AAOS & ABOS Orthopedic MCQs (Set 1): Shoulder Instability, Rotator Cuff, Proximal Humerus Fractures | 2026 Board Review

Key Takeaway
This high-yield question set for 2026 AAOS/ABOS board review focuses on upper extremity orthopedics. It covers the diagnosis and management of shoulder instability, various rotator cuff pathologies, and the surgical principles for proximal humerus fractures, aiding in comprehensive exam preparation.
Comprehensive 100-Question Exam
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Question 1
A collegiate football player who sustained an injury to his neck has significant neck pain and weakness in his extremities. Following immobilization, which of the following steps should be taken prior to transport?
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Question 2
The pathophysiology of a claw toe deformity includes muscular imbalance caused by which of the following relatively strong structures?

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Question 3
A newborn girl with an isolated unilateral dislocatable hip is placed in a Pavlik harness with the hips flexed 100 degrees and at resting abduction. Figure 23 shows an ultrasound obtained 2 weeks later. What is the next step in management?

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Question 4
What complication is frequently associated with the Weil lesser metatarsal osteotomy (distal, oblique) in the treatment of claw toe deformities?
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Question 5
Figure 42 is a transverse MRI scan of the left shoulder. The arrow points to which of the following structures?

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Question 6
Which of the following patient factors is associated with recurrent radicular pain following lumbar diskectomy for sciatica?
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Question 7High Yield
A 24-year-old woman has a spleen laceration and hypotension. Radiographs reveal a pulmonary contusion and a displaced mid-diaphyseal fracture of the femur. The trauma surgeon clears her for stabilization of the femoral fracture. What technique will offer the least potential for initial complications?

Explanation
Question 8High Yield
An 8-year-old boy with severe hemophilia A (factor VIII) and no inhibitor is averaging eight transfusions per month for bleeding into the right ankle. Examination shows synovial hypertrophy; range of motion consists of 0 degrees of dorsiflexion and 20 degrees of plantar flexion. The patient's knees, elbows, and left ankle have no restriction of motion. Standing radiographs of the right ankle are shown in Figure 18. Management should consist of

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Question 9 High Yield
A 30-year-old man has had a 3-day history of severe, incapacitating lower back pain without radiation. He reports improvement with rest. He denies any history of trauma, has no constitutional symptoms, and his neurologic examination is normal. What is the best course of action?
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Question 10
A patient has a displaced complex intra-articular distal humeral fracture. What factor is considered most important when deciding on what surgical approach to use?

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Question 11
What are the five most common tumors that metastasize to bone?
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Question 12High Yield
When compared with fresh-frozen bone allograft, freeze-dried bone allograft (FDBA) is characterized by
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Question 13
A 31-year-old woman has a history of a painful ankle that has failed to respond to conservative management. She has associated night pain that is relieved with nonsteroidal anti-inflammatory drugs. MRI and technetium Tc 99m scans are consistent with an osteoid osteoma. Management should now consist of
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Question 14
Figures 19a and 19b show the AP and lateral radiographs of an 18-year-old man who has had knee pain for 3 months. Figure 19c shows a histopathologic photomicrograph of the biopsy specimen. Which of the following factors is most likely to affect his survival?

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Question 15High Yield
Which of the following malignant tumors most commonly contains soft-tissue calcifications seen on radiographs or CT?

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Question 16
Figures 3a and 3b show the MRI scans of a patient with neck pain. What is the most likely diagnosis?

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Question 17High Yield
Figure 26 shows the clinical photograph of a patient who has developed a residual limb ulcer following a traumatic transtibial amputation 2 years ago. What is the preferred treatment to resolve the ulcer?

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Question 18High Yield
A patient with degenerative osteoarthritis of the sternoclavicular (SC) joint reports constant pain, discomfort, and marked prominence and instability of the SC joint following medial clavicle resection. Which of the following procedures is most likely to produce these signs and symptoms?
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Question 19
A 51-year-old man sustained an open fracture of his tibia in Korea 42 years ago. An infection developed and it was resolved with surgical treatment. For the past 6 months, an ulcer with mild drainage has developed over the medial tibia. The ulcer is small and there is minimal erythema at the ulcer site. A radiograph and MRI scan are shown in Figures 43a and Figure 43b. Initial cultures show Staphylococcus aureus susceptible to the most appropriate antibiotics. Laboratory studies show an erythrocyte sedimentation rate of 70 mm/h. What is the most appropriate surgical treatment at this time?

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Question 20
The vascularity of the digital flexor tendons is significantly richer in what cross-sectional region?
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Question 21High Yield
A 22-year-old patient sustained a jamming injury to the right little finger. The lateral radiograph shown in Figure 18 reveals comminution of the base of the middle phalanx, with palmar and dorsal metaphyseal cortical involvement. The articular surface also is disrupted. Management should consist of

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Question 22
Figure 33 shows the radiograph of a 28-year-old avid golfer who has chronic right wrist pain. Management should consist of

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Question 23High Yield
A 56-year-old man sustained a nondisplaced extra-articular fracture of the proximal aspect of the third metatarsal after dropping a heavy object on his left foot. Management should consist of
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Question 24
An 18-year-old girl with quadriplegic cerebral palsy underwent posterior spinal fusion from T2 to the pelvis 3 weeks ago. She now has a low-grade fever and mild midline erythema in a 1-cm area from which there is slight clear yellowish drainage. What is the next most appropriate step in management?

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Question 25High Yield
A 32-year-old woman sustained an injury to her left upper extremity in a motor vehicle accident. Examination reveals a 2-cm wound in the mid portion of the dorsal surface of the upper arm and deformities at the elbow and forearm; there are no other injuries. Her vital signs are stable, and she has a base deficit of minus 1 and a lactate level of less than 2. Radiographs are shown in Figures 9a and 9b. In addition to urgent debridement of the humeral shaft fracture, management should include

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Question 26High Yield
A 39-year-old woman fell onto her flexed elbow and sustained a comminuted displaced radial head and neck fracture. Radiographs confirm concentric reduction of the ulnohumeral joint. Examination reveals pain with compression of the radius and ulna at the wrist. What is the best treatment for the radial head fracture?
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Question 27
What is the most common result if the acetabulum is rotated too far anteriorly during a periacetabular osteotomy?
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Question 28High Yield
A 21-year-old soccer player reports pain and is unable to straighten his knee following an acute injury during a game. He is unable to continue to play. An MRI scan is shown in Figure 3. What is the next most appropriate step in management?

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Question 29High Yield
A 16-year-old snowboarder has significant pain and is still unable to bear weight after sustaining a lateral ankle injury in a fall 1 week ago. Examination reveals swelling and tenderness in the sinus tarsi. AP, lateral, and mortise radiographs of the ankle are unremarkable. Management should consist of
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Question 30
A 14-year-old boy reports progressive right wrist pain. Radiographs are shown in Figure 3a, and a photomicrograph is shown in Figure 3b. What is the most likely diagnosis?

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Question 31
The strongest biomechanical construct for open reduction and internal fixation of a talar neck fracture uses what interval and entry point?
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Question 32
A 60-year-old woman has activity-related hip pain after undergoing arthroplasty 5 years ago. She has severe Parkinsonism and denies fevers or chills. Radiographs are shown in Figures 45a and 45b. What is the most likely cause of her pain?

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Question 33High Yield
Figure 11 shows the radiograph of an 18-year-old soccer player who reports recurrent lateral foot pain after sustaining an inversion injury. History reveals that 6 months ago he had been treated in a non-weight-bearing cast for a fifth metatarsal fracture. Management should consist of

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Question 34
A patient reports hyperesthesia over the base of the thenar eminence following volar locked plating of a distal radius fracture. A standard volar approach of Henry was used. What is the most likely cause of the hyperesthesia?

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Question 35
What percent of the adult human meniscus is vascularized?
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Question 36 High Yield
A 21-year-old patient has had pain and a marked decrease in active and passive shoulder motion after having had a seizure 2 months ago as the result of alcohol abuse. Current AP and axillary radiographs and a CT scan are shown in Figures 26a through 26c. Management should consist of

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Question 37 High Yield
The specificity of intraoperative frozen sections obtained for the evaluation of infected total hip arthroplasty may be improved by
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Question 38
Within the menisci, the majority of the large collagen fiber bundles are oriented in what configuration?
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Question 39
A newborn girl is referred for evaluation of suspected hip instability. What information from her history would place her in the highest risk category?
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Question 40High Yield
In surgically treating hand and finger infections in patients with diabetes mellitus, what factor is associated with higher amputation rates?
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Question 41
What bilateral surgical intervention is considered inappropriate based on the findings shown in the radiograph in Figure 52?

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Question 42High Yield
What is the most likely consequence of a vertebral compression fracture associated with osteoporosis?
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Question 43High Yield
A 60-year-old woman with a history of breast cancer has progressive paraparesis. The MRI scan is shown in Figure 28. What form of management is most likely to restore or maintain ambulation?

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Question 44
Which of the following properties apply to the human meniscus when compared with articular cartilage?

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Question 45 High Yield
During reconstruction of insertional gaps of a chronic Achilles tendon rupture, what tendon provides the most direct route of transfer?

Detailed Explanation
Question 46
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?
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Question 47
A 46-year-old woman has bilateral groin pain, with more severe pain on the left side than on the right side. Figures 44a and 44b show a radiograph and a T1-weighted MRI scan. What is the most likely diagnosis?

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Question 48
What mechanism contributes to strength gains during conditioning of the preadolescent athlete?
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Question 49
In the spine, osteoblastomas usually originate in the

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Question 50High Yield
Figure 6 shows the clinical photographs of a newborn who underwent a colostomy for an imperforate anus. Examination shows extended knees, flexed hips, and equinovarus feet. Dimpling is noted over the buttocks. Patients with these findings differ from patients with myelodysplasia in that they

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Question 51
A patient with refractory long head biceps pain in the shoulder undergoes biceps tenotomy. The patient is concerned about possible postoperative deformity and loss of supination strength. Which of the following techniques provides the strongest initial fixation to prevent distal migration?
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Question 52
A 52-year-old woman reports nagging shoulder pain that has been present for months and is slowly progressive in nature. The patient also reports nocturnal pain and notes that the pain is not activity related. Figures 27a and 27b show the radiograph and bone scan, and Figures 27c through 27e show T1-weighted, T2-weighted, and gadolinium MRI scans, respectively. Based on these findings, what is the most likely diagnosis?

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Question 53 High Yield
Figures 46a through 46e show the radiographs of a 22-year-old man who injured his wrist in a motorcycle accident. He has no other injuries. What is the best course of action?

Detailed Explanation
Question 54High Yield
A 7-year-old patient has had a painless limp for several months. Examination reveals pain and spasm with internal rotation, and abduction is limited to 10 degrees on the involved side. Management consists of 1 week of bed rest and traction, followed by an arthrogram. A maximum abduction/internal rotation view is shown in Figure 40a, and abduction and adduction views are shown in Figures 40b and 40c. The studies are most consistent with

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Question 55 High Yield
A 47-year-old patient has had persistent pain and weakness after undergoing a reamed intramedullary nailing for a midshaft humerus fracture 8 months ago. There is no evidence of infection. Radiographs are shown in Figures 19a and 19b. Management should consist of

Detailed Explanation
Question 56
A 32-year-old man notes increasing back pain and progressive paraparesis over the past few weeks. He is febrile, and laboratory studies show a WBC of 12,500/mm3. MRI scans are shown in Figures 6a and 6b. Management should consist of

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Question 57
What is the most important feature in choosing an outcome instrument to assess shoulder disorders?
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Question 58High Yield
What is one of the principle concerns when a fracture such as the one seen in Figure 18 is encountered?

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Question 59
A 30-year-old man who underwent an anterior lumbar diskectomy and fusion at L4-5 and L5-S1 through an anterior retroperitoneal approach 1 month ago now reports he is unable to obtain and maintain an erection. The most likely cause of this condition is
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Question 60
A 75-year-old woman began a walking program 2 months after undergoing right total knee arthroplasty. She had to stop the program after 4 weeks because of hindfoot pain and ankle swelling. Radiographs are shown in Figures 42a and 42b. What is the most likely diagnosis?

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Question 61
A 16-year-old boy with osteochondritis dissecans of the capitellum has intermittent symptoms of catching and locking. Examination is unremarkable. Radiographs reveal a loose body anteriorly with a diameter of 10 mm. To remove the loose body, elbow arthroscopy is being considered. Which of the following procedures would minimize the risk of neurovascular complication during the procedure?
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Question 62
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?

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Question 63
A 21-year-old professional baseball player has had painful catching and stiffness in his dominant right elbow for the past year. Examination reveals a flexion contracture of 2 degrees and mild pain with full elbow flexion. Radiographs are shown in Figures 33a and 33b. The most effective management should consist of

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Question 64High Yield
Which of the following is a recognized consequence of hip fusion?

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Question 65High Yield
A 24-year-old woman has a spleen laceration and hypotension. Radiographs reveal a pulmonary contusion and a displaced mid-diaphyseal fracture of the femur. The trauma surgeon clears her for stabilization of the femoral fracture. What technique will offer the least potential for initial complications?

Explanation
Question 66High Yield
Figures 36a and 36b show the radiographs of a 48-year-old woman who smokes cigarettes and sustained a segmental femoral shaft fracture in a motor vehicle accident 9 months ago. Initial management consisted of stabilization with a reamed statically locked intramedullary nail. She now reports lower leg pain that increases with activity. In addition to advising the patient to quit smoking, management should include

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Question 67
Figure 7 shows the radiograph of an 18-year-old hockey player who sustained a shoulder injury during a fall into the side boards. Examination reveals a significant prominence at the acromioclavicular joint. Management should consist of

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Question 68High Yield
What is the most common complication following arthroscopic capsular release in a patient with adhesive capsulitis of the shoulder?

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Question 69 High Yield
Which of the following statements best describes why the ulnar nerve is most prone to neuropathy at the elbow?

Detailed Explanation
Question 70
A 13-year-old patient has foot drop and lateral knee pain. AP and lateral radiographs and an MRI scan are shown in Figures 49a through 49c. A biopsy specimen is shown in Figure 49d. What is the preferred method of treatment?

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Question 71
What is the most common organism found following a nail puncture wound through tennis shoes in a host without immunocompromise?
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Question 72
A 17-year-old girl with Charcot-Marie-Tooth disease reports the development of progressive instability when walking on uneven surfaces. Her involved heel is positioned in varus when viewed from behind. Examination reveals that she walks on the outer border of the involved foot. She has full passive motion of the ankle and hindfoot joints. She is able to dorsiflex the ankle against resistance. The heel varus fully corrects with the Coleman block test. Standing radiographs reveal a cavus deformity with valgus of the forefoot. She would like to avoid using an ankle-foot orthosis. What is the best surgical option?

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Question 73
Figure 24 shows the sitting AP and lateral spinal radiographs of a nonambulatory 12½-year-old boy with Duchenne muscular dystrophy who is being evaluated for scoliosis. The lumbar curve from T12 to L5 measures 36 degrees, and the thoracic curve from T3 to T12 measures 24 degrees on the AP radiograph. He has 5 degrees of pelvic obliquity. His forced vital capacity is 45% of predicted for height and weight. What is the most appropriate treatment for the spinal deformity?

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Question 74
What is the most common diagnosis in a patient older than age 40 years with a destructive bony lesion?
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Question 75
An 8-year-old girl has had a painless enlarging mass of insidious onset in the left thigh for the past 3 weeks. Her mother denies any history of trauma, fever, or disease. Examination reveals a nontender, mobile mass in the left medial thigh. Her gait is normal. Figures 25a through 25d show the frog-lateral radiograph, the axial and coronal T1-weighted MRI scans, and the axial T2-weighted MRI scan. Biopsy results reveal a nonrhabdomyosarcoma soft-tissue sarcoma. The most appropriate treatment should consist of

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Question 76
A 40-year-old right hand-dominant construction worker has had a 6-month history of aching left shoulder pain that is worse after working a long day. Examination reveals limited range of motion and good strength when compared to his asymptomatic right arm. He has not had any orthopaedic intervention to date. Radiographs are shown in Figures 43a and 43b. What is the most appropriate treatment?

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Question 77High Yield
Figures 36a and 36b show the radiographs of a 3-year old child who has a congenital upper extremity deformity. Which of the following features would be a major contraindication to a centralization procedure?

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Question 78
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?

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Question 79High Yield
The MRI scan shown in Figure 24 reveals a right-sided herniated nucleus pulposus at L4-5 in a patient with pain in the right leg. Administration of a caudal epidural steroid injection provides immediate relief. Over the next week he notes generalized weakness of the lower extremities and has one episode of urinary incontinence. What is the next most appropriate step in management?

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Question 80High Yield
Figure 10 shows the MRI scan of a 56-year-old woman with metastatic breast cancer who now reports progressive paraparesis. Her general health remains good. Treatment should consist of

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Question 81
Figure 16 shows the clinical photograph of a 3-month-old infant with a foot deformity that has been nonprogressive since birth. Examination reveals that the deformity corrects actively and with passive manipulation. There is no associated equinus. Management should consist of

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Question 82 High Yield
Figures 52a and 52b show the radiographs of a left proximal femoral lesion noted serendipitously following minor trauma to the left hip. The patient has no thigh pain and is fully active without limitation. What is the most likely diagnosis of this bony lesion?

Detailed Explanation
Question 83High Yield
A 37-year-old woman has had intermittent paresthesias and numbness in the plantar foot for the past 6 months. She reports that the symptoms are worse with activity, and the paresthesias are beginning to awaken her at night. MRI scans are shown in Figures 6a and 6b. What is the most likely diagnosis?

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Question 84High Yield
When compared to traditional open repair through a posterior incision, percutaneous Achilles tendon repair clearly results in a reduction of what complication?
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Question 85
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
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Question 86
Which of the following is considered a reasonable goal for arthroplasty surgery in rotator cuff arthropathy?
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Question 87
Which of the following is considered an important factor in improved cemented femoral stem survivorship?
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Question 88High Yield
Which of the following factors is most commonly associated with mechanical failure of a cemented total hip arthroplasty?

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Question 89
Figures 16a and 16b show the radiographs of an otherwise healthy 3 1/2-year-old boy who has an isolated deformity of the left leg. Definitive primary treatment of this condition should consist of

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Question 90
The parents of a 13-year-old boy with Down syndrome report that he has an increasing limp and decreased endurance with activities. Lateral flexion-extension radiographs of the cervical spine show no evidence of instability. Examination reveals a right Trendelenburg limp and an obvious limb-length discrepancy. Hip motion is symmetric except for some decreased abduction on the right side. A standing AP radiograph is shown in Figure 20. Management should consist of

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Question 91 High Yield
A 17-year-old boy underwent open reduction and internal fixation of a navicular fracture 5 days ago. A follow-up examination now reveals a tensely swollen foot with erythema and multiple skin bullae. The patient is febrile and has marked pain with palpation of the entire forefoot and hindfoot. What is the next step in management?
Detailed Explanation
Question 92High Yield
Figures 21a through 21c show the MRI scans of a 21-year-old football player who sustained a valgus knee injury while changing direction. Examination reveals swelling and tenderness along the medial aspect of the knee. There is a positive Lachman test, 3+ valgus laxity at 30 degrees, and 1+ valgus laxity at 0 degrees extension. The anterior drawer test is increased with the tibia in external rotation. The increase in the anterior drawer test with the tibia in external rotation is most likely the result of

Explanation
Question 93 High Yield
A 25-year-old man is brought to the emergency department following a motor vehicle accident. Extrication time was 2 hours, and in the field he had a systolic blood pressure by palpation of 90 mm Hg. Intravenous therapy was started, and on arrival in the emergency department he has a systolic blood pressure of 90 mm Hg with a pulse rate of 130. Examination reveals a flail chest and a femoral diaphyseal fracture. Ultrasound of the abdomen is positive. The trauma surgeons take him to the operating room for an exploratory laparotomy. At the conclusion of the procedure, he has a systolic pressure of 100 mm Hg with a pulse rate of 110. Oxygen saturation is 90% on 100% oxygen, and he has a temperature of 95.0 degrees F (35 degrees C). What is the recommended treatment of the femoral fracture at this time?
Detailed Explanation
Question 94 High Yield
A 14-year-old boy reports a 4-month history of increasing backache with difficulty walking long distances. His parents state that he walks with his knees slightly flexed and is unable to bend forward and get his hands to his knees. He denies numbness, tingling, and weakness in his legs and denies loss of bladder and bowel control. A lateral radiograph of the lumbosacral spine is shown in Figure 18. What is the best surgical management for this condition?

Detailed Explanation
Question 95 High Yield
What type of injury is considered the major mechanism of cervical fracture, dislocation, and quadriplegia in contact sports and diving?

Detailed Explanation
Question 96 High Yield
A 67-year-old man is requesting revision surgery because of continued pain in the knee after undergoing a total knee replacement 2 years ago. Examination reveals that the knee is not warm, the incision is well-healed, and the skin has normal coloration and hair formation. No varus or valgus instability is noted, and knee range of motion is 5 degrees to 100 degrees. Laboratory studies show an erythrocyte sedimentation rate of 15 mm/h and a WBC of 5,000/mm3. Aspiration of the knee reveals clear fluid that shows no growth on culture. Radiographs reveal an appropriately positioned cruciate-retaining cemented total knee arthroplasty that is well-fixed. What is the probability that the patient's pain will be improved with revision surgery?

Detailed Explanation
Question 97
Figure 27 shows the AP radiograph of a patient who has late instability. The problem most likely occurred as a result of

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Question 98 High Yield
When converting the knee shown in Figure 20 to a total knee arthroplasty, satisfactory outcome can be expected in what percent of patients?

Detailed Explanation
Question 99
A 7-year-old boy sustains an acute injury to the distal radial metaphysis, along with a completely displaced Salter-Harris type I fracture of the ulnar physis, as shown by the arrows in Figure 12. After satisfactory reduction of both injuries, what is the major concern?

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Question 100High Yield
Which of the following drawbacks is associated with the Ganz periacetabular osteotomy?
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