Full Question & Answer Text (for Search Engines)
Question 1:
A 28-year-old male sustains a comminuted open tibia fracture (Gustilo-Anderson Type IIIB) after a motor vehicle accident. Initial management includes debridement, external fixation, and IV antibiotics. Two weeks later, he presents with persistent pain, fever, and purulent discharge from the wound. Which of the following is the most appropriate next step in management?
Options:
- Switch to oral antibiotics and continue external fixation.
- Perform repeat surgical debridement, obtain cultures, and continue IV antibiotics tailored to culture results.
- Remove the external fixator and apply a long leg cast.
- Initiate hyperbaric oxygen therapy immediately.
- Amputation below the knee due to suspected osteomyelitis.
Correct Answer: Perform repeat surgical debridement, obtain cultures, and continue IV antibiotics tailored to culture results.
Explanation:
The clinical presentation (persistent pain, fever, purulent discharge from an open fracture) strongly suggests osteomyelitis. The most appropriate next step is aggressive repeat surgical debridement to remove infected and necrotic tissue, obtain deep tissue cultures to identify the causative organism and guide antibiotic therapy, and continue appropriate IV antibiotics. Simply switching to oral antibiotics or casting without addressing the source of infection is inadequate. Hyperbaric oxygen can be an adjunct but not the primary intervention for active infection. Amputation is a salvage procedure considered after failure of limb preservation attempts.
Question 2:
A 65-year-old female with known osteoporosis falls and presents with acute severe back pain. Imaging reveals a T12 compression fracture. She has failed conservative management with pain medication and bracing for 6 weeks. Her pain is significantly impacting her quality of life. Which surgical intervention would be most appropriate at this stage?
Options:
- Spinal fusion from T10 to L2.
- Laminectomy and decompression.
- Vertebroplasty or kyphoplasty.
- Total discectomy at T12-L1.
- Posterior spinal instrumentation without fusion.
Correct Answer: Vertebroplasty or kyphoplasty.
Explanation:
For painful osteoporotic vertebral compression fractures refractory to conservative management, vertebroplasty or kyphoplasty are minimally invasive procedures designed to stabilize the fracture and alleviate pain by injecting bone cement into the collapsed vertebral body. Spinal fusion is typically reserved for unstable fractures or deformity correction. Laminectomy and discectomy are not indicated for isolated compression fractures without neural compression. Posterior instrumentation without fusion might be used for unstable fractures but is less common for isolated osteoporotic compression fractures failing conservative care.
Question 3:
A 35-year-old male presents with sudden onset excruciating left hip pain after a high-energy motor vehicle collision. He is found with his left hip flexed, adducted, and internally rotated. Pulses are palpable distally. Which of the following is the most critical immediate management step?
Options:
- Order an MRI of the hip.
- Administer strong analgesics and arrange for emergent closed reduction.
- Prepare for open reduction and internal fixation.
- Perform an arthrocentesis of the hip joint.
- Immobilize the hip in the deformed position and await elective surgery.
Correct Answer: Administer strong analgesics and arrange for emergent closed reduction.
Explanation:
The patient's presentation is classic for a posterior hip dislocation. This is an orthopedic emergency due to the high risk of avascular necrosis (AVN) of the femoral head and sciatic nerve injury. The most critical immediate step after assessing neurovascular status and administering analgesia is emergent closed reduction, ideally within 6 hours, to minimize the risk of AVN. Delay can significantly increase the risk of complications. MRI is useful after reduction to assess for occult fractures or soft tissue injuries, but not before emergent reduction. Open reduction is considered if closed reduction fails. Arthrocentesis is not indicated. Immobilizing in the deformed position will exacerbate complications.
Question 4:
Which of the following is a contraindication to total knee arthroplasty (TKA)?
Options:
- Obesity (BMI > 35).
- Age greater than 80 years.
- Uncontrolled active infection in the knee.
- Previous knee surgery.
- Mild rheumatoid arthritis.
Correct Answer: Uncontrolled active infection in the knee.
Explanation:
Uncontrolled active infection in the knee is an absolute contraindication to total knee arthroplasty because implanting a foreign body into an infected joint significantly increases the risk of periprosthetic joint infection, which is a devastating complication. Obesity, advanced age, previous knee surgery, and mild rheumatoid arthritis are relative contraindications or not contraindications at all, often managed with careful patient selection and optimization.
Question 5:
A 7-year-old boy presents with a supracondylar humerus fracture (Gartland Type III). Initial radiographs show significant displacement and rotation. Which neurovascular structure is most commonly at risk in this type of fracture?
Options:
- Radial nerve.
- Ulnar nerve.
- Median nerve and brachial artery.
- Axillary nerve.
- Musculocutaneous nerve.
Correct Answer: Median nerve and brachial artery.
Explanation:
Gartland Type III supracondylar humerus fractures are severely displaced and rotated, putting the median nerve and brachial artery at significant risk of injury due to their close proximity to the distal humerus. The radial nerve is also at risk but less commonly than the median nerve/brachial artery. Ulnar nerve injury is less common in extension-type supracondylar fractures but can occur with flexion-type fractures or during surgical manipulation. Axillary and musculocutaneous nerves are not typically injured in this fracture pattern.
Question 6:
A 50-year-old construction worker complains of right shoulder pain, especially when lifting his arm overhead. He describes a 'catching' sensation and weakness with abduction. Physical exam reveals a positive Neer's and Hawkins' test. Resisted external rotation is weak. What is the most likely diagnosis?
Options:
- Adhesive capsulitis.
- Glenohumeral osteoarthritis.
- Rotator cuff tear.
- Bicipital tendinitis.
- Acromioclavicular joint arthritis.
Correct Answer: Rotator cuff tear.
Explanation:
The patient's symptoms of pain with overhead activity, weakness with abduction and external rotation, and positive impingement signs (Neer's and Hawkins' tests) are highly suggestive of a rotator cuff tear. Resisted external rotation weakness specifically points to involvement of the supraspinatus or infraspinatus, both part of the rotator cuff. Adhesive capsulitis presents with global stiffness. Glenohumeral osteoarthritis typically causes grinding and limited range of motion, often in older patients. Bicipital tendinitis causes anterior shoulder pain. AC joint arthritis causes localized pain at the top of the shoulder.
Question 7:
What is the primary goal of surgical management for an unstable thoracolumbar burst fracture with neurological deficit?
Options:
- Early ambulation.
- Pain relief.
- Decompression of neural elements and stabilization of the spinal column.
- Prevention of kyphosis.
- Minimizing blood loss.
Correct Answer: Decompression of neural elements and stabilization of the spinal column.
Explanation:
For an unstable thoracolumbar burst fracture with neurological deficit, the primary surgical goals are to decompress the neural elements (spinal cord or cauda equina) that are compromised by retropulsed bone fragments or disc material, and to stabilize the spinal column to prevent further injury and allow for neurological recovery. While early ambulation, pain relief, and prevention of kyphosis are important secondary goals, and minimizing blood loss is a surgical principle, they are not the primary aims of the surgery itself in this specific context of instability and neurological compromise.
Question 8:
A 4-year-old child presents with a limp and right hip pain that started insidiously. X-rays show fragmentation and collapse of the right femoral head epiphysis. What is the most likely diagnosis?
Options:
- Septic arthritis of the hip.
- Developmental dysplasia of the hip (DDH).
- Slipped capital femoral epiphysis (SCFE).
- Legg-Calvé-Perthes disease.
- Transient synovitis.
Correct Answer: Legg-Calvé-Perthes disease.
Explanation:
The clinical presentation (limp, hip pain, insidious onset in a young child) combined with radiographic findings of fragmentation and collapse of the femoral head epiphysis is classic for Legg-Calvé-Perthes disease, which is avascular necrosis of the femoral head in children. Septic arthritis has an acute onset with systemic signs. DDH is a developmental abnormality. SCFE typically affects older, obese adolescents. Transient synovitis is a self-limiting inflammatory condition with normal X-rays.
Question 9:
Which of the following is a classic clinical triad for a ruptured Achilles tendon?
Options:
- Anterior ankle pain, swelling, difficulty walking.
- Posterior heel pain, palpable gap, positive Thompson test.
- Lateral ankle swelling, ecchymosis, inability to bear weight.
- Midfoot pain, pes planus, inability to perform single heel rise.
- Calf pain, numbness, weakness in plantarflexion.
Correct Answer: Posterior heel pain, palpable gap, positive Thompson test.
Explanation:
The classic clinical triad for a ruptured Achilles tendon includes posterior heel/calf pain, a palpable gap in the tendon (often 2-6 cm proximal to the calcaneal insertion), and a positive Thompson test (absence of plantarflexion when squeezing the calf muscle). The other options describe symptoms related to different conditions: anterior ankle pain (e.g., impingement), lateral ankle swelling (e.g., ankle sprain), midfoot pain (e.g., posterior tibial tendon dysfunction), or calf pain/numbness/weakness (e.g., nerve impingement or compartment syndrome).
Question 10:
In the management of an open fracture, what is the 'golden period' for surgical debridement to minimize infection risk?
Options:
- Within 6 hours.
- Within 12 hours.
- Within 24 hours.
- Within 48 hours.
- Within 72 hours.
Correct Answer: Within 6 hours.
Explanation:
The 'golden period' for surgical debridement of an open fracture to significantly reduce the risk of infection is generally considered to be within 6 hours of injury. While some studies suggest a broader window, earlier debridement is consistently associated with better outcomes. Beyond this window, the risk of bacterial proliferation and subsequent infection increases substantially.
Question 11:
A 22-year-old collegiate athlete sustains an injury to his knee during a soccer match. He reports hearing a 'pop,' followed by immediate swelling and inability to continue playing. Lachman test is positive. What is the most likely diagnosis?
Options:
- Medial collateral ligament (MCL) tear.
- Lateral collateral ligament (LCL) tear.
- Anterior cruciate ligament (ACL) tear.
- Posterior cruciate ligament (PCL) tear.
- Meniscus tear.
Correct Answer: Anterior cruciate ligament (ACL) tear.
Explanation:
The classic presentation of an ACL tear includes a 'pop' at the time of injury, immediate knee swelling (hemarthrosis), inability to continue activity, and a positive Lachman test (anterior translation of the tibia relative to the femur with the knee at 30 degrees flexion). While meniscal tears can also cause popping and swelling, the Lachman test is specific for ACL laxity. MCL and LCL tears present with valgus/varus instability respectively. PCL tears cause posterior instability.
Question 12:
Which of the following describes the most common type of Salter-Harris fracture involving the growth plate?
Options:
- Type I: Transverse fracture through the physis.
- Type II: Fracture through the physis and metaphysis.
- Type III: Fracture through the physis and epiphysis.
- Type IV: Fracture through the metaphysis, physis, and epiphysis.
- Type V: Crush injury of the physis.
Correct Answer: Type II: Fracture through the physis and metaphysis.
Explanation:
Salter-Harris Type II fractures are the most common type, accounting for approximately 75% of all physeal injuries. These fractures extend through the physis and exit into the metaphysis, typically leaving a 'Thurston Holland' fragment. Type I is a separation through the physis. Type III is intra-articular and involves the epiphysis. Type IV is intra-articular, involving metaphysis, physis, and epiphysis. Type V is a rare crush injury with a poor prognosis.
Question 13:
A 40-year-old female presents with persistent pain, stiffness, and catching in her right thumb MP joint. Radiographs show significant joint space narrowing and osteophytes. She has failed conservative management. What is the most appropriate surgical intervention?
Options:
- Flexor pollicis longus tenolysis.
- Carpometacarpal (CMC) joint arthroplasty.
- Metacarpophalangeal (MP) joint arthroplasty or fusion.
- De Quervain's release.
- Scaphoidectomy.
Correct Answer: Metacarpophalangeal (MP) joint arthroplasty or fusion.
Explanation:
The patient's symptoms and radiographic findings are indicative of osteoarthritis of the thumb metacarpophalangeal (MP) joint. For symptomatic MP joint arthritis refractory to conservative care, surgical options include MP joint arthroplasty (replacement) or fusion, which can provide pain relief and stability. CMC joint arthroplasty is for basilar thumb arthritis. De Quervain's release is for stenosing tenosynovitis of the abductor pollicis longus and extensor pollicis brevis. Scaphoidectomy is not relevant here. Flexor pollicis longus tenolysis is for trigger thumb.
Question 14:
Which of the following imaging modalities is most sensitive for detecting early osteomyelitis?
Options:
- Plain radiographs.
- CT scan.
- MRI.
- Bone scintigraphy (technetium-99m).
- Ultrasound.
Correct Answer: MRI.
Explanation:
MRI is generally considered the most sensitive imaging modality for detecting early osteomyelitis, often demonstrating changes within 24-48 hours of infection onset. It provides excellent soft tissue contrast, allowing visualization of marrow edema, abscess formation, and soft tissue involvement. Plain radiographs may take 7-10 days to show changes. CT scans are good for bony detail but less sensitive for early marrow changes. Bone scintigraphy is sensitive but not very specific for infection versus other bone activity. Ultrasound can detect soft tissue abscesses but is not ideal for bone marrow changes.
Question 15:
A 55-year-old male develops numbness and tingling in his left hand, specifically affecting the thumb, index, middle, and radial half of the ring finger. Symptoms are worse at night and with repetitive hand activities. Phalen's test is positive. What is the most likely diagnosis?
Options:
- Ulnar nerve entrapment at the elbow (cubital tunnel syndrome).
- Radial nerve palsy (wrist drop).
- Carpal tunnel syndrome.
- Cervical radiculopathy (C6/C7).
- Thoracic outlet syndrome.
Correct Answer: Carpal tunnel syndrome.
Explanation:
The symptoms described (numbness/tingling in the median nerve distribution, nocturnal exacerbation, worsening with activity, positive Phalen's test) are classic for carpal tunnel syndrome, which is compression of the median nerve at the wrist. Ulnar nerve entrapment affects the small finger and ulnar half of the ring finger. Radial nerve palsy affects the extensors and causes wrist drop. Cervical radiculopathy would likely involve neck pain and weakness. Thoracic outlet syndrome has broader neurovascular symptoms, often involving the entire arm.
Question 16:
What is the primary goal of Pilon fracture (distal tibia intra-articular) management?
Options:
- Achieve rigid internal fixation within 24 hours.
- Minimize soft tissue swelling and allow for soft tissue recovery before definitive fixation.
- Always perform primary arthrodesis.
- Utilize external fixation exclusively.
- Immediate full weight-bearing after surgery.
Correct Answer: Minimize soft tissue swelling and allow for soft tissue recovery before definitive fixation.
Explanation:
Pilon fractures are high-energy injuries often associated with severe soft tissue compromise. The primary goal of management is to minimize soft tissue swelling and allow for soft tissue recovery before definitive internal fixation, which often involves a staged approach (e.g., initial external fixation followed by definitive ORIF once the soft tissue envelope is favorable). Rushing to definitive fixation in the acute phase significantly increases the risk of wound complications, infection, and skin necrosis. Primary arthrodesis is reserved for severe, unsalvageable cases. External fixation is often used initially but not always exclusively as definitive treatment. Immediate full weight-bearing is contraindicated.
Question 17:
Which type of scoliosis typically presents in adolescence, has no identifiable cause, and is the most common form?
Options:
- Congenital scoliosis.
- Neuromuscular scoliosis.
- Syndromic scoliosis.
- Adolescent idiopathic scoliosis.
- Degenerative scoliosis.
Correct Answer: Adolescent idiopathic scoliosis.
Explanation:
Adolescent idiopathic scoliosis (AIS) is the most common type of scoliosis, affecting approximately 2-3% of adolescents. It typically presents in children aged 10-18 years, progresses during growth spurts, and has no identifiable underlying cause. Congenital scoliosis is due to vertebral anomalies. Neuromuscular scoliosis is associated with neurological conditions (e.g., cerebral palsy). Syndromic scoliosis is associated with specific syndromes. Degenerative scoliosis occurs in older adults due to spinal degeneration.
Question 18:
A 60-year-old male with chronic low back pain and bilateral leg pain, worse with standing and walking, and relieved by sitting or leaning forward (shopping cart sign), most likely has which of the following conditions?
Options:
- Lumbar disc herniation.
- Spondylolisthesis.
- Lumbar spinal stenosis.
- Sacroiliac joint dysfunction.
- Piriformis syndrome.
Correct Answer: Lumbar spinal stenosis.
Explanation:
The classic symptoms of neurogenic claudication, including bilateral leg pain worse with standing and walking, and relieved by sitting or leaning forward (the 'shopping cart sign'), are highly suggestive of lumbar spinal stenosis. This condition involves narrowing of the spinal canal, compressing the cauda equina. Lumbar disc herniation typically causes more acute radicular pain, often unilateral. Spondylolisthesis can cause back and leg pain but the claudication pattern is distinct to stenosis. Sacroiliac joint dysfunction causes localized buttock pain. Piriformis syndrome causes sciatic-like pain but usually without the classic claudication pattern.
Question 19:
What is the most common primary malignant bone tumor in children and young adults?
Options:
- Chondrosarcoma.
- Ewing sarcoma.
- Osteosarcoma.
- Multiple myeloma.
- Fibrosarcoma.
Correct Answer: Osteosarcoma.
Explanation:
Osteosarcoma is the most common primary malignant bone tumor in children and young adults (typically second decade of life). It is characterized by the production of osteoid by malignant cells. Ewing sarcoma is the second most common. Chondrosarcoma and fibrosarcoma are generally less common, and multiple myeloma is a malignancy of plasma cells affecting older adults, not a primary bone tumor in children.
Question 20:
The anterior drawer test of the ankle assesses the integrity of which ligament?
Options:
- Deltoid ligament.
- Calcaneofibular ligament.
- Posterior talofibular ligament.
- Anterior talofibular ligament.
- Anterior tibiofibular ligament.
Correct Answer: Anterior talofibular ligament.
Explanation:
The anterior drawer test of the ankle specifically assesses the integrity of the anterior talofibular ligament (ATFL), which is the most commonly injured ligament in ankle sprains. The test involves stabilizing the tibia and fibula with one hand and drawing the foot anteriorly with the other. Excessive anterior translation or a 'clunk' indicates ATFL laxity/tear. The calcaneofibular ligament and posterior talofibular ligament are assessed by other maneuvers.
Question 21:
Which of the following is a key management principle for compartment syndrome?
Options:
- Apply tight compression bandages to the affected limb.
- Elevate the limb above heart level to reduce swelling.
- Administer strong analgesics and observe closely.
- Perform emergent fasciotomy.
- Apply ice packs to the affected area.
Correct Answer: Perform emergent fasciotomy.
Explanation:
Compartment syndrome is a surgical emergency characterized by increased pressure within a confined osteofascial compartment, compromising blood flow and leading to tissue ischemia. The definitive treatment is emergent fasciotomy to decompress the compartments. Applying compression bandages, elevating the limb, or applying ice packs are all contraindicated as they can worsen ischemia. Analgesics might mask symptoms, delaying crucial diagnosis and treatment.
Question 22:
A 10-year-old obese male presents with a painful limp and external rotation of the affected leg, which worsens with activity. Radiographs show a widening and irregularity of the physis, with posterior and inferior displacement of the femoral head relative to the femoral neck. What is the most likely diagnosis?
Options:
- Legg-Calvé-Perthes disease.
- Transient synovitis of the hip.
- Septic arthritis of the hip.
- Developmental dysplasia of the hip (DDH).
- Slipped capital femoral epiphysis (SCFE).
Correct Answer: Slipped capital femoral epiphysis (SCFE).
Explanation:
The presentation of a painful limp, external rotation deformity, and classic radiographic findings (widening/irregularity of physis, posterior/inferior displacement of femoral head) in an obese adolescent male is pathognomonic for Slipped Capital Femoral Epiphysis (SCFE). Legg-Calvé-Perthes disease affects younger children and involves fragmentation/collapse of the femoral head. Transient synovitis is self-limiting and has normal X-rays. Septic arthritis presents acutely with fever and systemic signs. DDH is a neonatal/infant condition.
Question 23:
What is the primary indication for surgical intervention in patients with a herniated lumbar disc?
Options:
- Chronic low back pain lasting more than 6 months.
- Failed conservative management for at least 6 weeks.
- Radiographic evidence of disc herniation, regardless of symptoms.
- Progressive neurological deficit (e.g., motor weakness, cauda equina syndrome).
- Patients requesting immediate pain relief.
Correct Answer: Progressive neurological deficit (e.g., motor weakness, cauda equina syndrome).
Explanation:
The primary indication for urgent surgical intervention in patients with a herniated lumbar disc is the presence of a progressive neurological deficit, especially cauda equina syndrome (bowel/bladder dysfunction, saddle anesthesia, bilateral leg weakness). While failed conservative management (typically 6-12 weeks) is a common indication for elective surgery, it is not the most urgent. Chronic back pain alone is not a surgical indication for disc herniation. Radiographic evidence without correlating symptoms is insufficient.
Question 24:
Which bone is most commonly fractured in the wrist after a fall onto an outstretched hand?
Options:
- Triquetrum.
- Hamate.
- Lunate.
- Scaphoid.
- Pisiform.
Correct Answer: Scaphoid.
Explanation:
The scaphoid is the most commonly fractured carpal bone, typically occurring after a fall onto an outstretched hand (FOOSH) with the wrist hyperextended and radially deviated. Due to its precarious blood supply, scaphoid fractures are prone to nonunion and avascular necrosis, especially if not recognized and treated appropriately.
Question 25:
The 'terrible triad' of the elbow involves injury to which structures?
Options:
- Radial head fracture, coronoid fracture, MCL tear.
- Olecranon fracture, LCL tear, radial head dislocation.
- Radial head fracture, coronoid fracture, LCL tear.
- Distal humerus fracture, ulnar nerve injury, brachial artery injury.
- Medial epicondyle fracture, lateral epicondyle fracture, elbow dislocation.
Correct Answer: Radial head fracture, coronoid fracture, LCL tear.
Explanation:
The 'terrible triad' of the elbow consists of a posterior elbow dislocation, a radial head fracture, and a coronoid process fracture. These injuries combine to create a highly unstable elbow, often requiring surgical intervention for stability. The associated ligamentous injury in this context is typically the lateral collateral ligament (LCL) complex, not the MCL. The other options describe different injury patterns.
Question 26:
What is the primary characteristic that distinguishes osteosarcoma from Ewing sarcoma on histopathology?
Options:
- Presence of small round blue cells.
- Production of osteoid by malignant cells.
- Formation of cartilage matrix.
- Presence of multinucleated giant cells.
- Spindle cell morphology.
Correct Answer: Production of osteoid by malignant cells.
Explanation:
The defining characteristic of osteosarcoma is the production of osteoid (immature bone matrix) by malignant tumor cells. Ewing sarcoma is characterized by small, round, blue cells (similar to lymphoma or neuroblastoma) and often associated with the EWS-FLI1 translocation. Chondrosarcoma produces a cartilaginous matrix. Multinucleated giant cells are seen in giant cell tumors. Spindle cell morphology is less specific and seen in various soft tissue sarcomas and some bone tumors.
Question 27:
A 70-year-old male with long-standing bilateral knee osteoarthritis reports severe pain and functional limitation. He has undergone multiple intra-articular injections and physical therapy with minimal relief. Radiographs show tricompartmental severe degenerative changes. Which of the following is the most appropriate definitive treatment option?
Options:
- High tibial osteotomy.
- Arthroscopic debridement.
- Total knee arthroplasty.
- Patellectomy.
- Unicompartmental knee arthroplasty.
Correct Answer: Total knee arthroplasty.
Explanation:
For severe tricompartmental knee osteoarthritis that has failed extensive conservative management, total knee arthroplasty (TKA) is the gold standard definitive treatment. High tibial osteotomy is typically for younger, active patients with isolated medial compartment osteoarthritis. Arthroscopic debridement has limited long-term efficacy for advanced osteoarthritis. Patellectomy is rarely performed. Unicompartmental knee arthroplasty is for isolated single-compartment disease.
Question 28:
Which of the following is a contraindication for an MRI in a patient with suspected spinal cord injury?
Options:
- Pregnancy.
- Presence of a pacemaker or certain metallic implants.
- Claustrophobia.
- Renal insufficiency.
- Obesity.
Correct Answer: Presence of a pacemaker or certain metallic implants.
Explanation:
The presence of a pacemaker or certain ferrous metallic implants (e.g., older aneurysm clips, some shrapnel) is an absolute contraindication to MRI due to the strong magnetic field, which can interfere with device function or cause movement/heating of the metallic object. While pregnancy, claustrophobia, renal insufficiency (relevant for contrast), and obesity can be challenges, they are not absolute contraindications that preclude the MRI if critically indicated for spinal cord injury.
Question 29:
What is the most common cause of osteonecrosis (avascular necrosis) of the femoral head in adults?
Options:
- Trauma (e.g., hip dislocation, femoral neck fracture).
- Alcohol abuse.
- Corticosteroid use.
- Sickle cell disease.
- Gaucher's disease.
Correct Answer: Corticosteroid use.
Explanation:
Among the systemic causes, corticosteroid use is the most common non-traumatic cause of osteonecrosis of the femoral head in adults, often in a dose-dependent manner. Trauma (e.g., hip dislocation, femoral neck fracture) is also a significant cause, but corticosteroid use leads the list of atraumatic causes. Alcohol abuse, sickle cell disease, and Gaucher's disease are also risk factors but less common overall than corticosteroid use.
Question 30:
A patient undergoing total hip arthroplasty for osteoarthritis is at highest risk for which of the following complications in the immediate postoperative period?
Options:
- Periprosthetic fracture.
- Avascular necrosis of the femoral head.
- Heterotopic ossification.
- Deep vein thrombosis (DVT) and pulmonary embolism (PE).
- Loosening of the prosthetic components.
Correct Answer: Deep vein thrombosis (DVT) and pulmonary embolism (PE).
Explanation:
Patients undergoing major orthopedic surgery, especially total hip arthroplasty, are at highest risk for deep vein thrombosis (DVT) and subsequent pulmonary embolism (PE) in the immediate postoperative period. Prophylactic anticoagulation is standard to mitigate this risk. Periprosthetic fracture, avascular necrosis (of the patient's remaining bone, not a complication of the replaced head), heterotopic ossification, and loosening are also potential complications, but DVT/PE represents the most critical and life-threatening immediate postoperative risk requiring strict preventative protocols.
Question 31:
Which surgical approach for total hip arthroplasty typically carries the lowest risk of dislocation?
Options:
- Posterior approach.
- Anterolateral approach.
- Direct anterior approach.
- Lateral approach.
- Transtrochanteric approach.
Correct Answer: Direct anterior approach.
Explanation:
The direct anterior approach for total hip arthroplasty is generally associated with the lowest risk of postoperative dislocation compared to posterior or lateral approaches. This is because it spares the posterior soft tissue structures (posterior capsule, short external rotators) which are critical for hip stability. The posterior approach traditionally has the highest dislocation rate, while anterolateral and direct lateral approaches have intermediate rates.
Question 32:
What is the most appropriate initial management for a stable type I odontoid fracture?
Options:
- Emergent surgical fixation.
- Halo vest immobilization.
- Soft cervical collar for 6 weeks.
- Traction.
- Atlantoaxial fusion.
Correct Answer: Soft cervical collar for 6 weeks.
Explanation:
A Type I odontoid fracture is an oblique fracture of the odontoid tip, which is typically stable. It usually heals well with non-operative management, often with a rigid cervical collar (like a Miami J or Philadelphia collar) for 6-12 weeks. Halo vest immobilization or surgical fixation are generally reserved for more unstable Type II or Type III odontoid fractures. Traction is not indicated, and atlantoaxial fusion is a definitive surgical treatment for instability, not initial management for a stable Type I.
Question 33:
Which type of fracture is most susceptible to developing a nonunion due to its poor blood supply?
Options:
- Distal radius fracture.
- Tibial shaft fracture.
- Clavicle fracture.
- Femoral shaft fracture.
- Navicular fracture of the foot.
Correct Answer: Navicular fracture of the foot.
Explanation:
Fractures of the navicular bone (talonavicular joint in the foot) are known for their high rates of nonunion and avascular necrosis due to the bone's limited and often retrograde blood supply. Other bones with notoriously poor blood supply prone to nonunion include the scaphoid in the wrist and the femoral neck. Distal radius, tibial shaft, clavicle, and femoral shaft fractures, while they can nonunion, are not typically as prone as the navicular or scaphoid.
Question 34:
In the management of septic arthritis, what is the most critical initial step after diagnosis?
Options:
- Initiate broad-spectrum oral antibiotics.
- Immobilize the joint in a position of comfort.
- Perform emergent joint aspiration and start empiric IV antibiotics.
- Administer intra-articular corticosteroids.
- Schedule elective arthroscopy for debridement.
Correct Answer: Perform emergent joint aspiration and start empiric IV antibiotics.
Explanation:
Septic arthritis is a joint emergency. The most critical initial step after suspicion is emergent joint aspiration to confirm the diagnosis (cell count, Gram stain, culture) and immediately initiate empiric intravenous antibiotics. Delay in treatment can lead to rapid cartilage destruction and long-term joint damage. Oral antibiotics are insufficient initially. Intra-articular corticosteroids are contraindicated. Immobilization provides comfort but doesn't treat the infection. Elective arthroscopy might be needed for drainage/debridement but only after aspiration and antibiotics are started.
Question 35:
A 16-year-old male presents with worsening nocturnal pain in his right femur, which is relieved by aspirin. Radiographs show a small radiolucent nidus surrounded by sclerotic bone. What is the most likely diagnosis?
Options:
- Osteosarcoma.
- Ewing sarcoma.
- Osteoid osteoma.
- Chondroblastoma.
- Aneurysmal bone cyst.
Correct Answer: Osteoid osteoma.
Explanation:
The classic presentation of an osteoid osteoma is nocturnal pain that is characteristically relieved by NSAIDs (like aspirin), along with radiographic findings of a small radiolucent nidus surrounded by dense reactive sclerosis. This is a benign bone tumor. Osteosarcoma and Ewing sarcoma are malignant and would not typically respond so dramatically to aspirin. Chondroblastoma is an epiphyseal lesion. An aneurysmal bone cyst is expansile and lytic.
Question 36:
What is the primary anatomical structure involved in De Quervain's tenosynovitis?
Options:
- Extensor carpi ulnaris.
- Flexor pollicis longus.
- Extensor pollicis brevis and abductor pollicis longus.
- Flexor digitorum profundus.
- Extensor digitorum communis.
Correct Answer: Extensor pollicis brevis and abductor pollicis longus.
Explanation:
De Quervain's tenosynovitis is a painful condition affecting the tendons on the thumb side of the wrist, specifically involving stenosing tenosynovitis of the first dorsal compartment. This compartment contains the abductor pollicis longus (APL) and extensor pollicis brevis (EPB) tendons. Finkelstein's test is typically positive. The other tendons are located in different compartments or have different functions.
Question 37:
Which physical examination finding is highly specific for a meniscus tear in the knee?
Options:
- Positive Lachman test.
- Joint line tenderness with pain on twisting maneuvers (e.g., McMurray test).
- Valgus instability.
- Patellofemoral crepitus.
- Generalized knee effusion.
Correct Answer: Joint line tenderness with pain on twisting maneuvers (e.g., McMurray test).
Explanation:
Joint line tenderness combined with pain or a 'click' during specific twisting maneuvers (like the McMurray test) is highly suggestive of a meniscus tear. The McMurray test attempts to trap the torn meniscal fragment between the femur and tibia. A positive Lachman test indicates ACL injury. Valgus instability indicates MCL injury. Patellofemoral crepitus suggests patellofemoral arthritis or chondromalacia. Generalized knee effusion can be present with many knee pathologies.
Question 38:
In the context of spinal cord injury, what is Brown-Séquard syndrome characterized by?
Options:
- Complete loss of motor and sensory function below the level of injury.
- Loss of motor function with preservation of sensation.
- Loss of proprioception and vibratory sense ipsilaterally, with loss of pain and temperature contralaterally.
- Loss of pain and temperature below the level of injury, with preservation of proprioception and motor function.
- Flaccid paralysis and areflexia below the level of injury.
Correct Answer: Loss of proprioception and vibratory sense ipsilaterally, with loss of pain and temperature contralaterally.
Explanation:
Brown-Séquard syndrome results from hemisection of the spinal cord (e.g., due to penetrating trauma). It is characterized by ipsilateral loss of motor function, proprioception, and vibratory sense (due to corticospinal and dorsal column pathway damage), and contralateral loss of pain and temperature sensation (due to spinothalamic tract damage), typically 1-2 levels below the lesion. Complete loss of function is complete cord injury. Loss of motor with preserved sensation is anterior cord syndrome. Flaccid paralysis is spinal shock or cauda equina. Loss of pain/temp with preserved motor/proprioception can be central cord syndrome if only crossing fibers are affected or pure spinothalamic lesion.
Question 39:
What is the most appropriate initial management for acute calcific tendinitis of the shoulder?
Options:
- Surgical excision of the calcific deposit.
- Corticosteroid injection into the subacromial space.
- Physical therapy focusing on strengthening exercises.
- Aggressive massage and heat therapy.
- Immediate arthroscopic debridement.
Correct Answer: Corticosteroid injection into the subacromial space.
Explanation:
Acute calcific tendinitis of the shoulder can be exquisitely painful. Initial management often involves conservative measures such as rest, NSAIDs, and a subacromial corticosteroid injection, which can effectively reduce inflammation and pain. Surgical excision is reserved for chronic, refractory cases. Physical therapy for strengthening is not appropriate in the acute painful phase. Aggressive massage and heat can exacerbate symptoms. Arthroscopic debridement is a surgical intervention for failed conservative care.
Question 40:
A patient presents with persistent symptoms of cervical radiculopathy (C6 distribution) despite 8 weeks of conservative management including physical therapy, NSAIDs, and epidural steroid injections. MRI shows a large C5-C6 soft disc herniation. Which surgical procedure is typically considered the gold standard for this condition?
Options:
- Posterior cervical laminectomy.
- Anterior cervical discectomy and fusion (ACDF).
- Cervical laminoplasty.
- Posterior cervical foraminotomy.
- Artificial disc replacement.
Correct Answer: Anterior cervical discectomy and fusion (ACDF).
Explanation:
For cervical radiculopathy caused by a soft disc herniation that has failed conservative management, anterior cervical discectomy and fusion (ACDF) is widely considered the gold standard. It involves removing the herniated disc and fusing the vertebrae, providing excellent decompression and stability. Posterior laminectomy is more for myelopathy or diffuse stenosis. Laminoplasty is for multi-level stenosis. Posterior foraminotomy is for lateral foraminal stenosis. Artificial disc replacement is an alternative to fusion for select cases, but ACDF remains the most common and established approach.
Question 41:
Which of the following describes a 'stress fracture'?
Options:
- A complete fracture of a bone due to a single traumatic event.
- A fracture that occurs in a pathologically weakened bone.
- A partial or complete fracture of a bone due to repetitive submaximal loads.
- A fracture caused by direct impact to the bone.
- A fracture that is visibly open to the external environment.
Correct Answer: A partial or complete fracture of a bone due to repetitive submaximal loads.
Explanation:
A stress fracture is a partial or complete fracture of a bone that occurs due to repetitive submaximal loads or abnormal stresses on a bone that otherwise has normal elastic resistance. It is an overuse injury. A complete fracture from a single event is an acute fracture. A fracture in pathologically weakened bone is a pathological fracture. A direct impact causes a traumatic fracture. An open fracture involves a break in the skin.
Question 42:
What is the most common site for a 'boxer's fracture'?
Options:
- Distal radius.
- Fifth metacarpal neck.
- First metacarpal base.
- Navicular bone.
- Hamate bone.
Correct Answer: Fifth metacarpal neck.
Explanation:
A 'boxer's fracture' is a fracture of the neck of the fifth metacarpal bone, typically occurring from punching a hard object with a closed fist. It is often characterized by volar angulation and shortening. The distal radius is involved in Colles' fractures. First metacarpal base is a Bennett's or Rolando fracture. Navicular and hamate are carpal bones.
Question 43:
Which complication is most concerning after a high-energy pelvic fracture, particularly involving the posterior arch?
Options:
- Sciatic nerve injury.
- Deep venous thrombosis (DVT).
- Massive hemorrhage.
- Urethral injury.
- Infection.
Correct Answer: Massive hemorrhage.
Explanation:
High-energy pelvic fractures, especially those involving the posterior arch (sacroiliac joint or sacrum), are often associated with massive hemorrhage due to injury to the presacral venous plexus and internal iliac arterial branches. This can be life-threatening and requires immediate attention. While DVT, sciatic nerve injury, urethral injury (especially in males with anterior arch fractures), and infection are all possible complications, massive hemorrhage is the most immediate and critical concern.
Question 44:
What is the primary role of vitamin D in bone health?
Options:
- Directly stimulates osteoblast activity.
- Enhances calcium absorption from the gut.
- Increases phosphorus excretion by the kidneys.
- Inhibits parathyroid hormone (PTH) secretion.
- Promotes collagen synthesis in bone matrix.
Correct Answer: Enhances calcium absorption from the gut.
Explanation:
The primary role of vitamin D in bone health is to enhance the absorption of calcium and phosphate from the gastrointestinal tract. This ensures adequate mineral availability for bone mineralization. While it has some indirect effects on osteoblasts and parathyroid hormone, its most direct and significant action is on intestinal absorption. Collagen synthesis is a role of vitamin C and other factors, not directly vitamin D.
Question 45:
A patient presents with persistent foot drop and weakness in ankle dorsiflexion after a knee injury. There is also numbness in the dorsum of the foot. Which nerve is most likely injured?
Options:
- Tibial nerve.
- Sural nerve.
- Saphenous nerve.
- Common fibular (peroneal) nerve.
- Femoral nerve.
Correct Answer: Common fibular (peroneal) nerve.
Explanation:
Foot drop (inability to dorsiflex the ankle and extend the toes) and sensory loss on the dorsum of the foot are classic signs of common fibular (peroneal) nerve injury. This nerve is particularly vulnerable at the fibular head due to its superficial course. The tibial nerve controls plantarflexion. The sural and saphenous nerves are purely sensory. The femoral nerve controls knee extension and hip flexion.
Question 46:
Which condition is characterized by progressive, non-inflammatory thickening and shortening of the palmar fascia, leading to fixed flexion deformities of the fingers, most commonly the ring and small fingers?
Options:
- Trigger finger.
- Ganglion cyst.
- Carpal tunnel syndrome.
- Dupuytren's contracture.
- Flexor tenosynovitis.
Correct Answer: Dupuytren's contracture.
Explanation:
Dupuytren's contracture is a fibromatosis characterized by progressive, non-inflammatory thickening and shortening of the palmar fascia, forming nodules and cords that lead to fixed flexion deformities of the fingers, predominantly the ring and small fingers. Trigger finger is a stenosing tenosynovitis. Ganglion cysts are fluid-filled sacs. Carpal tunnel syndrome is median nerve compression. Flexor tenosynovitis is inflammation of the tendon sheath.
Question 47:
What is the primary concern for a patient with a pathological fracture?
Options:
- The severity of pain.
- The underlying systemic disease or tumor causing bone weakening.
- The need for aggressive physical therapy.
- The duration of immobilization required.
- The risk of compartment syndrome.
Correct Answer: The underlying systemic disease or tumor causing bone weakening.
Explanation:
A pathological fracture occurs through bone weakened by an underlying disease process (e.g., metastatic cancer, primary bone tumor, osteoporosis, osteomyelitis). The primary concern for a patient with a pathological fracture is to identify and manage the underlying cause of the bone weakening, as this dictates the definitive treatment strategy for the patient, not just the fracture itself. While pain and immobilization are concerns, they are secondary to addressing the root pathology. Compartment syndrome is generally not a direct risk of a pathological fracture.
Question 48:
What is the most appropriate initial management for an acute, non-displaced scaphoid fracture?
Options:
- Surgical open reduction and internal fixation.
- Casting in a long arm thumb spica cast for 6-8 weeks.
- Casting in a short arm thumb spica cast for 6-12 weeks.
- Observation with pain control.
- Immediate revascularization surgery.
Correct Answer: Casting in a short arm thumb spica cast for 6-12 weeks.
Explanation:
For an acute, non-displaced scaphoid fracture, the most appropriate initial management is immobilization in a short arm thumb spica cast. Due to the high risk of nonunion and avascular necrosis, prolonged immobilization (typically 6-12 weeks, sometimes longer) is often required. Surgical fixation is considered for displaced fractures, proximal pole fractures, or delayed unions. Observation alone is inappropriate, and revascularization surgery is not an initial step for a non-displaced fracture.
Question 49:
Which of the following conditions is characterized by anterior knee pain, particularly aggravated by ascending/descending stairs or prolonged sitting, and often associated with crepitus?
Options:
- Patellar tendinopathy (Jumper's knee).
- Osgood-Schlatter disease.
- Patellofemoral pain syndrome (PFPS).
- Medial plica syndrome.
- IT band syndrome.
Correct Answer: Patellofemoral pain syndrome (PFPS).
Explanation:
Patellofemoral pain syndrome (PFPS), also known as 'runner's knee,' is characterized by anterior knee pain, often worse with activities that load the patellofemoral joint (stairs, squatting, prolonged sitting - 'theater sign'). Crepitus is also a common finding. Patellar tendinopathy causes localized pain at the inferior pole of the patella. Osgood-Schlatter disease affects adolescents with pain at the tibial tubercle. Medial plica syndrome has specific medial knee pain and snapping. IT band syndrome causes lateral knee pain.
Question 50:
In the context of the spine, what is the 'Hangman's fracture'?
Options:
- A fracture of the odontoid process.
- A bilateral pedicle fracture of C2.
- A burst fracture of C1.
- A fracture of the body of C7.
- An avulsion fracture of the spinous process of C6.
Correct Answer: A bilateral pedicle fracture of C2.
Explanation:
A 'Hangman's fracture' is a traumatic spondylolisthesis of the axis (C2), specifically a bilateral fracture of the C2 pars interarticularis (pedicles). It typically occurs from hyperextension and distraction injuries. Odontoid fractures are Type I, II, or III. A burst fracture of C1 is a Jefferson fracture. The other options describe different, less specific cervical spine injuries.
Question 51:
What is the most common presenting symptom of a patient with a stress fracture of the metatarsals?
Options:
- Acute, sharp pain after a single traumatic event.
- Gradual onset of forefoot pain, worse with activity, relieved by rest.
- Sudden numbness and tingling in the toes.
- Visible deformity of the foot.
- Systemic fever and chills.
Correct Answer: Gradual onset of forefoot pain, worse with activity, relieved by rest.
Explanation:
Stress fractures, including those of the metatarsals, are characterized by a gradual onset of localized pain that worsens with activity (e.g., running, prolonged walking) and is relieved by rest. There is typically no acute traumatic event, and visible deformity or systemic symptoms are usually absent. Acute, sharp pain after trauma suggests an acute fracture. Numbness/tingling suggests nerve involvement. Fever/chills suggest infection.
Question 52:
Which of the following is a classic indication for surgical repair of a full-thickness rotator cuff tear?
Options:
- Chronic, asymptomatic tear in an elderly patient.
- Partial-thickness tear with minimal pain.
- Small, full-thickness tear in a highly active, younger patient with functional deficits.
- Large, irreparable tear in a patient with glenohumeral arthritis.
- Any rotator cuff tear, regardless of symptoms.
Correct Answer: Small, full-thickness tear in a highly active, younger patient with functional deficits.
Explanation:
Surgical repair of a full-thickness rotator cuff tear is typically indicated for highly active, younger patients (under 60-65 years) who experience significant pain, weakness, or functional deficits that have failed conservative management, even for smaller tears, to prevent progression and restore function. Asymptomatic tears, partial tears with minimal symptoms, or irreparable tears in patients with advanced arthritis are generally managed conservatively or with alternative procedures (e.g., reverse total shoulder arthroplasty for cuff tear arthropathy).
Question 53:
What is the primary goal of surgical treatment for hallux valgus (bunion deformity)?
Options:
- Cosmetic improvement of foot appearance.
- Complete elimination of pain and restoration of normal foot mechanics.
- Correction of the intermetatarsal angle and hallux valgus angle.
- Fusion of the first metatarsophalangeal (MTP) joint.
- Amputation of the hallux.
Correct Answer: Correction of the intermetatarsal angle and hallux valgus angle.
Explanation:
The primary goal of surgical treatment for hallux valgus is to correct the underlying bony deformity, specifically the increased intermetatarsal angle (IMA) between the first and second metatarsals, and the increased hallux valgus angle (HVA). This bony realignment aims to relieve pain, improve foot mechanics, and prevent recurrence. While pain relief is a significant outcome, restoring 'normal' mechanics can be challenging. Fusion is reserved for severe arthritis or failed previous surgeries. Cosmetic improvement is a secondary benefit, not the primary goal. Amputation is not a standard treatment.
Question 54:
What is the primary role of the anterior cruciate ligament (ACL) in the knee joint?
Options:
- Preventing varus stress.
- Preventing valgus stress.
- Preventing anterior translation of the tibia on the femur.
- Preventing posterior translation of the tibia on the femur.
- Preventing excessive knee hyperextension.
Correct Answer: Preventing anterior translation of the tibia on the femur.
Explanation:
The anterior cruciate ligament (ACL) is the primary restraint to anterior translation of the tibia on the femur and also limits internal and external rotation of the tibia. It is crucial for knee stability, especially during rotational and pivoting movements. The medial collateral ligament (MCL) prevents valgus stress. The lateral collateral ligament (LCL) prevents varus stress. The posterior cruciate ligament (PCL) prevents posterior translation of the tibia. Hyperextension is limited by various capsular and ligamentous structures.
Question 55:
A 5-year-old child sustains a low-energy buckle fracture (torus fracture) of the distal radius. What is the most appropriate treatment?
Options:
- Open reduction and internal fixation.
- Long arm cast for 6 weeks.
- Short arm cast or removable wrist splint for 3-4 weeks.
- Observation only with pain medication.
- Percutaneous pinning.
Correct Answer: Short arm cast or removable wrist splint for 3-4 weeks.
Explanation:
A buckle (torus) fracture is a stable, incomplete fracture of the metaphysis common in children, characterized by cortical buckling without a true fracture line. These are very stable and heal well with minimal immobilization. A short arm cast or removable wrist splint for 3-4 weeks is typically sufficient. Open reduction and internal fixation, long arm casts, or percutaneous pinning are overly aggressive for such a stable injury. Observation only is insufficient for adequate healing and pain control.
Question 56:
Which of the following conditions is a common cause of chronic anterior shin pain in athletes, often termed 'shin splints,' that is distinct from a stress fracture?
Options:
- Acute compartment syndrome.
- Medial tibial stress syndrome (MTSS).
- Peroneal tendinopathy.
- Anterior cruciate ligament tear.
- Achilles tendinopathy.
Correct Answer: Medial tibial stress syndrome (MTSS).
Explanation:
Medial tibial stress syndrome (MTSS), commonly known as 'shin splints,' is a common overuse injury in athletes causing chronic anterior or anteromedial shin pain. It is distinct from a stress fracture (though it can progress to one) and compartment syndrome. Acute compartment syndrome is an emergency with severe pain, swelling, and neurovascular compromise. Peroneal tendinopathy causes lateral ankle pain. ACL tears affect the knee. Achilles tendinopathy causes posterior heel/calf pain.
Question 57:
What is the primary principle of managing an irreducible pediatric forearm fracture?
Options:
- Always attempt repeated closed reduction maneuvers.
- Perform open reduction and internal fixation to restore anatomy.
- Apply traction for several days before attempting reduction.
- Immobilize in a cast in the existing position.
- Administer strong sedatives and observe for spontaneous reduction.
Correct Answer: Perform open reduction and internal fixation to restore anatomy.
Explanation:
For an irreducible pediatric forearm fracture (meaning closed reduction attempts have failed or are impossible), the primary principle is to perform open reduction and internal fixation. This is necessary to restore proper alignment and rotation to prevent malunion, which can severely impact forearm function. Repeated forceful closed reductions can cause more soft tissue damage. Traction or immobilization in the irreducible position are not acceptable long-term solutions, as they will lead to significant functional impairment.
Question 58:
What is the characteristic deformity observed in a Monteggia fracture-dislocation?
Options:
- Fracture of the distal radius with dorsal displacement.
- Fracture of the ulna shaft with dislocation of the radial head.
- Fracture of the radial shaft with dislocation of the distal radioulnar joint.
- Fracture of both radius and ulna shafts.
- Fracture of the olecranon with posterior elbow dislocation.
Correct Answer: Fracture of the ulna shaft with dislocation of the radial head.
Explanation:
A Monteggia fracture-dislocation is characterized by a fracture of the ulna shaft (often in the proximal or mid-third) associated with a dislocation of the radial head. The most common type is an anterior dislocation of the radial head with an anteriorly angulated ulnar fracture (Bado Type I). A Galeazzi fracture-dislocation involves a radial shaft fracture with distal radioulnar joint dislocation. Fracture of both radius and ulna is a both-bone forearm fracture. Distal radius fracture is a Colles' or Smith's fracture. Olecranon fracture with posterior elbow dislocation is a variant of terrible triad or simple dislocation.