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2018 Graduate Professional Course Exam Questions: Pass with Confidence

Comprehensive Orthopedic Board Prep: MCQ Practice Engine & Exam Simulation

23 Apr 2026 80 min read 95 Views
Illustration of e bp mmhgp - Dr. Mohammed Hutaif

Key Takeaway

Effective Orthopedic Board preparation utilizes an interactive MCQ engine offering high-yield questions in both study and timed exam modes. This approach allows users to practice specific topics, simulate test conditions, track progress, and review detailed explanations, ensuring comprehensive understanding and improved retention vital for successful board certification.

Comprehensive Exam


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Question 1

A 35-year-old male presents with severe pelvic pain after a high-energy motor vehicle collision. He is hypotensive (BP 80/50 mmHg) and tachycardic (HR 120 bpm). Physical examination reveals a distended abdomen, perineal ecchymosis, and an open book pelvic injury evident on AP pelvis X-ray. Initial management should prioritize which of the following?





Explanation

In a hemodynamically unstable patient with an open book pelvic fracture, immediate resuscitation with fluids and blood products is paramount. Application of a pelvic binder or sheet is crucial to reduce the pelvic volume and tamponade hemorrhage, thereby stabilizing the patient. While external fixation, angiography, laparotomy, and urethral evaluation are often necessary in subsequent steps, they follow initial hemodynamic stabilization.

Question 2

A 68-year-old male presents with a 6-month history of bilateral lower extremity pain, numbness, and weakness, exacerbated by walking and relieved by sitting or leaning forward. His MRI shows severe lumbar canal stenosis at L4-L5 with degenerative spondylolisthesis. Neurological examination reveals mild weakness in bilateral quadriceps (4/5) and diminished patellar reflexes. Which of the following is the most appropriate initial management strategy?





Explanation

The patient exhibits classic symptoms of lumbar spinal stenosis with neurogenic claudication. While surgical intervention (decompression, often with fusion for instability like degenerative spondylolisthesis) is definitive for severe, refractory symptoms, conservative management is typically the first line. This includes physical therapy (flexion-based exercises often helpful), epidural steroid injections (for short-term pain relief), NSAIDs, and neuropathic pain medications like gabapentin. Urgent surgery is reserved for progressive neurological deficit or cauda equina syndrome. Myelogram is largely supplanted by MRI for diagnosis.

Question 3

A 72-year-old female undergoes a cemented total hip arthroplasty for osteoarthritis. Post-operatively, she develops sudden onset dyspnea, hypoxemia, and a petechial rash. Which of the following is the most likely diagnosis?





Explanation

The classic triad of symptoms (respiratory distress, neurological deficits, and petechial rash) following a long bone fracture or arthroplasty (especially cemented, which can increase intramedullary pressure, pushing marrow contents into the circulation) strongly suggests fat embolism syndrome. Pulmonary embolism often presents with dyspnea and hypoxemia but typically lacks the petechial rash and prominent neurological symptoms. Other options are less likely given the specific symptom constellation and acute post-operative timing.

Question 4

A 10-year-old boy presents with a 3-week history of right hip pain and a limp, without antecedent trauma. Physical examination reveals limited internal rotation and abduction of the right hip. Radiographs show sclerosis and flattening of the right femoral epiphysis. What is the most likely diagnosis?





Explanation

The age (peak incidence 4-10 years), presentation (atraumatic hip pain, limp), and radiographic findings (sclerosis, flattening of the femoral epiphysis) are classic for Legg-Calvé-Perthes disease (LCPD), which is idiopathic avascular necrosis of the femoral head. SCFE typically occurs in older, obese adolescents. DDH is usually diagnosed in infancy. Transient synovitis is acute and self-limiting. Septic arthritis would present with more acute, severe pain, fever, and systemic signs.

Question 5

Which of the following ligaments is the primary static stabilizer preventing anterior translation of the tibia on the femur?





Explanation

The Anterior Cruciate Ligament (ACL) is the primary static stabilizer preventing excessive anterior translation of the tibia relative to the femur and also limits internal rotation. The PCL prevents posterior translation. The MCL and LCL provide valgus and varus stability, respectively. The patellar tendon connects the patella to the tibia and is involved in knee extension.

Question 6

A 55-year-old painter presents with chronic right shoulder pain, worse with overhead activities. Examination reveals pain with resisted abduction and external rotation, and a positive Neer's and Hawkins' sign. Plain radiographs are unremarkable. Which of the following is the most likely diagnosis?





Explanation

The patient's age, occupation, pain with overhead activities, and positive impingement signs (Neer's, Hawkins') are highly suggestive of subacromial impingement syndrome, which often involves rotator cuff tendinopathy (especially supraspinatus). Adhesive capsulitis presents with global range of motion restriction. Glenohumeral OA would show joint space narrowing on X-ray. Bicipital tendinopathy typically causes anterior shoulder pain, and AC joint arthritis pain is localized to the AC joint.

Question 7

A 28-year-old male sustains a spiral fracture of the mid-shaft of the tibia and a fracture of the fibula neck after a twisting injury. On examination, he has numbness in the dorsum of his foot and weakness in ankle dorsiflexion and great toe extension. Which nerve is most likely injured?





Explanation

The deep peroneal nerve (DPN) is a branch of the common peroneal nerve. It provides motor innervation to the anterior compartment muscles of the leg (dorsiflexors of the ankle and extensors of the toes) and sensory innervation to the first web space of the foot. Injury to the common peroneal nerve, which often occurs with fibular neck fractures, can lead to foot drop (weakness in dorsiflexion and toe extension). The specific sensory loss to the dorsum of the foot (excluding the first web space, which is deep peroneal) points to the superficial peroneal nerve, also a branch of the common peroneal nerve. Therefore, both common peroneal and deep peroneal nerve injuries are plausible, but the pattern of weakness and sensory loss points strongly to the deep peroneal nerve for motor function of dorsiflexion and toe extension, and superficial peroneal for the dorsum of the foot sensory. Given the options, the deep peroneal nerve injury explains the motor deficits, and the superficial peroneal nerve explains sensory loss. However, a fibular neck fracture is classic for common peroneal nerve injury which contains both, and the motor deficit described is deep peroneal. Let's re-evaluate. The question states numbness in the dorsum of the foot and weakness in ankle dorsiflexion and great toe extension. The dorsum of the foot sensation is primarily superficial peroneal nerve, while ankle dorsiflexion and great toe extension are deep peroneal nerve functions. Since the common peroneal nerve divides into superficial and deep peroneal nerves near the fibular neck, an injury at the fibular neck typically affects the common peroneal nerve, manifesting in both superficial and deep peroneal nerve deficits. Among the choices, the deep peroneal nerve specifically accounts for the motor weakness in dorsiflexion and toe extension. If 'Common Peroneal Nerve' was an option, it would be the most comprehensive answer. Since it's not, and the motor deficit is specific, deep peroneal is the best fit for the motor component. Let's consider the sensory part more carefully. Numbness in the dorsum of the foot implies superficial peroneal. However, the first web space (deep peroneal) might also be involved. Without more precision on sensory, focusing on motor, deep peroneal is correct for motor. If the superficial peroneal was selected, it wouldn't account for motor weakness. Therefore, deep peroneal nerve is the best answer given the motor symptoms listed.

Question 8

Which of the following conditions is characterized by osteochondrosis of the navicular bone?





Explanation

Kohler's disease is osteochondrosis of the navicular bone, presenting with foot pain in children. Sever's disease is calcaneal apophysitis. Osgood-Schlatter disease is traction apophysitis of the tibial tubercle. Freiberg's disease is osteochondrosis of the metatarsal head (most commonly the second). Legg-Calvé-Perthes disease is avascular necrosis of the femoral head.

Question 9

A 4-year-old child presents with a Galeazzi sign (apparent shortening of one thigh with hips and knees flexed) and unequal skin folds in the groin. What is the most appropriate initial diagnostic imaging study?





Explanation

The clinical signs (Galeazzi sign, unequal skin folds) are suggestive of Developmental Dysplasia of the Hip (DDH). In children under 4-6 months, ultrasound is the preferred imaging modality because the femoral head is largely cartilaginous and not ossified, making X-rays unreliable. However, for a 4-year-old, ossification is sufficient, and plain radiographs of the pelvis (AP and frog-leg lateral views) are the primary initial diagnostic imaging study to assess hip morphology, acetabular index, and femoral head position. MRI and CT are typically reserved for surgical planning or more complex cases. Bone scintigraphy is not indicated for DDH.

Question 10

What is the most common primary malignant bone tumor in children and adolescents?





Explanation

Osteosarcoma is the most common primary malignant bone tumor in children and adolescents, typically peaking in the second decade of life. Ewing's sarcoma is the second most common. Chondrosarcoma and fibrosarcoma are more common in adults. Multiple myeloma is a plasma cell dyscrasia primarily affecting older adults.

Question 11

A 45-year-old construction worker presents with insidious onset, aching pain in his right elbow, aggravated by gripping and wrist extension. Physical examination reveals tenderness over the lateral epicondyle and pain with resisted wrist extension with the elbow extended. What is the most likely diagnosis?





Explanation

The symptoms (pain over the lateral epicondyle, aggravated by gripping and resisted wrist extension) are classic for lateral epicondylitis, commonly known as Tennis elbow. This is an overuse tendinopathy affecting the common extensor origin. Medial epicondylitis involves the common flexor origin. Olecranon bursitis involves swelling over the olecranon. Ulnar nerve entrapment would present with paresthesia in the small finger and ulnar half of the ring finger. A radial head fracture would have an acute traumatic onset.

Question 12

A 60-year-old male with a history of chronic alcoholism presents with atraumatic right hip pain and a limp. Radiographs show a crescent sign and collapse of the superior aspect of the femoral head. What is the most likely diagnosis?





Explanation

The history of chronic alcoholism is a significant risk factor for Avascular Necrosis (AVN) of the femoral head. The radiographic finding of a crescent sign (subchondral collapse) is pathognomonic for late-stage AVN, preceding femoral head collapse. Osteoarthritis would show diffuse joint space narrowing and osteophytes. Septic arthritis would be acute with systemic signs. Transient osteoporosis is self-limiting and less severe. Stress fracture has a different radiographic appearance and history.

Question 13

Which of the following statements regarding the management of clubfoot (Talipes Equinovarus) is TRUE?





Explanation

The Ponseti method is the gold standard initial treatment for congenital clubfoot. It involves a series of gentle manipulations and plaster casts, changed weekly, followed by a percutaneous Achilles tenotomy in most cases, and then a foot abduction brace to maintain correction. Surgical correction is reserved for failed conservative treatment. Bracing is crucial for preventing recurrence and is typically continued for several years, usually until around age 4-5. The deformity involves all aspects of the foot, including hindfoot equinus and varus, and forefoot adduction and supination.

Question 14

A 25-year-old basketball player lands awkwardly and feels a 'pop' in his knee. He experiences immediate pain and swelling. On examination, a positive Lachman test is noted. Which ligament is most likely injured?





Explanation

A 'pop' sensation, immediate pain and swelling (hemarthrosis), and a positive Lachman test (anterior translation of the tibia on the femur with the knee in 20-30 degrees of flexion) are classic signs of an Anterior Cruciate Ligament (ACL) tear. MCL injuries typically result from valgus stress and show tenderness over the medial joint line. PCL injuries result from a direct blow to the tibia or hyperflexion. LCL injuries result from varus stress. Patellar ligament injury would affect the extensor mechanism.

Question 15

What is the most common site for a stress fracture in a distance runner?





Explanation

The tibia is the most common site for stress fractures in distance runners, particularly the proximal or distal thirds. Other common sites include the metatarsals (especially second and third), fibula, femur, and navicular bone. The femoral shaft is less common than the tibia or metatarsals for stress fractures in runners.

Question 16

A 6-year-old child presents with a painful swollen left knee and fever. Labs show elevated ESR and CRP, and a white blood cell count of 18,000/uL. Aspiration of the knee joint yields cloudy fluid with a WBC count of 75,000/uL, 90% neutrophils, and positive Gram stain for Staphylococcus aureus. What is the immediate next step in management?





Explanation

This clinical scenario, lab findings, and joint fluid analysis are diagnostic of septic arthritis. Septic arthritis is an orthopedic emergency, especially in children, due to the rapid destruction of articular cartilage. The immediate next step is emergent surgical irrigation and debridement of the joint (often arthroscopic in larger joints like the knee), followed by appropriate intravenous antibiotics. Delay can lead to irreversible joint damage. Oral antibiotics are insufficient, and MRI, while helpful, is not the immediate therapeutic intervention.

Question 17

In evaluating a patient with scoliosis, which of the following Cobb angle measurements typically warrants surgical intervention in an adolescent with progressive idiopathic scoliosis?





Explanation

For progressive idiopathic scoliosis in adolescents, surgical correction is generally recommended for curves greater than 45-50 degrees to prevent further progression and mitigate potential pulmonary compromise. Curves 20-40 degrees often warrant bracing, especially if progressive in a growing child. Curves less than 20 degrees are typically observed. The threshold for surgery can vary slightly based on skeletal maturity, curve pattern, and patient symptoms, but >50 degrees is a common general guideline.

Question 18

Which of the following is considered a relative contraindication to total knee arthroplasty?





Explanation

Active knee infection is an absolute contraindication to total knee arthroplasty due to the high risk of periprosthetic joint infection. Obesity (BMI > 40) is a relative contraindication due to increased surgical risks and potential for poorer outcomes, but not an absolute one. Age is generally not a contraindication itself, but rather the patient's physiological status and comorbidities are considered. ACL deficiency is common in patients undergoing TKA for OA and is typically addressed by the prosthesis design. Rheumatoid arthritis is an indication for TKA.

Question 19

A 30-year-old male sustains a complete transection of the median nerve at the wrist. Which of the following muscles would NOT be affected?





Explanation

A complete transection of the median nerve at the wrist would affect the thenar muscles (Opponens pollicis, Abductor pollicis brevis, superficial head of Flexor pollicis brevis) and the lumbricals to the index and middle fingers. The Adductor pollicis muscle is primarily innervated by the ulnar nerve, specifically the deep branch. Therefore, it would not be affected by a median nerve transection at the wrist.

Question 20

What is the characteristic histological finding in Paget's disease of bone?





Explanation

Paget's disease of bone is characterized by a disorganized and accelerated remodeling process. Histologically, this leads to a 'mosaic' or 'jigsaw puzzle' pattern of lamellar bone due to haphazard deposition of new bone. It involves increased osteoclast activity followed by increased and disorganized osteoblast activity. Brown tumors are seen in hyperparathyroidism. Osteophytes are seen in osteoarthritis.

Question 21

A 50-year-old female presents with severe pain and swelling in the first metatarsophalangeal (MTP) joint, which started suddenly last night. Examination reveals a red, hot, swollen, and exquisitely tender joint. Labs show elevated serum uric acid. What is the most appropriate initial management?





Explanation

The clinical presentation (acute monoarticular arthritis, severe inflammation, elevated uric acid) is highly suggestive of acute gout. The most appropriate initial management for an acute gout attack is to rapidly reduce inflammation and pain. This is typically achieved with colchicine, NSAIDs (e.g., indomethacin), or oral corticosteroids. Allopurinol is a uric acid-lowering therapy used for long-term management to prevent future attacks, but it should not be started during an acute attack as it can worsen symptoms. Intra-articular steroid injection can be considered for isolated joint involvement but is often used if oral medications are contraindicated. Surgical debridement is not indicated.

Question 22

Which type of Salter-Harris fracture involves a fracture through the physis AND the epiphysis?





Explanation

Salter-Harris classification for physeal fractures: Type I: S = Slipped (through the physis only). Type II: A = Above (through physis and metaphysis). Type III: L = Lower (through physis and epiphysis). Type IV: T = Through (through metaphysis, physis, and epiphysis). Type V: R = Rammed (crush injury to physis). Therefore, Type IV involves a fracture through the physis AND the epiphysis (and metaphysis).

Question 23

A 70-year-old female with severe osteoporosis sustains a fragility fracture of the distal radius. Which of the following is the most appropriate long-term pharmacological agent to reduce future fracture risk?





Explanation

For a patient with a fragility fracture and severe osteoporosis, bisphosphonates (e.g., Alendronate, Risedronate, Zoledronic acid) are the first-line pharmacological agents to significantly reduce the risk of future fractures by inhibiting osteoclast activity. Calcium and Vitamin D supplementation are essential adjuncts but often insufficient alone for severe osteoporosis. NSAIDs are for pain relief, not fracture prevention. Oral corticosteroids can worsen osteoporosis. ERT can be used, but bisphosphonates are generally preferred as first-line for primary osteoporosis treatment due to their efficacy and broader applicability, especially given the age and fracture history.

Question 24

A 40-year-old male develops a painful lump in his plantar fascia near the medial calcaneal tuberosity. He reports worsening pain with first steps in the morning and after prolonged sitting. What is the most likely diagnosis?





Explanation

The symptoms (pain in the plantar aspect of the foot, worse with first steps in the morning and after rest, tenderness near the medial calcaneal tuberosity) are classic for plantar fasciitis. Achilles tendinitis is posterior heel pain. Tarsal tunnel syndrome involves nerve compression with numbness/tingling. Morton's neuroma is pain between metatarsal heads. A stress fracture would have a different pain pattern and potentially different imaging findings.

Question 25

Which of the following describes the typical clinical presentation of a patient with a posterior hip dislocation?





Explanation

Posterior hip dislocations, the most common type, typically result from a dashboard injury in MVCs. The classic presentation is a shortened limb, with the hip held in a position of adduction, internal rotation, and flexion. Anterior hip dislocations present with abduction and external rotation.

Question 26

A 16-year-old male presents with worsening pain and swelling in his distal femur for the past 3 months. Radiographs show a lytic lesion with a 'sunburst' periosteal reaction and Codman's triangle. What is the most likely diagnosis?





Explanation

The patient's age (adolescent), location (distal femur), and classic radiographic findings (lytic lesion with 'sunburst' periosteal reaction and Codman's triangle) are highly suggestive of osteosarcoma, the most common primary malignant bone tumor in this age group. Ewing's sarcoma can also show aggressive features but often presents with an 'onion skin' periosteal reaction. Osteochondroma and enchondroma are benign. Giant cell tumor typically occurs in young adults and is epiphyseal.

Question 27

Which of the following arteries is most at risk during surgical fixation of a displaced supracondylar humerus fracture in a child?





Explanation

The brachial artery is intimately associated with the distal humerus and is the most commonly injured neurovascular structure in displaced supracondylar humerus fractures. Injury to the brachial artery can lead to Volkmann's ischemic contracture. Other nerves (median, radial, ulnar) can also be injured, but the brachial artery is a primary concern for vascular compromise.

Question 28

A 22-year-old male sustains a traumatic anterior shoulder dislocation. After successful closed reduction, which of the following is the most important instruction to give the patient to prevent recurrence?





Explanation

After a traumatic anterior shoulder dislocation, especially in younger patients who have a high risk of recurrence, immobilization in a sling (typically for 3-4 weeks) is crucial to allow the labral-ligamentous structures to heal. Avoiding positions of abduction and external rotation (the 'at-risk' position for anterior dislocation) during the healing phase is paramount. Immediate surgical stabilization is not indicated for a first-time dislocation in most cases. Aggressive range of motion or maintaining the arm in the 'at-risk' position would promote recurrence.

Question 29

What is the primary function of the menisci in the knee joint?





Explanation

The menisci (medial and lateral) are C-shaped fibrocartilaginous structures that primarily increase the contact area between the femoral condyles and tibial plateau, thereby improving articular congruence and distributing compressive loads across the knee joint. They also play a role in shock absorption, joint lubrication, and stability, but load distribution and congruence are their main biomechanical functions. They do not initiate flexion, provide primary collateral stability (that's ligaments), synthesize synovial fluid (that's the synovium), or act as direct attachment points for the quadriceps (that's the patella and patellar tendon).

Question 30

A 75-year-old female presents with acute severe back pain after a minor fall. Radiographs show a compression fracture of the T12 vertebral body. She has no neurological deficits. Which of the following is the most appropriate initial management?





Explanation

For an osteoporotic compression fracture without neurological deficits, the initial management is typically conservative, focusing on pain control, activity modification, and possibly bracing. Opioid analgesics are often needed initially. Vertebroplasty or kyphoplasty may be considered if pain is refractory to conservative measures, but it is not an emergent 'within 24 hours' procedure. MRI is indicated if there are neurological symptoms or suspicion of malignancy, but not routinely for an uncomplicated osteoporotic fracture. Biopsy is not the immediate first step unless malignancy is highly suspected (e.g., history of cancer, atypical fracture pattern).

Question 31

Which of the following nerve compressions typically causes numbness and tingling in the thumb, index, and middle fingers, especially at night?





Explanation

Carpal tunnel syndrome is caused by compression of the median nerve within the carpal tunnel. Its classic symptoms include numbness, tingling, and pain in the median nerve distribution (thumb, index, middle, and radial half of the ring finger), often worse at night or with repetitive activities. Cubital tunnel syndrome (ulnar nerve at elbow) affects the small and ulnar half of the ring finger. Guyon's canal syndrome (ulnar nerve at wrist) affects similar fingers but typically spares the hypothenar muscles in early stages. Radial tunnel syndrome causes pain in the forearm, not numbness. Pronator teres syndrome is a proximal median nerve compression.

Question 32

A 14-year-old obese male presents with a painful limp and external rotation of the affected limb. Radiographs of the hip show widening and irregularity of the physis, and posterior and inferior displacement of the femoral epiphysis relative to the metaphysis. What is the most appropriate management?





Explanation

The patient's age, obesity, painful limp, external rotation, and specific radiographic findings are pathognomonic for a Slipped Capital Femoral Epiphysis (SCFE). The most appropriate management, regardless of stability (though described as painful, suggesting instability), is immediate in situ screw fixation to prevent further slippage and promote physeal closure. Weight-bearing and observation are contraindicated. Closed reduction can cause further damage to the blood supply of the femoral head and is generally avoided. Open reduction and osteotomy are reserved for severe, chronic, or failed in situ fixation cases.

Question 33

What is the most common organism causing osteomyelitis in healthy children?





Explanation

Staphylococcus aureus is the most common causative organism for acute hematogenous osteomyelitis in healthy children and adults across all age groups. E. coli and Pseudomonas are more common in specific scenarios (e.g., genitourinary infections, IV drug users, puncture wounds through shoes). S. pyogenes is less common, and H. influenzae was more common before widespread vaccination.

Question 34

Which of the following factors is most strongly associated with an increased risk of revision total hip arthroplasty due to aseptic loosening?





Explanation

Younger patient age at primary total hip arthroplasty is strongly associated with an increased risk of revision due to aseptic loosening, primarily because a longer life expectancy means more activity and a longer duration for wear and biologic response to occur, leading to osteolysis and loosening. While obesity can increase the risk of complications, and bearing surfaces can influence wear, age is a dominant factor for the long-term risk of aseptic loosening. Cemented femoral components have shown excellent long-term results in appropriate patient populations.

Question 35

A patient presents with a painful trigger finger, where the finger catches or locks in flexion and then snaps straight. Which anatomical structure is primarily involved in this condition?





Explanation

Trigger finger (stenosing tenosynovitis) is caused by inflammation and thickening of the flexor tendon sheath and/or the flexor tendons themselves, specifically at the A1 pulley. This creates a disparity between the size of the tendon and the pulley, causing the tendon to catch as it attempts to glide through. The A1 pulley is located at the metacarpal head. Other pulleys (A2, etc.) are further distal, and the tendons and muscles listed are involved in finger movement but the A1 pulley is the site of pathology.

Question 36

Regarding compartment syndrome of the forearm, which of the following is the most reliable clinical sign?





Explanation

The '6 Ps' are commonly taught for compartment syndrome (Pain, Pallor, Pulselessness, Paresthesia, Paralysis, Poikilothermia). However, pain out of proportion to injury, especially pain with passive stretching of the muscles in the affected compartment, is generally considered the earliest and most reliable clinical sign. Pallor, pulselessness, and paralysis are late signs, indicating severe ischemia, and often portend poor outcomes.

Question 37

Which type of orthopaedic implant is typically used for compression osteosynthesis in diaphyseal long bone fractures?





Explanation

A Dynamic Compression Plate (DCP) is specifically designed to achieve interfragmentary compression across a fracture site by eccentric screw placement, which then allows the plate to pull the fragments together as screws are tightened. Intramedullary nails provide load-sharing internal fixation. External fixators are typically temporary. Locking plates provide angular stability but are not primarily designed for compression osteosynthesis. K-wires provide temporary fixation.

Question 38

What is the most common cause of non-union in long bone fractures?





Explanation

Insufficient blood supply to the fracture fragments (avascularity) is the most common and critical factor leading to non-union, especially in specific fracture sites like the femoral neck, scaphoid, or talar neck. Other factors like infection, inadequate immobilization, interposition of soft tissue, and metabolic factors also play a role, but vascularity is paramount. Excessive rigid fixation can lead to stress shielding, and early weight-bearing can cause instability, but avascularity is the primary biological reason for non-union.

Question 39

A patient with a chronic history of rheumatoid arthritis develops sudden onset of neck pain, occipital headache, and myelopathic symptoms. Imaging reveals atlantoaxial instability with C1-C2 subluxation. What is the most appropriate initial management?





Explanation

Atlantoaxial instability with myelopathic symptoms in a rheumatoid arthritis patient is an urgent condition. The presence of neurological deficits due to spinal cord compression necessitates immediate surgical stabilization (C1-C2 fusion) to prevent irreversible neurological damage. Conservative measures like physical therapy, medication, or observation are inappropriate and potentially dangerous in this setting. Cervical traction might be used acutely but is not definitive management.

Question 40

Which of the following structures is most commonly injured in a 'terrible triad' injury of the elbow?





Explanation

The 'terrible triad' of the elbow consists of a radial head fracture, a coronoid process fracture, and a rupture of the ulnar collateral ligament (medial collateral ligament of the elbow). This combination often leads to elbow instability and requires operative management.

Question 41

A patient presents with a painful snapping sensation on the medial side of the knee during flexion and extension. Palpation reveals tenderness over the medial tibial condyle just distal to the joint line. What is the most likely diagnosis?





Explanation

The symptoms (painful snapping, tenderness on the medial tibial condyle just distal to the joint line) are characteristic of pes anserine bursitis. This condition involves inflammation of the bursa located deep to the conjoined tendons of the sartorius, gracilis, and semitendinosus muscles (the pes anserinus). Medial meniscus tears usually cause pain directly at the joint line. MCL injury involves tenderness over the ligament. Patellofemoral pain is anterior knee pain. OA would have broader symptoms.

Question 42

What is the primary role of Vitamin D in bone health?





Explanation

The primary role of Vitamin D (specifically its active form, calcitriol) in bone health is to promote the intestinal absorption of calcium and phosphate. This ensures adequate mineral availability for bone mineralization. It also has effects on osteoblasts and osteoclasts, and PTH regulation, but its main direct action is on gut absorption.

Question 43

Which surgical approach for total hip arthroplasty is known for having the lowest rate of dislocation?





Explanation

The anterior approach to total hip arthroplasty is often touted for its muscle-sparing nature (working between muscle planes) and typically has a reported lower rate of post-operative dislocation compared to the posterior approach, which involves detachment of the short external rotators. While other approaches also have good results, the anterior approach is frequently associated with a lower dislocation risk in the hands of experienced surgeons.

Question 44

A 5-year-old child presents with a high fever, refusal to bear weight on the right leg, and exquisite tenderness over the distal femur metaphysis. Blood cultures grow methicillin-sensitive Staphylococcus aureus. Radiographs are normal. What is the most appropriate next step?





Explanation

This is a classic presentation of acute osteomyelitis in a child (fever, localized bone pain, refusal to bear weight, positive blood cultures, normal initial radiographs). Given the high suspicion and positive blood cultures, immediate initiation of appropriate intravenous antibiotics is crucial to treat the infection and prevent bone destruction. Radiographs may be normal early in the course (before 7-10 days). MRI or bone scan can help localize the lesion but starting antibiotics should not be delayed. Surgical drainage is indicated if there is an abscess or no response to antibiotics, but not as the initial step after positive blood cultures.

Question 45

Which nerve is most commonly injured with a midshaft humerus fracture?





Explanation

The radial nerve courses in the spiral groove along the posterior aspect of the humerus shaft, making it highly susceptible to injury during midshaft humerus fractures. Injury can result in wrist drop and sensory deficits on the dorsum of the hand. The median and ulnar nerves are more medially located, and the axillary nerve is more proximal.

Question 46

What is the definitive treatment for symptomatic synovial chondromatosis of the knee?





Explanation

Synovial chondromatosis is a benign condition characterized by the formation of cartilaginous nodules within the synovial membrane, which can detach and form loose bodies within the joint. For symptomatic cases, the definitive treatment is arthroscopic removal of the loose bodies and partial or complete synovectomy to remove the source of the chondromas and prevent recurrence. Conservative measures are usually ineffective, and TKA is only considered for end-stage arthritis caused by the condition.

Question 47

Which of the following conditions is characterized by anterior knee pain, often exacerbated by prolonged sitting or climbing stairs, due to abnormal tracking of the patella?





Explanation

Anterior knee pain, especially worsened by activities that load the patellofemoral joint (e.g., prolonged sitting, climbing stairs, squatting), is characteristic of patellofemoral pain syndrome (PFPS), also historically known as chondromalacia patellae when referring to cartilage softening. This condition often stems from patellar maltracking or muscle imbalances. Patellar tendinopathy causes pain inferior to the patella. Osgood-Schlatter is tibial tubercle apophysitis in adolescents. Fat pad impingement and plica syndrome are less common causes of similar symptoms.

Question 48

What is the most common ligament injured in an ankle inversion injury?





Explanation

The anterior talofibular ligament (ATFL) is the weakest of the lateral ankle ligaments and is the most commonly injured ligament in an ankle inversion injury (sprain). In more severe inversion injuries, the calcaneofibular ligament (CFL) and then the posterior talofibular ligament (PTFL) may also be injured. The deltoid ligament is on the medial side and resists eversion. Syndesmotic ligaments are injured in high ankle sprains.

Question 49

A patient is diagnosed with a 'drop foot' due to L5 radiculopathy. Which muscle is primarily responsible for ankle dorsiflexion and is therefore most affected?





Explanation

The tibialis anterior is the primary dorsiflexor of the ankle. L5 radiculopathy commonly affects the muscles innervated by the deep peroneal nerve, which includes the tibialis anterior, leading to foot drop (inability to dorsiflex the ankle). Gastrocnemius and soleus are plantarflexors. Tibialis posterior is an invertor and plantarflexor. Peroneus longus is an evertor and plantarflexor.

Question 50

Which of the following is the most sensitive imaging modality for detecting early avascular necrosis (AVN) of the femoral head?





Explanation

MRI is the most sensitive imaging modality for detecting early avascular necrosis (AVN) of the femoral head. It can identify changes in bone marrow edema and signal intensity patterns before changes become apparent on plain radiographs (which may be normal for several months after symptom onset). CT scans are good for bone detail but less sensitive than MRI for early AVN. Bone scintigraphy can show increased uptake but is less specific than MRI. Ultrasound is not used for AVN diagnosis.

Question 51

What is the most common location for osteochondritis dissecans (OCD) in the knee?





Explanation

The most common location for osteochondritis dissecans (OCD) in the knee is the lateral aspect of the medial femoral condyle. This location accounts for approximately 85% of all knee OCD lesions. Other less common sites include the lateral femoral condyle and the patella.

Question 52

A 60-year-old male with a history of prostate cancer presents with new onset severe low back pain and bilateral lower extremity weakness. MRI shows a large epidural mass compressing the spinal cord at T10. What is the most appropriate immediate management?





Explanation

For patients with suspected or confirmed malignant spinal cord compression (SCC), the immediate priority is to reduce edema and inflammation around the spinal cord to preserve neurological function. High-dose intravenous corticosteroids (e.g., dexamethasone) are the mainstay of initial treatment. This provides temporary relief and buys time for definitive treatment. While emergent surgical decompression or radiation therapy will be necessary, corticosteroid administration is the immediate first step prior to these interventions and often initiated even before confirmatory imaging if SCC is highly suspected. Chemotherapy and physical therapy are not immediate treatments for acute SCC.

Question 53

Which of the following tendons forms part of the 'rotator cuff' of the shoulder?





Explanation

The rotator cuff is composed of four muscles and their tendons: supraspinatus, infraspinatus, teres minor, and subscapularis (SITS muscles). The supraspinatus is one of these four. The long head of the biceps brachii passes through the rotator cuff but is not part of it. Pectoralis major, deltoid, and teres major are not rotator cuff muscles.

Question 54

What is the primary anatomical structure involved in De Quervain's tenosynovitis?





Explanation

De Quervain's tenosynovitis is an inflammatory condition affecting the tendons of the abductor pollicis longus (APL) and extensor pollicis brevis (EPB) as they pass through the first dorsal compartment of the wrist. It causes pain on the radial side of the wrist, exacerbated by gripping or thumb movements, and a positive Finkelstein's test.

Question 55

A patient with a history of intravenous drug use presents with acute onset fever and severe back pain localized to the lumbar spine. MRI shows signal changes consistent with discitis and osteomyelitis at L3-L4. What is the most appropriate initial management?





Explanation

Given the history of IV drug use and MRI findings consistent with discitis and osteomyelitis, an infection is highly probable. The most appropriate initial management is to obtain a biopsy (either CT-guided percutaneous or open) for culture and histology to identify the causative organism, followed by empiric intravenous antibiotics. Surgical debridement may be necessary later if conservative measures fail or neurological compromise develops, but direct identification of the pathogen is crucial for targeted therapy. Physical therapy, NSAIDs, observation, or bracing alone are insufficient for an active spinal infection.

Question 56

In a patient with a displaced femoral neck fracture, what is the most significant risk associated with delaying definitive surgical fixation?





Explanation

Delayed definitive surgical fixation of a displaced femoral neck fracture significantly increases the risk of complications, particularly non-union and avascular necrosis (AVN) of the femoral head. This is because the blood supply to the femoral head, which is already tenuous, is further compromised by the fracture and prolonged displacement. While other complications like pain and DVT are also concerns, the risk to the femoral head's viability is paramount and time-sensitive.

Question 57

What is the 'circle of Willis' equivalent for the hip joint, providing crucial vascular supply to the femoral head?





Explanation

The medial circumflex femoral artery (MCFA) is the most critical artery supplying the femoral head, particularly its lateral epiphyseal branch. Disruption of the MCFA, often seen in femoral neck fractures, is a major contributor to avascular necrosis. While other arteries (lateral circumflex femoral, obturator) contribute, the MCFA is considered the primary and most important. There isn't a 'circle of Willis' equivalent for the hip in the same anastomotic sense, but the MCFA's role is dominant.

Question 58

A 1-year-old child presents with an inability to bear weight on the left leg, fever, and localized swelling and warmth over the distal tibia. Radiographs show periosteal reaction and lucency in the metaphysis. What is the most likely diagnosis?





Explanation

The clinical presentation (fever, localized pain, swelling, refusal to bear weight) and radiographic findings (periosteal reaction, lucency in metaphysis) in a young child are highly suggestive of acute hematogenous osteomyelitis. The metaphysis is a common site due to its rich blood supply and sluggish flow. Toddler's fracture is a non-displaced spiral fracture of the tibia, typically without fever. Osteosarcoma and Ewing's sarcoma are less common at this age and have different radiographic features (though some overlap). Rickets is a metabolic bone disease affecting growth plates, not an acute infectious process.

Question 59

Which of the following statements regarding the treatment of mallet finger is true?





Explanation

Mallet finger is an injury to the extensor tendon at the distal interphalangeal (DIP) joint, resulting in an inability to fully extend the DIP joint. The standard conservative treatment involves continuous splinting of the DIP joint in full extension for 6-8 weeks (or longer), while allowing full PIP joint motion. Surgical repair is rarely indicated for closed injuries. Immobilizing in flexion would worsen the deformity. It's an extensor tendon injury, not flexor. Buddy taping is insufficient for effective immobilization of the DIP joint.

Question 60

What is the most common benign bone tumor?





Explanation

Osteochondroma is by far the most common benign bone tumor, accounting for 20-50% of all benign bone tumors and 10-15% of all bone tumors. It is characterized by an exostosis with a cartilaginous cap. Enchondroma and osteoid osteoma are also common but less frequent than osteochondroma.

Question 61

A patient undergoing an anterior cervical discectomy and fusion (ACDF) develops hoarseness post-operatively. Which nerve is most likely injured?





Explanation

Hoarseness after anterior cervical spine surgery (like ACDF) is a well-known complication due to injury or irritation of the recurrent laryngeal nerve. This nerve, a branch of the vagus nerve, innervates most of the intrinsic muscles of the larynx. Injury can occur during retraction or direct trauma. The phrenic nerve supplies the diaphragm, and its injury would cause breathing difficulties. Vagus nerve injury can cause broader issues, but hoarseness points specifically to the recurrent laryngeal branch. Brachial plexus injury would cause upper limb neurological deficits.

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Dr. Mohammed Hutaif
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