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OMSB Orthopedic Surgery (OEORTHO) study materials
OMSB Orthopedic Surgery (OEORTHO) study resources

OMSB Orthopedic Surgery (OEORTHO) practice questions

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Question 1Orthopedics

A 24-year-old man sustains a closed tibial shaft fracture after a motorcycle crash. He has a pulseless foot, a tense calf, and pain out of proportion with the injury. Which is the most appropriate immediate management step?

  1. Elevation of the limb and observation
  2. Application of a cast and repeat vascular examination in six hours
  3. Aspiration of the compartment to confirm the diagnosis before surgery
  4. Urgent fasciotomy of all compartments Correct answer.

Explanation

This presentation is acute compartment syndrome, a surgical emergency in which raised intracompartmental pressure compromises perfusion and threatens limb viability. Urgent complete fasciotomy of all involved compartments is the definitive treatment and should not be delayed for imaging or measurement. Observation, casting, or needle aspiration wastes time and increases the risk of Volkmann ischemic contracture and amputation.

Question 2Orthopedics

Which nerve is most commonly injured during the posterior approach to the hip for total hip arthroplasty?

  1. Sciatic nerve Correct answer.
  2. Lateral femoral cutaneous nerve
  3. Obturator nerve
  4. Femoral nerve

Explanation

The sciatic nerve lies posterior to the acetabulum and short external rotators, so it is at risk during posterior surgical approaches to the hip. Injury may present as foot drop or sensory loss in the sciatic distribution postoperatively. The femoral, obturator, and lateral femoral cutaneous nerves are not in the posterior surgical field.

Question 3Orthopedics

A 70-year-old woman has a displaced femoral neck fracture with significant displacement. Which treatment is generally preferred in an independent, previously ambulatory patient of this age?

  1. Total hip arthroplasty Correct answer.
  2. Traction and bed rest
  3. Percutaneous pinning in situ
  4. Cannulated screw fixation

Explanation

Displaced intracapsular femoral neck fractures in older patients carry a high risk of avascular necrosis and nonunion after internal fixation. Arthroplasty, particularly total hip arthroplasty in previously independent patients, allows early weight bearing and lowers reoperation risk. Internal fixation is reserved for minimally displaced fractures or younger patients, and nonoperative traction is inappropriate.

Question 4Orthopedics

Which radiographic finding is most characteristic of developmental dysplasia of the hip in a walking-age child?

  1. Premature fusion of the triradiate cartilage
  2. Delayed ossification of the femoral head with a shallow acetabulum Correct answer.
  3. Enlargement of the femoral head with a deep acetabulum
  4. Widening of the joint space with normal acetabular coverage

Explanation

In developmental dysplasia, the acetabulum is shallow and the femoral head ossifies late and is laterally and superiorly displaced. These findings reflect inadequate coverage of the femoral head. Premature triradiate fusion and acetabular deepening are not features of dysplasia.

Question 5Orthopedics

A 12-year-old boy has anterior knee pain that worsens with activity and improves with rest. Examination shows tenderness over the tibial tubercle. Which is the most likely diagnosis?

  1. Sinding-Larsen-Johansson syndrome
  2. Patellar dislocation
  3. Septic arthritis of the knee
  4. Osgood-Schlatter disease Correct answer.

Explanation

Osgood-Schlatter disease is traction apophysitis of the tibial tubercle and presents with activity-related anterior knee pain in adolescents. Tenderness is localized to the tibial tubercle, and symptoms typically resolve with activity modification. Sinding-Larsen-Johansson syndrome affects the inferior pole of the patella, and septic arthritis presents with acute systemic illness.

Question 6Orthopedics

Which organism is the most common cause of acute osteomyelitis in children in most series?

  1. Neisseria meningitidis
  2. Mycobacterium tuberculosis
  3. Staphylococcus aureus Correct answer.
  4. Clostridium perfringens

Explanation

Staphylococcus aureus is the most frequently isolated pathogen in acute hematogenous osteomyelitis in children. Empiric antibiotic therapy is therefore directed against it while awaiting cultures. Meningococcus, mycobacteria, and clostridia are uncommon causes in this setting.

Question 7Orthopedics

A patient sustains a fall on an outstretched hand and has a distal radius fracture with dorsal angulation and dorsal displacement of the distal fragment. What is the eponym for this fracture?

  1. Colles fracture Correct answer.
  2. Barton fracture
  3. Smith fracture
  4. Chauffeur fracture

Explanation

A Colles fracture is a distal radius fracture with dorsal angulation and dorsal displacement, typically from a fall on an outstretched hand. A Smith fracture is the volar counterpart, while Barton and chauffeur fractures involve different fracture patterns and joint surfaces.

Question 8Orthopedics

Which finding best supports a diagnosis of a complete rotator cuff tear on physical examination?

  1. Pain only at the end range of active elevation
  2. Marked weakness in external rotation and a positive drop arm sign Correct answer.
  3. Tenderness over the acromioclavicular joint
  4. Full painless active range of motion

Explanation

Complete rotator cuff tears often produce measurable weakness in specific movements, such as external rotation for infraspinatus involvement, and a positive drop arm sign when the supraspinatus is deficient. Pain-limited motion without true weakness suggests tendinopathy or impingement. Full painless motion and isolated acromioclavicular tenderness do not indicate a full-thickness tear.

Question 9Orthopedics

In a patient with a suspected scaphoid fracture and normal initial radiographs, what is the most appropriate next step?

  1. Perform immediate open reduction and internal fixation without imaging
  2. Order a bone scan after six weeks of free movement
  3. Reassure the patient and allow full activity immediately
  4. Immobilize the wrist and repeat imaging in one to two weeks or obtain early MRI Correct answer.

Explanation

Scaphoid fractures are frequently occult on initial radiographs, and missed fractures risk nonunion and avascular necrosis. The standard approach is immobilization with repeat radiographs or early MRI or CT to confirm the diagnosis. Allowing unrestricted activity, operating without confirmation, or delaying evaluation for weeks is inappropriate.

Question 10Orthopedics

Which pattern on radiographs suggests a posterior shoulder dislocation?

  1. Superior migration of the humeral head
  2. Inferior subluxation with a widened joint space
  3. Volar displacement of the distal humerus
  4. Light bulb sign with an internally rotated humeral head Correct answer.

Explanation

Posterior dislocations fix the humerus in internal rotation, producing the light bulb sign, and are often missed on a single anteroposterior view. A complete trauma series including axillary or scapular Y views is needed to confirm the diagnosis. Superior migration and inferior subluxation are features of other conditions such as cuff arthropathy or inferior instability.

Question 11Orthopedics

A 35-year-old runner has lateral knee pain that worsens with downhill running. Examination shows tenderness over the lateral femoral epicondyle and pain with resisted knee flexion. What is the most likely diagnosis?

  1. Popliteal cyst
  2. Iliotibial band syndrome Correct answer.
  3. Patellofemoral pain syndrome
  4. Medial collateral ligament sprain

Explanation

Iliotibial band syndrome causes lateral knee pain from friction of the band over the lateral femoral epicondyle, aggravated by downhill running and resisted knee flexion. Patellofemoral pain is anterior, and medial collateral ligament sprain follows a valgus stress mechanism with medial tenderness. A popliteal cyst produces posterior knee swelling.

Question 12Orthopedics

Which is the most appropriate initial management for a hemodynamically stable patient with an isolated, minimally displaced pelvic ring fracture?

  1. Protected weight bearing with analgesia and early mobilization Correct answer.
  2. Immediate application of a pelvic binder and massive transfusion
  3. Skeletal traction for six weeks
  4. Emergent open reduction and internal fixation

Explanation

Isolated, mechanically stable pelvic ring fractures without hemodynamic instability can be managed nonoperatively with analgesia, protected weight bearing, and early mobilization to reduce complications. Pelvic binders and massive transfusion are for unstable bleeding pelvic injuries, and operative fixation is reserved for unstable or displaced patterns.

Question 13Orthopedics

Which feature distinguishes a closed femoral shaft fracture in a child younger than one year as suspicious for non-accidental injury?

  1. A fracture with mild displacement
  2. A fracture associated with bruising at the injury site
  3. A transverse fracture after a witnessed fall
  4. A spiral fracture in a non-ambulatory infant Correct answer.

Explanation

A femoral shaft fracture in a non-ambulatory infant, particularly a spiral pattern, is unusual because such injuries generally require substantial force. This should prompt a thorough evaluation for non-accidental trauma, including skeletal survey and child protection assessment. Transverse fractures after witnessed trauma and mild displacement are not inherently suspicious.

Question 14Orthopedics

A 60-year-old diabetic patient has a deep foot ulcer with exposed bone and probing to bone. Which diagnosis must be excluded?

  1. Osteomyelitis Correct answer.
  2. Morton neuroma
  3. Tarsal tunnel syndrome
  4. Plantar fasciitis

Explanation

A diabetic foot ulcer probing to bone raises concern for underlying osteomyelitis, which requires imaging, and often bone biopsy, to confirm and guide treatment. Plantar fasciitis, Morton neuroma, and tarsal tunnel syndrome cause pain without deep ulceration or exposed bone.

Question 15Orthopedics

Which is the most appropriate initial treatment for a patient with a displaced, closed humeral shaft fracture with intact neurovascular status?

  1. Hanging cast with strict immobilization for eight weeks
  2. Functional bracing with early shoulder and elbow motion Correct answer.
  3. Immediate open reduction and internal fixation in all cases
  4. Primary shoulder arthrodesis

Explanation

Most closed humeral shaft fractures with acceptable alignment and intact neurovascular function heal well with functional bracing and early range of motion. Operative fixation is reserved for open fractures, vascular injury, brachial plexus injury, nonunion, or unacceptable alignment. Arthrodesis is not a primary treatment for acute fractures.

Question 16Orthopedics

A 55-year-old man has chronic low back pain and neurogenic claudication relieved by leaning forward. MRI shows ligamentum flavum hypertrophy and facet arthropathy without disc herniation. What is the most likely diagnosis?

  1. Vertebral compression fracture
  2. Lumbar disc herniation
  3. Lumbar spinal stenosis Correct answer.
  4. Ankylosing spondylitis

Explanation

Neurogenic claudication relieved by flexion, together with ligamentum flavum hypertrophy and facet arthropathy, is characteristic of degenerative lumbar spinal stenosis. Flexion increases canal diameter and relieves symptoms, unlike vascular claudication. Disc herniation, inflammatory spondylitis, and compression fracture produce different clinical and imaging findings.

Question 17Orthopedics

Which is the most appropriate treatment for a Gustilo-Anderson type IIIB open tibial fracture?

  1. External fixation alone without soft tissue coverage
  2. Delayed debridement after one week
  3. Primary wound closure without debridement
  4. Urgent debridement, intravenous antibiotics, and flap coverage after skeletal stabilization Correct answer.

Explanation

Type IIIB open fractures involve extensive soft tissue loss with periosteal stripping requiring flap coverage. Management includes urgent debridement, intravenous antibiotics, skeletal stabilization, and early soft tissue coverage to reduce infection and nonunion. Primary closure without debridement or delayed treatment is inappropriate.

Question 18Orthopedics

A 14-year-old boy has a slipped capital femoral epiphysis. Which statement best describes the typical presentation?

  1. Acute severe pain with a shortened, internally rotated limb
  2. Painless limp with full symmetric hip rotation
  3. Groin or knee pain with an externally rotated limb and limited internal rotation Correct answer.
  4. Buttock pain with fever and elevated inflammatory markers

Explanation

Slipped capital femoral epiphysis often presents with insidious groin or referred knee pain, an externally rotated limb, and limited internal rotation in an obese adolescent. The limb is externally rotated because the femoral head remains in the acetabulum while the neck displaces anteriorly. Acute shortening with internal rotation suggests fracture or dislocation, and fever suggests infection.

Question 19Orthopedics

A patient has a complete radial nerve palsy after a humeral shaft fracture. Which examination finding is expected?

  1. Wrist drop with preserved elbow flexion Correct answer.
  2. Loss of sensation over the medial forearm
  3. Inability to flex the distal interphalangeal joint of the index finger
  4. Inability to abduct the shoulder

Explanation

The radial nerve supplies the wrist and finger extensors, so injury produces wrist drop, while elbow flexion is preserved because the musculocutaneous nerve supplies the biceps and brachialis. Sensation is lost over the dorsal first web space rather than the medial forearm, which is the ulnar distribution. Shoulder abduction and index distal interphalangeal flexion are mediated by the axillary and anterior interosseous nerves, respectively.

Question 20Orthopedics

Which is the definitive treatment for a chronic, symptomatic full-thickness rotator cuff tear in an active patient who has failed conservative therapy?

  1. Arthroscopic or open rotator cuff repair Correct answer.
  2. Shoulder manipulation under anesthesia alone
  3. Total shoulder arthroplasty in all cases
  4. Continued corticosteroid injections indefinitely

Explanation

Symptomatic full-thickness rotator cuff tears that fail nonoperative treatment in active patients are treated with surgical repair, usually arthroscopic or mini-open. Repeated steroid injections may weaken tendon, and manipulation alone does not restore cuff continuity. Arthroplasty is reserved for advanced cuff tear arthropathy.

Question 21Orthopedics

A 65-year-old woman has a distal radius fracture with dorsal comminution and intra-articular extension. Which factor most strongly predicts loss of reduction after closed treatment?

  1. Minimal initial displacement
  2. Dorsal comminution and intra-articular extension Correct answer.
  3. Absence of associated ulnar styloid fracture
  4. Patient right-handedness

Explanation

Dorsal comminution and intra-articular extension are recognized predictors of instability and loss of reduction after closed treatment of distal radius fractures. These features often favor operative fixation, particularly in older patients with osteopenic bone. Minimal displacement, ulnar styloid status, and handedness do not predict collapse.

Question 22Orthopedics

A 30-year-old man has a posterior hip dislocation after a dashboard injury. Which factor most strongly increases the risk of avascular necrosis of the femoral head?

  1. Prolonged time to reduction Correct answer.
  2. Associated acetabular rim fracture
  3. Male sex
  4. Associated sciatic nerve palsy

Explanation

The femoral head blood supply is compromised by sustained dislocation, and the duration before reduction is the strongest modifiable predictor of avascular necrosis. Prompt closed reduction is therefore the priority. Acetabular rim fracture and sciatic palsy affect prognosis and treatment but are less directly tied to avascular necrosis than time to reduction.

Question 23Orthopedics

A 45-year-old woman has a lytic lesion in the distal femur with a sunburst periosteal reaction and a soft tissue mass. Which diagnosis is most likely?

  1. Enchondroma
  2. Simple bone cyst
  3. Non-ossifying fibroma
  4. Osteosarcoma Correct answer.

Explanation

A destructive metaphyseal lesion with a sunburst periosteal reaction and soft tissue extension in a young adult is highly suggestive of osteosarcoma. Enchondroma, non-ossifying fibroma, and simple bone cysts are benign lesions with characteristic benign features and no aggressive periosteal reaction.

Question 24Orthopedics

A patient has a supracondylar humeral fracture with an absent radial pulse but a well-perfused hand. Which initial step is most appropriate after urgent closed reduction and pinning?

  1. Routine prophylactic fasciotomy of the forearm
  2. Immediate amputation
  3. Reassess perfusion and consider vascular exploration if the pulse does not return Correct answer.
  4. Observation for 48 hours without reassessment

Explanation

In supracondylar fractures with a pulseless but well-perfused hand, the brachial artery is often in spasm or temporarily occluded, and perfusion frequently returns after reduction and pinning. The limb should be reassessed and vascular exploration pursued if perfusion remains compromised. Immediate amputation and routine fasciotomy are not indicated.

Question 25Orthopedics

Which biomechanical principle best explains the use of a locking plate in an osteoporotic proximal humerus fracture?

  1. Screw fixation in the humeral head is independent of plate compression on bone Correct answer.
  2. The plate relies on friction between bone and plate for stability
  3. The screws must engage only the far cortex to avoid cutout
  4. The plate must span the entire humerus to share load

Explanation

Locking plates create a fixed-angle construct in which the head screws lock to the plate, providing stability independent of plate-to-bone compression, which is advantageous in osteoporotic bone. Nonlocking plates rely on friction, and unicortical or far-cortex-only fixation increases the risk of cutout. Spanning the entire humerus is not a principle of proximal humeral plating.

Question 26Orthopedics

A 10-year-old boy presents with hip pain and a limp. He is afebrile. Radiographs show a normal joint space and no fracture. Which diagnosis should be strongly considered?

  1. Septic arthritis of the hip
  2. Legg-Calvé-Perthes disease Correct answer.
  3. Developmental dysplasia of the hip
  4. Slipped capital femoral epiphysis

Explanation

Legg-Calvé-Perthes disease typically presents in children aged 4–10 years with insidious hip pain and a limp, often without systemic symptoms. Radiographs may be normal early, so a high index of suspicion and further imaging (e.g., MRI) are warranted. Septic arthritis usually presents with fever and an acutely painful hip.

Question 27Orthopedics

Which nerve is most commonly injured during a direct lateral approach to the hip for total hip arthroplasty?

  1. Femoral nerve
  2. Obturator nerve
  3. Superior gluteal nerve Correct answer.
  4. Sciatic nerve

Explanation

The superior gluteal nerve is at risk during the direct lateral approach because it innervates the gluteus medius and minimus and runs close to the greater trochanter. Injury can lead to postoperative abductor weakness and a Trendelenburg gait. The sciatic nerve is more commonly at risk in posterior approaches.

Question 28Orthopedics

A 25-year-old man sustains a tibial plateau fracture. Which classification system is most commonly used to describe the fracture pattern and guide treatment?

  1. Neer classification
  2. Salter-Harris classification
  3. Gustilo-Anderson classification
  4. Schatzker classification Correct answer.

Explanation

The Schatzker classification divides tibial plateau fractures into six types based on involvement of the medial and lateral condyles and the degree of comminution or depression. It is widely used to guide surgical decision-making. The other systems apply to open fractures, shoulder fractures, or physeal injuries.

Question 29Orthopedics

Which muscle is the primary flexor of the elbow?

  1. Triceps brachii
  2. Brachialis Correct answer.
  3. Brachioradialis
  4. Biceps brachii

Explanation

The brachialis is the strongest and primary flexor of the elbow, inserting on the ulna and providing flexion regardless of forearm rotation. The biceps brachii is a powerful supinator and flexor, but it is not the primary flexor. The brachioradialis assists flexion, and the triceps extends the elbow.

Question 30Orthopedics

A 70-year-old woman has a fragility fracture of the distal radius. Which underlying condition should be evaluated as a contributing factor?

  1. Paget disease of bone
  2. Rheumatoid arthritis
  3. Gout
  4. Osteoporosis Correct answer.

Explanation

Fragility fractures, such as a distal radius fracture from a low-energy fall, are a hallmark of osteoporosis. Evaluation with bone mineral density testing and assessment for secondary causes is recommended. Rheumatoid arthritis, gout, and Paget disease can affect bone but are not the primary cause of typical fragility fractures.

Question 31Orthopedics

A 30-year-old man has a transverse fracture of the patella with 4 mm of displacement and intact extensor mechanism. What is the most appropriate initial management?

  1. Patellectomy
  2. Long leg cast immobilization in extension Correct answer.
  3. Immediate weight-bearing as tolerated
  4. Open reduction and internal fixation

Explanation

Minimally displaced patellar fractures with an intact extensor mechanism can be treated nonoperatively with cast or brace immobilization in extension. Surgical fixation is indicated for displaced fractures or disruption of the extensor mechanism. Patellectomy is reserved for severe comminution and is not first-line.

Question 32Orthopedics

Which imaging modality is most sensitive for detecting early osteomyelitis?

  1. Ultrasound
  2. CT scan
  3. MRI Correct answer.
  4. Plain radiography

Explanation

MRI is highly sensitive for early osteomyelitis because it detects marrow edema and soft tissue involvement before bony destruction is visible on radiographs. Plain radiographs may be normal for up to two weeks. CT and ultrasound are less sensitive for early marrow changes.

Question 33Orthopedics

A 45-year-old woman has a complete Achilles tendon rupture. Which clinical test is most specific?

  1. McMurray test
  2. Simmonds test
  3. Thompson test Correct answer.
  4. Lachman test

Explanation

The Thompson test (calf squeeze test) is highly specific for Achilles tendon rupture; absence of plantarflexion when the calf is squeezed indicates a complete tear. The Simmonds test is another name for the Thompson test but is less commonly used. McMurray and Lachman tests assess the knee.

Question 34Orthopedics

A 55-year-old man has a distal biceps tendon rupture. Which finding is most characteristic on examination?

  1. Positive Tinel sign at the elbow
  2. Loss of wrist flexion
  3. Weakness in elbow flexion and supination Correct answer.
  4. Weakness in elbow extension

Explanation

Distal biceps tendon rupture leads to weakness in elbow flexion and, more notably, supination, along with a palpable defect and possible reverse Popeye deformity. Elbow extension is powered by the triceps. Tinel sign and wrist flexion relate to other nerve or muscle injuries.

Question 35Orthopedics

A 60-year-old man has a displaced femoral neck fracture. Which treatment is most appropriate for a healthy, active patient of this age?

  1. Internal fixation with cannulated screws
  2. Traction and bed rest
  3. Hemiarthroplasty
  4. Total hip arthroplasty Correct answer.

Explanation

For active, healthy older adults with displaced femoral neck fractures, total hip arthroplasty provides better function and lower reoperation rates compared with hemiarthroplasty or internal fixation. Internal fixation is generally reserved for younger patients or nondisplaced fractures. Traction is not definitive treatment.

Question 36Orthopedics

A 35-year-old woman has a Colles fracture. Which deformity is typically seen on physical examination?

  1. Dinner fork deformity Correct answer.
  2. Swan neck deformity
  3. Claw hand
  4. Garden spade deformity

Explanation

A Colles fracture is a distal radius fracture with dorsal angulation and displacement, producing a dinner fork deformity. Garden spade deformity is associated with Smith fracture (volar displacement). Claw hand and swan neck deformity are seen in nerve palsy and rheumatoid arthritis, respectively.

Question 37Orthopedics

A 28-year-old man has a Monteggia fracture-dislocation. Which bone is dislocated?

  1. Radial head Correct answer.
  2. Capitellum
  3. Ulnar shaft
  4. Distal radioulnar joint

Explanation

A Monteggia fracture-dislocation consists of a fracture of the proximal ulna with dislocation of the radial head. A Galeazzi fracture-dislocation involves a distal radius fracture with distal radioulnar joint dislocation. The capitellum is part of the distal humerus and is not dislocated in this pattern.

Question 38Orthopedics

A 50-year-old man has a complete ulnar nerve palsy at the elbow. Which finding is expected on examination?

  1. Clawing of the ring and small fingers Correct answer.
  2. Loss of sensation over the thenar eminence
  3. Inability to abduct the shoulder
  4. Wrist drop

Explanation

Ulnar nerve palsy causes clawing of the ring and small fingers due to loss of intrinsic hand muscle function, along with sensory loss in the ulnar distribution. Wrist drop is caused by radial nerve palsy. Shoulder abduction is mediated by the axillary nerve and suprascapular nerve. Thenar sensation is median nerve.

Question 39Orthopedics

A 40-year-old woman has a both-bone forearm fracture. Which factor most strongly indicates the need for surgical fixation?

  1. Minimal pain at presentation
  2. Displacement and instability after reduction Correct answer.
  3. Age over 30 years
  4. Presence of a single fracture line

Explanation

Both-bone forearm fractures require anatomic reduction to restore pronation and supination. Surgical fixation is indicated when reduction cannot be maintained or when displacement is significant. Age, fracture pattern, and pain level are less reliable indicators for surgery.

Question 40Orthopedics

A 65-year-old man has a degenerative rotator cuff tear and severe shoulder pain that has failed conservative management. Which imaging study is most useful for preoperative planning?

  1. CT scan
  2. Plain radiographs
  3. MRI of the shoulder Correct answer.
  4. Ultrasound of the shoulder

Explanation

MRI provides detailed assessment of tendon retraction, muscle atrophy, and fatty infiltration, which are important for preoperative planning in rotator cuff repair. Ultrasound is useful for diagnosis but less reliable for muscle quality. Plain radiographs and CT are better for bony anatomy.

Question 41Orthopedics

A 30-year-old man has a Bankart lesion after anterior shoulder dislocation. What does this lesion involve?

  1. Fracture of the greater tuberosity
  2. Detachment of the labrum from the anterior glenoid Correct answer.
  3. Tear of the posterior labrum
  4. Compression fracture of the humeral head

Explanation

A Bankart lesion is an avulsion of the anterior labrum from the glenoid rim, commonly seen after anterior shoulder dislocation. A Hill-Sachs lesion is a compression fracture of the humeral head. Greater tuberosity fracture and posterior labral tears are different entities.

Question 42Orthopedics

A 50-year-old woman has a distal humerus fracture with severe comminution and osteoporosis. Which treatment is most appropriate?

  1. Open reduction and internal fixation
  2. Total elbow arthroplasty Correct answer.
  3. Elbow disarticulation
  4. Closed reduction and cast immobilization

Explanation

Total elbow arthroplasty is an option for severely comminuted distal humerus fractures in older, low-demand patients with osteoporosis, as it provides reliable pain relief and function. Internal fixation may be difficult in osteoporotic bone. Cast immobilization risks stiffness and malunion, and amputation is not appropriate.

Question 43Orthopedics

A 60-year-old man has lumbar spinal stenosis with neurogenic claudication. Which finding on physical examination is most consistent?

  1. Absent ankle reflexes bilaterally
  2. Pain worsened by sitting
  3. Positive straight leg raise
  4. Relief of symptoms with forward flexion Correct answer.

Explanation

Neurogenic claudication from lumbar stenosis typically improves with forward flexion (e.g., leaning on a shopping cart) because it increases the spinal canal diameter. Pain is often worsened by extension and walking. Straight leg raise is more indicative of radiculopathy, and absent reflexes suggest neuropathy.

Question 44Orthopedics

A 25-year-old man has a complete spinal cord injury at T10. Which function is most likely preserved?

  1. Upper extremity motor function Correct answer.
  2. Bowel and bladder control
  3. Sexual function
  4. Ambulation without assistance

Explanation

A T10 level spinal cord injury affects the lower trunk and legs but preserves upper extremity function, as the cervical and upper thoracic segments are intact. Ambulation, bowel/bladder control, and sexual function are typically impaired with complete injuries at this level.

Question 45Orthopedics

A 70-year-old woman has a vertebral compression fracture. Which factor most strongly increases the risk of future fractures?

  1. Male sex
  2. Regular weight-bearing exercise
  3. Low bone mineral density Correct answer.
  4. High body mass index

Explanation

Low bone mineral density is a strong predictor of future fragility fractures, including vertebral compression fractures. Other risk factors include prior fracture, age, and glucocorticoid use. Male sex, high BMI, and exercise are not risk factors; exercise is protective.

Question 46Orthopedics

A 30-year-old woman has a complete peroneal nerve palsy after knee trauma. Which finding is expected?

  1. Foot drop Correct answer.
  2. Inability to invert the foot
  3. Loss of sensation over the medial leg
  4. Weakness in knee flexion

Explanation

Common peroneal nerve palsy causes foot drop due to weakness of the dorsiflexors and evertors, with sensory loss over the dorsum of the foot and lateral leg. Sensation over the medial leg is saphenous nerve. Inversion is primarily tibialis posterior (tibial nerve), and knee flexion is hamstrings (sciatic).

Question 47Orthopedics

A 55-year-old man has a high-energy tibial pilon fracture with severe soft tissue injury. Which factor most strongly influences the timing of definitive fixation?

  1. Degree of comminution
  2. Presence of a fibula fracture
  3. Patient's age
  4. Condition of the soft tissue envelope Correct answer.

Explanation

In pilon fractures, the soft tissue envelope is the primary determinant of surgical timing because severe swelling or blistering increases the risk of wound complications. Surgery is often delayed until soft tissues recover, using temporary external fixation. Age, fibula fracture, and comminution are secondary considerations.

Question 48Orthopedics

A 45-year-old man has a suspected compartment syndrome of the leg after a tibial fracture. Which finding is most reliable for diagnosis?

  1. Absent distal pulses
  2. Pain with passive stretch Correct answer.
  3. Pallor of the skin
  4. Decreased capillary refill

Explanation

Pain with passive stretch is the most sensitive and reliable clinical finding in compartment syndrome, often occurring before pulselessness or pallor. Pulselessness is a late and unreliable sign. Pallor and decreased capillary refill are also late and nonspecific.

Question 49Orthopedics

A 60-year-old woman has a distal radius fracture with intra-articular extension and severe comminution. Which treatment is most likely to restore articular congruity?

  1. Closed reduction and cast immobilization
  2. Percutaneous pinning without reduction
  3. External fixation alone
  4. Open reduction and internal fixation with a volar locking plate Correct answer.

Explanation

Open reduction and internal fixation with a volar locking plate allows direct visualization and restoration of articular congruity in comminuted intra-articular distal radius fractures. Closed reduction and casting often fails to maintain alignment. External fixation alone may not restore articular surface, and pinning without reduction is inadequate.

Question 50Orthopedics

A 35-year-old man has a femoral shaft fracture treated with an intramedullary nail. Which factor most increases the risk of nonunion?

  1. Early weight-bearing
  2. Fracture gap and instability Correct answer.
  3. Patient's sex
  4. Use of a reamed nail

Explanation

Nonunion risk is increased by fracture gap, instability, and poor blood supply. Reamed nailing and early weight-bearing generally promote healing. Patient sex alone is not a major risk factor.