Orthopedic Surgery Mock Exam - Set E9DF28

A 13-year-old obese boy presents with a 3-month history of vague left knee pain and a limp. Physical examination demonstrates an obligate external rotation of the left hip during flexion. Radiographs demonstrate a posterior and inferior displacement of the proximal femoral epiphysis. Through which physeal zone does the primary failure occur in this condition?

A 32-year-old man sustains a closed fracture of the distal third of his humeral shaft, presenting with an inability to actively extend his wrist and digits. He undergoes open reduction and internal fixation using a posterior triceps-splitting approach. Which of the following accurately describes the relationship of the radial nerve to the humerus and intermuscular septum at the level of the distal third of the humeral shaft?

A 15-year-old boy presents with progressive, severe night pain in his distal thigh over 2 months. Radiographs reveal a mixed lytic and sclerotic lesion in the distal femoral metaphysis with a robust periosteal reaction demonstrating a 'sunburst' pattern. Biopsy confirms high-grade intramedullary osteosarcoma. Which of the following genetic mutations is most frequently implicated in the pathogenesis of this tumor?

A 22-year-old female soccer player undergoes primary anterior cruciate ligament (ACL) reconstruction using a bone-patellar tendon-bone autograft. Postoperatively, she experiences loss of terminal extension and anterior knee pain. An MRI indicates graft impingement against the intercondylar roof. Which of the following technical errors during tunnel preparation is the most common cause of this specific impingement pattern?

A 60-year-old man with poorly controlled diabetes mellitus presents with worsening back pain and low-grade fevers for 1 week. Over the past 24 hours, he developed progressive bilateral leg weakness and urinary retention. MRI reveals a massive ventral fluid collection from L2 to L4 causing severe compression of the cauda equina, consistent with a spinal epidural abscess. What is the most common causative organism isolated in this condition?

A 28-year-old professional football player sustains an axial load to his plantarflexed foot. Weight-bearing radiographs demonstrate a 4 mm diastasis between the base of the first and second metatarsals. He is diagnosed with a Lisfranc injury. Which of the following ligaments is primarily disrupted in this classic injury pattern?

A 24-year-old carpenter sustains a deep laceration to the volar aspect of his right index finger exactly at the level of the proximal interphalangeal (PIP) joint flexion crease. Examination shows absent active flexion at both the PIP and DIP joints. During surgical exploration, complete lacerations of the FDP and FDS tendons are identified. In which flexor tendon zone is this injury located?

A 35-year-old woman undergoes open reduction and internal fixation of a diaphyseal radial fracture using a dynamically compressed plate, achieving absolute fracture stability and anatomical reduction. Which of the following best describes the primary mechanism of bone healing expected in this specific environment?

A 55-year-old highly active man is scheduled for a total hip arthroplasty (THA). The surgeon considers utilizing a ceramic-on-ceramic bearing surface to maximize longevity. Which of the following is the most notable disadvantage or complication specific to a ceramic-on-ceramic bearing compared to ceramic-on-highly cross-linked polyethylene?

A hemodynamically unstable 42-year-old male is brought to the trauma bay after a motorcycle crash. Pelvic radiographs demonstrate an APC-III pelvic ring injury ('open book' pelvis). A pelvic binder is immediately applied by the trauma team. Which of the following statements regarding the application and function of a pelvic binder is most accurate?

A 6-year-old boy presents with a painless limp of 3 months' duration. His mother notes restricted hip motion, particularly in abduction and internal rotation. Radiographs reveal sclerosis, flattening, and early fragmentation of the proximal femoral epiphysis. In the natural history of Legg-Calvé-Perthes disease, which of the following represents the correct sequence of radiographic stages?

A 20-year-old collegiate quarterback sustains a traumatic anterior shoulder dislocation. Post-reduction MRI demonstrates an anterior-inferior labral tear that is displaced medially and rolled down the glenoid neck, still attached to an intact but stripped anterior periosteal sleeve. Which of the following eponymous terms best describes this specific soft-tissue lesion?

A 32-year-old woman complains of left knee pain. Radiographs show an eccentric, purely lytic lesion in the distal femoral epiphysis extending to the subchondral bone, without a sclerotic margin. Biopsy reveals multinucleated giant cells interspersed among mononuclear stromal cells. For recurrent or surgically unsalvageable cases of this specific tumor, which of the following is the most appropriate targeted medical therapy?

A 45-year-old woman presents with severe numbness and tingling in her thumb, index, and middle fingers, confirming a diagnosis of severe carpal tunnel syndrome. She is scheduled for an open carpal tunnel release. Which of the following anatomical structures is NOT contained within the true carpal tunnel?

A 58-year-old man with long-standing diabetic peripheral neuropathy presents with a swollen, erythematous, and warm right foot without ulcerations. He reports minimal pain but his midfoot arch has collapsed over the past month. Radiographs demonstrate fragmentation, periarticular debris, and subluxation at the tarsometatarsal joints. Which of the following is the most appropriate initial management for the acute phase of this condition?

A 52-year-old man presents with sharp neck pain radiating down his right arm. Physical examination reveals weakness in active elbow extension and wrist flexion. He also reports decreased sensation isolated to the dorsum of his middle finger. Which cervical nerve root is most likely compressed?

In total joint arthroplasty, ultra-high-molecular-weight polyethylene (UHMWPE) is subjected to gamma irradiation to induce extensive cross-linking. While this process significantly improves wear resistance, what is the primary mechanical disadvantage introduced by highly cross-linking the polyethylene?

During a primary total knee arthroplasty (TKA), the surgeon evaluates the flexion and extension gaps. Utilizing spacer blocks, the surgeon notes that the extension gap is symmetric and perfectly balanced, but the flexion gap is excessively tight. Assuming an anterior referencing sizing guide was used, which of the following surgical adjustments is the most appropriate next step to balance the knee?

A 27-year-old man sustains a closed midshaft tibia fracture treated with intramedullary nailing. Six hours postoperatively, he develops severe, out-of-proportion leg pain and severe pain with passive stretch of his toes. Compartment pressure monitoring reveals an anterior compartment pressure of 45 mmHg. The decision is made to perform a standard four-compartment fasciotomy of the leg via a dual-incision technique. During the lateral incision, which anatomical structure is utilized as the key landmark to identify and separate the anterior and lateral compartments?

A 22-year-old man falls onto an outstretched hand and presents with marked anatomic snuffbox tenderness. Initial radiographs are negative, but an MRI obtained 3 days later confirms a nondisplaced fracture traversing the proximal pole of the scaphoid. What is the primary anatomical reason this specific fracture pattern is highly predisposed to avascular necrosis and nonunion?

What primary manufacturing process decreases the wear rate of highly cross-linked polyethylene (HXLPE) compared to conventional polyethylene in total hip arthroplasty?

A 4-month-old infant is treated with a Pavlik harness for developmental dysplasia of the hip. At a follow-up visit, the infant is noted to have decreased active extension of the knee on the treated side. Which of the following positioning errors is the most likely cause of this complication?

A 35-year-old male presents after a high-speed motorcycle crash. Pelvic radiographs reveal symphysis pubis widening of 3.5 cm and widening of the anterior sacroiliac joints bilaterally, with intact posterior SI ligaments. What is the most common anatomic source of life-threatening hemorrhage in this specific injury pattern?

A 22-year-old presents with radial-sided wrist pain after a fall. A scaphoid waist fracture is diagnosed. The proximal pole of the scaphoid is at high risk for avascular necrosis due to its tenuous blood supply. Which of the following best describes the predominant arterial supply to the scaphoid?

During an anterior cruciate ligament (ACL) reconstruction, the surgeon places the femoral tunnel excessively anterior to the anatomic footprint. What is the most likely biomechanical consequence of this malpositioning?

A 14-year-old boy presents with severe, unrelenting thigh pain and low-grade fevers. Radiographs show a permeative diaphyseal lesion with an 'onion-skin' periosteal reaction. Biopsy reveals sheets of uniform small round blue cells. Which chromosomal translocation is most characteristic of this condition?

A 65-year-old man with cervical spondylotic myelopathy exhibits a positive Hoffmann sign on physical examination. The presence of this physical sign indicates abnormal function primarily involving which of the following descending pathways?

A 55-year-old poorly controlled diabetic patient presents with a warm, swollen, and erythematous foot. Initial radiographs reveal fragmentation of the midfoot bones, periarticular debris, and early joint subluxation, but no signs of consolidation. According to the Eichenholtz classification of Charcot arthropathy, which stage does this represent?

Distraction osteogenesis, as pioneered by Ilizarov, is a powerful technique for limb lengthening and deformity correction. The formation of new bone across the distraction gap primarily relies on which biological process?

A 13-year-old boy with a BMI of 32 presents with right knee pain and an antalgic limp. Examination reveals obligatory external rotation with hip flexion. He is diagnosed with a slipped capital femoral epiphysis (SCFE). Which of the following is considered an indication for prophylactic pinning of the contralateral asymptomatic hip?

A 28-year-old male sustains a high-energy closed tibial shaft fracture. Two hours post-admission, he complains of worsening, unrelenting pain out of proportion to his injury. His diastolic blood pressure is 80 mmHg and mean arterial pressure is 95 mmHg. Compartment pressures are measured. What measurement threshold is the most widely accepted absolute indication for a four-compartment fasciotomy?

In the surgical anatomy of the hand, Flexor Tendon Zone II (historically referred to as 'no man's land') is defined by specific anatomical landmarks. Which of the following best describes the boundaries of Zone II?

During arthroscopic management of anterior shoulder instability, a 'remplissage' procedure is occasionally indicated for a patient with an engaging Hill-Sachs lesion. This technique involves tenodesis of the posterior joint capsule and which of the following structures into the humeral defect?

To avoid galvanic corrosion in orthopedic implants, dissimilar metals should generally not be in physical contact. However, combining a cobalt-chromium femoral head with a titanium alloy femoral stem is clinically common and highly successful. What is the primary electrochemical reason this specific modular combination is acceptable?

During a primary total knee arthroplasty utilizing a measured resection technique, trial components are placed. Examination of the joint reveals that the knee is well-balanced and symmetric in 90 degrees of flexion, but it is excessively tight in full extension. Which of the following is the most appropriate next step to balance the knee?

A 68-year-old woman complains of bilateral buttock, thigh, and calf pain that occurs after walking three blocks. The pain is rapidly relieved when she sits down or leans forward over a shopping cart. Physical examination reveals normal pedal pulses. What is the primary anatomical explanation for the relief she experiences when leaning forward?

A 45-year-old woman requires open reduction and internal fixation for a volar Barton's fracture of the distal radius. The surgeon utilizes the standard volar Henry approach. Distally, this approach develops an internervous plane between which two structures?

A 50-year-old male undergoes biopsy of a painful, enlarging proximal humerus mass, confirming the diagnosis of a conventional Grade II chondrosarcoma. Staging reveals no evidence of metastasis. What is the standard primary treatment modality for this lesion?

A 6-year-old boy sustains a completely displaced (Gartland Type III) supracondylar humerus fracture. Radiographs reveal that the distal fracture fragment is displaced posterolaterally. Given this specific displacement pattern, which nerve is at the highest risk of injury?

When comparing operative versus nonoperative management for acute Achilles tendon ruptures using modern functional rehabilitation protocols (early weight-bearing and motion), which of the following statements best reflects the consensus of recent high-level literature?