with shoulder abduction (placing hand over the head)
Hypothenar atrophy
Reproduction of pain with hyperflexion and contralateral rotation of the head
Positive Tinel’s sign at the levator scapulae
Subluxable ulnar nerve at the cubital tunnel

Correct Answer: Relief of symptoms with shoulder abduction (placing hand over the head)

Explanation:

Question 75:

Options:

Observation, repeat radiographs, and reexamination in 6 weeks
A 14-day course of indomethacin
A 4-week course of indomethacin
Plan for a return to the operating room at 10 weeks for excision of the heterotopic bone
Arrange urgently for 800 centigrey of radiation to the soft tissues and areas of heterotopic bone around the hip, with shielding of the implants

Correct Answer: Observation, repeat radiographs, and reexamination in 6 weeks

Explanation:

DISCUSSION: The development of heterotopic bone occurs early after hip arthroplasty. The process begins within days after surgery; therefore, prophylactic treatment must be in the early postoperative period (preoperative radiation given within 24 hours of surgery, or postoperative radiation given within 72 hours of surgery, or nonsteroidal antiinflammatory drugs (NSAIDs) given postoperatively for 7 to 21 days - longer duration has not been shown to be of any additional benefit). At 6 weeks, prophylactic treatment with NS
AID
s or radiation is no longer effective. Surgery at 10 weeks would be premature because the patient is currently asymptomatic with regards to the heterotopic bone, and surgery prior to full maturation of the bone may increase the risk for more abundant recurrence of bone.
REFERENCES: Balboni TA, Gobezie R, Mamon HJ: Heterotopic ossification: Pathophysiology, clinical features, and the role of radiotherapy for prophylaxis. Int J Radiat Oncol Biol Phys 2006;65:1289-1299. Fransen M, Neal B: Non-steroidal anti-inflammatory drugs for preventing heterotopic bone formation after hip arthroplasty. Cochrane Database Syst Rev 2004;3:CD001160.
Neal BC, Rodgers A, Clark T, et al: A systematic survey of 13 randomized trials of non-steroidal antiinflammatory
drugs for the prevention of heterotopic bone formation after major hip surgery. Acta Orthop Scand 2000;71:122-128.

Question 76:

What zone of the physis is widened in rickets?

Options:

Reserve
Proliferative
Hypertrophic
Maturation
Primary spongiosa

Correct Answer: Hypertrophic

Explanation:

DISCUSSION: Rickets causes widening of the hypertrophic layer of the physis because of the failure of mineralization and vascular invasion. The other zones of the physis may be altered in other disease conditions but remain relatively unchanged in rickets.
REFERENCES: Hunziker EB, Schenk RK, Cruz-Orive LM: Quantitation of chondrocyte performance in growth-plate cartilage during longitudinal bone growth. J Bone Joint Surg Am 1987;69:162-173.
Iannotti JP: Growth plate physiology and pathology. Orthop Clin North Am 1990;21:1-17.

Question 77:

Options:

an immediate return to the operating room to explore the brachial plexus.
immediate electromyography and nerve conduction velocity studies.
MRI of the brachial plexus.
MRI of the cervical spine.
immobilization in a sling, followed by early passive range of motion.

Correct Answer: immobilization in a sling, followed by early passive range of motion.

Explanation:

Question 78:

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 79:

Which of the following factors increases the risk of sciatic nerve injury in primary total hip arthroplasty (THA)?

Options:

Male gender
Anterolateral approach
Posterior superior quadrant acetabular screw placement
Osteonecrosis
Developmental dysplasia of the hip

Correct Answer: Developmental dysplasia of the hip

Explanation:

DISCUSSION: Injury to the sciatic nerve is a relatively rare but serious complication of THA. Dissection of the sciatic nerve is not typically done during primary THA, although the nerve can be identified during the surgical approach. An anterolateral approach to THA would not necessarily be associated with any greater incidence of sciatic nerve injury than other approaches. Screw fixation for the acetabular component is often a matter of surgeon preference. Provided that the anatomic safe zones for screw fixation (posterior inferior and posterior superior) are recognized, injury to the sciatic nerve from acetabular screws can be minimized. Restoration of anatomic length is important in primary THA. Overlengthening can result in sciatic nerve palsy. Developmental dysplasia of the hip can lead to a congenitally shortened extremity with concomitant congenital shortening of the associated neurovascular structures. Overlengthening of the extremity during THA for developmental dysplasia of the hip can lead to sciatic palsy. Osteonecrosis is not an associated risk factor for sciatic nerve palsy.
REFERENCES: DeHart MM, Riley LH Jr: Nerve injuries in total hip arthroplasty. J Am Acad Orthop Surg 1999;7:101-111.
Anas P, Felix B: Evaluation and prevention of postoperative complications, in Neurologic Injury in Revision THA. New York, NY, Springer Verlag, 1999, pp 361-371.

Question 80:

Options:

Diffuse idiopathic skeletal hyperostosis
Ankylosing spondylitis
Ossification of the posterior longitudinal ligament
Rheumatoid arthritis
Degenerative cervical stenosis

Correct Answer: Ossification of the posterior longitudinal ligament

Explanation:

Question 81:

Which of the following occurs frequently after nonsurgical management of displaced intra-articular fractures of the calcaneus?

Options:

Return to normal function
Narrowing of the calcaneus
Lengthening of the calcaneus
Plantar flexion of the talus
Peroneal tendinitis

Correct Answer: Peroneal tendinitis

Explanation:

Question 82:

Four weeks after undergoing elective THA, an 80-year-old man is in the emergency department with sudden-onset right hip pain and an inability to bear weight after bending over in his garden.

Options:

Acute periprosthetic infection
Chronic periprosthetic infection
Joint dislocation
Periprosthetic fracture
Pseudotumor
Femoral nerve palsy
Sciatic nerve palsy
Aseptic prosthetic loosening

Correct Answer: Joint dislocation

Explanation:

Question 83:

In a patient who has undergone fusion with instrumentation from T4 to the sacrum for adult scoliosis, at which site is a pseudarthrosis most likely to be discovered?

Options:

T4-T5
T7-T8
L2-L3
L4-L5
L5-S1

Correct Answer: L5-S1

Explanation:

DISCUSSION: Although pseudarthrosis can be found anywhere within the spine that has been fused using long multisegmental fixation to the sacrum, it most commonly occurs at the lumbosacral junction. The thoracolumbar junction is another common site of potential pseudarthrosis. In this location, the anatomy changes from lumbar transverse processes to thoracic through the transition zone, and overlying instrumentation often makes it difficult to obtain enough sound bone on decorticated bone to achieve a successful fusion.
REFERENCES: Saer EH III, Winter RB, Lonstein JE: Long scoliosis fusion to the sacrum in adults with nonparalytic scoliosis: An improved method. Spine 1990;15;650-653.
Kostuik JP, Hall BB: Spinal fusions to the sacrum in adults with scoliosis. Spine
1983;8:489-500.
Balderston RA, Winter RB, Moe JH, et al: Fusion to the sacrum for nonparalytic scoliosis in the adult. Spine 1986;11:824-829.

Question 84:

A 42-year-old woman underwent an instrumented posterior spinal fusion at L3-S1 with transforaminal lumbar interbody fusion. She had an excellent

Options:

Observation
Oral antibiotics only
IV antibiotics only
Irrigation and debridement of the surgical site
Irrigation and debridement of the surgical site with hardware removal

Correct Answer: Irrigation and debridement of the surgical site

Explanation:

Question 85:

What defect in collagen synthesis is caused by a lack of vitamin C?

Options:

Impaired hydroxylation of proline
Failure of cleavage in procollagen
Defective binding sites for hydroxyproline
Failure to incorporate glycine into the helix
Diminished production of collagen through the rough endoplasmic reticulum

Correct Answer: Impaired hydroxylation of proline

Explanation:

Question 86:

Options:

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

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

Explanation:

Question 87:

Options:

Oral corticosteroid medication and changes in job activities
Soft-tissue interposition arthroplasty
Arthroscopic capsular release, loose body removal, and osteophyte decompression
Radial head arthroplasty
Total elbow arthroplasty

Correct Answer: Arthroscopic capsular release, loose body removal, and osteophyte decompression

Explanation:

Question 88:

A 25-year-old athlete presents with symptoms attributed to injury to ligament D in Figure A. Which of the following symptoms and signs is characteristic of this injury? Review Topic

Options:

Pain during late cocking and acceleration; milking maneuver.
Painful clicking during pushoff from armrests of a chair; milking maneuver.
Painful clicking during pushoff from armrests of a chair; lateral pivot shift.
Pain during late cocking and acceleration; lateral pivot shift.
Painful clicking during pushoff from armrests of a chair; moving valgus stress test.

Correct Answer: Pain during late cocking and acceleration; milking maneuver.

Explanation:

Question 89:

Options:

Growth arrest of the distal ulna
Growth arrest of the distal radius
Compartment syndrome
Radioulnar synostosis
Entrapment of the extensor pollicis longus (EPL) tendon

Correct Answer: Growth arrest of the distal ulna

Explanation:

Question 90:

Which of the following cardiac conditions is considered an absolute contraindication to vigorous exercise?

Options:

Hypertrophic cardiomyopathy (HCM)
Sclerosis of the aortic valve without stenosis
Mild mitral valve regurgitation
Left ventricular hypertrophy (LVH)
Functional murmurs

Correct Answer: Hypertrophic cardiomyopathy (HCM)

Explanation:

Question 91:

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

Options:

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

Correct Answer: RANK ligand (RANKL).

Explanation:

Question 92:

Options:

occupational therapy.
open reduction of the radial head and annular ligament reconstruction.
excision of the radial head.
ulnar osteotomy and closed reduction of the radial head.
ulnar osteotomy and open reduction of the radial head.

Correct Answer: ulnar osteotomy and open reduction of the radial head.

Explanation:

Question 93:

Options:

bone scan results returning to normal.
a decline in intensity on serial bone scans.
the serum levels of alkaline phosphatase measured over time.
the level of serum calcium-phosphorus product.
the time since injury and evidence of bone maturation on plain radiographs.

Correct Answer: the time since injury and evidence of bone maturation on plain radiographs.

Explanation:

Question 94:

During surgical treatment of the most common variation of distal femoral "Hoffa" fractures, which of the following orientations for screw fixation should be used?

Options:

Medial to lateral screw placement across lateral femoral condyle
Anterior to posterior screw placement across medial femoral condyle
Medial to lateral screw placement across medial femoral condle
Anterior to posterior screw placement across lateral femoral condyle
Anterior to posterior screw placement across intercondylar notch

Correct Answer: Medial to lateral screw placement across lateral femoral condyle

Explanation:

Question 95:

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

Options:

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

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

Explanation:

Question 96:

The flap shown in the clinical photograph seen in Figure 51 is based on what arterial supply?

Options:

Superficial circumflex iliac
Femoral lateral accessory
Inferior epigastric
Inferior inguinal
Lateral obturator

Correct Answer: Superficial circumflex iliac

Explanation:

Question 97:

Options:

free vascularized fibula.
calcium sulfate pellets.
corticocancellous autograft.
demineralized bone matrix. The patient developed a large bone defect after undergoing multiple débridements for an open fracture. The most appropriate graft in this setting is a vascularized bone graft. Considering the length of the defect, a free vascularized fibular graft would be a suitable graft. The indications for a vascularized bone graft include infection, inadequate vascularity of the surrounding tissues, bone defects larger than 6 centimeters, and previous failed bone grafts. The osteocytes survive in the vascularized graft, allowing primary bone healing and thereby limiting a loss of graft strength. In contrast, nonvascularized bone graft heals by creeping substitution with a loss of its initial strength. Calcium sulfate pellets and calcium phosphate cement are synthetic bone substitutes with osteoconductive properties. Their role in fracture healing is limited. Demineralized bone matrix is the matrix remaining after allograft undergoes decalcification processing. These products alone would not be optimal in the treatment of such a large bone defect.

Correct Answer: free vascularized fibula.

Explanation:

Question 98:

A 50-year-old patient who plays tennis sustained the deformity shown in Figure 27 following a high volley. Further diagnostic work-up should include

Options:

an electromyogram (EMG) of the upper extremity.
an ultrasound of the short head of the biceps.
an MRI scan of the rotator cuff.
a CT scan with contrast of the anterior labrum.
a subclavian venogram.

Correct Answer: an MRI scan of the rotator cuff.

Explanation:

Question 99:

A 43-year-old woman has had pain in the left hip for the past 2 months. A radiograph, CT scan, MRI scan, and biopsy specimens are shown in Figures 16a through 16e. What is the most likely diagnosis?

Options:

Osteosarcoma
Osteochondroma
Chondrosarcoma
Chordoma
Enchondroma

Correct Answer: Chondrosarcoma

Explanation:

Question 100:

What is the most important feature in choosing an outcome instrument to assess shoulder disorders?

Options:

Ease of use
Validity
Ability to use it by mail or phone so the subject is not required to return in person to measure the outcome
Inclusion of radiographic assessment at follow-up
Scoring that is on a 100-point scale so that it can be compared with other instruments

Correct Answer: Validity

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

Orthopedic Board Review MCQs: Arthroplasty, Trauma & Infection | Part 146

Key Takeaway

About This Board Review Set

How to Use the Interactive Quiz

Topics Covered in Part 146

Sample Questions from This Set

Why Active MCQ Practice Works

Chapter Index