I85PREP
⌘ K
Arab Board Orthopedic Surgery Final study materials
Arab Board Orthopedic Surgery Final study resources

Arab Board Orthopedic Surgery Final practice questions

One question at a time. Build your Arab Board Orthopedic Surgery Final understanding.

First 50 of 200 questions. Each one lists the choices, the correct answer, and an explanation. The checker at the top of this page saves progress in this browser when it is available.

Continue in the practice tool above to load more questions, 50 at a time.

Question 1Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

Which structure passes through the lesser sciatic foramen?

  1. Sciatic nerve
  2. Pudendal nerve Correct answer.
  3. Obturator internus tendon
  4. Superior gluteal nerve

Explanation

The lesser sciatic foramen is bounded by the sacrotuberous and sacrospinous ligaments and the ischial spine/lesser ischial notch. The pudendal nerve and internal pudendal vessels re-enter the pelvis through it. The obturator internus tendon turns within it but exits via the greater foramen.

Question 2Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

The blood supply to the femoral head in an adult is derived predominantly from which vessel?

  1. Artery of the ligamentum teres
  2. Inferior gluteal artery
  3. Medial circumflex femoral artery Correct answer.
  4. Lateral circumflex femoral artery

Explanation

In adults the medial circumflex femoral artery, via its retinacular branches, supplies most of the femoral head. The artery of the ligamentum teres contributes only a small variable amount. Disruption of the medial circumflex branches explains the high risk of avascular necrosis after displaced femoral neck fracture.

Question 3Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

Which nerve is most at risk during a direct lateral (Hardinge) approach to the hip?

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

Explanation

The superior gluteal nerve runs between gluteus medius and minimus and is vulnerable when the split is carried too far proximally above the greater trochanter. Injury produces a Trendelenburg gait. The safe zone is generally within 5 cm of the tip of the greater trochanter.

Question 4Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

According to the AO classification, a fracture with complete loss of cortical contact between fragments after reduction is best described as:

  1. Type A
  2. Type D
  3. Type C Correct answer.
  4. Type B

Explanation

In the AO/OTA system, type A fractures are extra-articular with simple patterns, type B are partial articular, and type C are complete articular or completely unstable fractures with no cortical contact after reduction. Complete displacement with loss of contact defines the most unstable category.

Question 5Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

Which biomechanical principle underlies the use of a lag screw for interfragmentary compression?

  1. It converts shear force into compressive force across the fracture Correct answer.
  2. It increases the bending stiffness of the plate
  3. It eliminates the need for cortical contact
  4. It converts compressive force into shear force across the fracture

Explanation

A lag screw achieves interfragmentary compression by engaging only the far cortex, drawing the fragments together. This converts shear forces at the fracture into compressive forces, which bone tolerates well. Absolute stability with primary healing is the goal.

Question 6Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

In the tension band principle, a tension band wire applied to the patella converts which force into compression at the articular surface?

  1. Shear force from the tibiofemoral joint
  2. Compressive force from the quadriceps
  3. Tensile force from the extensor mechanism Correct answer.
  4. Torsional force from the hamstrings

Explanation

The tension band converts tensile forces acting on the convex (anterior) surface into compression at the concave (articular) surface during flexion. This is why the wire and Kirschner wires are placed anteriorly. The principle requires an intact anterior cortex to buttress compression.

Question 7Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

Wolff's law describes which relationship?

  1. Bone remodels in response to the mechanical loads placed on it Correct answer.
  2. Tendon healing follows a predictable inflammatory sequence
  3. Bone resorption is independent of mechanical stress
  4. Cartilage thickness is determined by joint congruity

Explanation

Wolff's law states that bone adapts its architecture to the loads applied to it, depositing where stress is high and resorbing where it is low. This underlies stress shielding around stiff implants and the benefit of early controlled loading.

Question 8Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

Which cell type is primarily responsible for bone resorption?

  1. Osteoclast Correct answer.
  2. Osteoblast
  3. Chondrocyte
  4. Osteocyte

Explanation

Osteoclasts are multinucleated cells of hematopoietic (monocyte/macrophage) lineage that resorb bone via a ruffled border and proton pump. Osteoblasts form bone and osteocytes are mechanosensors within the matrix.

Question 9Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

A patient has a fracture through bone that was previously abnormal due to Paget disease. This is best termed:

  1. A fatigue fracture
  2. A pathologic fracture Correct answer.
  3. A greenstick fracture
  4. A stress fracture

Explanation

A pathologic fracture occurs through bone weakened by an underlying disease process such as tumor, infection, or metabolic bone disease. Fatigue and stress fractures occur through repetitive loading of otherwise normal bone.

Question 10Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

Which of the following best defines the moment arm of a muscle force about a joint?

  1. The cross-sectional area of the muscle belly
  2. The perpendicular distance from the joint axis to the line of action of the force Correct answer.
  3. The total length of the muscle from origin to insertion
  4. The angle between the muscle and the long axis of the bone

Explanation

The moment (torque) equals force multiplied by the perpendicular distance from the axis of rotation to the line of action of the force. This perpendicular distance is the moment arm. It varies with joint angle, which is why torque-generating capacity changes through range of motion.

Question 11Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

In a three-point bending model of a long bone, where does the highest tensile stress occur?

  1. On the convex side of the bone Correct answer.
  2. At the neutral axis
  3. On the concave side of the bone
  4. Uniformly across the cortex

Explanation

Bending produces compression on the concave side and tension on the convex side, with a neutral axis between them. Bone fails in tension before compression, so the convex cortex is the site of crack initiation. This is why transverse fractures often begin on the tension side.

Question 12Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

The carrying angle of the elbow in a normal adult is approximately:

  1. 5-15 degrees of valgus Correct answer.
  2. 30-40 degrees of valgus
  3. 20-30 degrees of varus
  4. 0-5 degrees of valgus

Explanation

The normal carrying angle is about 5-15 degrees of valgus, greater in women and decreasing with age. It results from the medial flange of the trochlea. Loss of this angle after supracondylar fracture indicates malunion (cubitus varus).

Question 13Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

Which structure is most commonly injured in an anterior shoulder dislocation?

  1. Axillary nerve Correct answer.
  2. Radial nerve
  3. Suprascapular nerve
  4. Long thoracic nerve

Explanation

The axillary nerve winds around the surgical neck of the humerus and is the nerve most frequently injured in anterior shoulder dislocation. It should be tested by deltoid contraction and sensation over the lateral shoulder. Most injuries are neurapraxic and recover.

Question 14Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

The anterior cruciate ligament primarily resists which motion?

  1. Anterior translation of the tibia on the femur Correct answer.
  2. Internal rotation of the femur on the tibia
  3. Varus angulation of the knee
  4. Posterior translation of the tibia on the femur

Explanation

The ACL's main function is to resist anterior tibial translation and to provide rotational stability. The posterior cruciate ligament resists posterior translation. The Lachman test assesses ACL integrity by detecting abnormal anterior translation.

Question 15Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

In the classification of open fractures, a Gustilo-Anderson type IIIB injury is characterized by:

  1. Inadequate soft tissue coverage requiring a flap Correct answer.
  2. Adequate soft tissue coverage despite extensive injury
  3. A wound less than 1 cm with minimal contamination
  4. A wound greater than 10 cm with extensive soft tissue damage

Explanation

Gustilo-Anderson IIIB denotes extensive soft tissue loss with periosteal stripping and inadequate soft tissue coverage, requiring a local or free flap. Type IIIC adds a vascular injury requiring repair. Types I and II involve progressively larger wounds with adequate coverage.

Question 16Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

Which of the following is the primary determinant of the ultimate tensile strength of a tendon graft used for ligament reconstruction?

  1. Cross-sectional area of the graft Correct answer.
  2. Suture type used for fixation
  3. Donor age of the patient
  4. Length of the graft

Explanation

Tensile strength is proportional to the cross-sectional area of the graft (stress = force/area). Larger grafts have greater load to failure. Length and fixation method affect other properties but not the intrinsic material strength.

Question 17Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

The blood supply to the scaphoid is predominantly via which artery, entering at which pole?

  1. Dorsal carpal branch of the radial artery entering proximally Correct answer.
  2. Interosseous branch of the anterior interosseous artery entering proximally
  3. Volar branch of the ulnar artery entering proximally
  4. Dorsal carpal branch of the radial artery entering distally

Explanation

The scaphoid receives its blood supply mainly from the dorsal carpal branch of the radial artery, entering through the dorsal ridge near the waist and supplying the proximal pole retrogradely. This explains the high risk of avascular necrosis in proximal pole fractures.

Question 18Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

Which structure forms the medial boundary of the femoral triangle?

  1. Adductor longus Correct answer.
  2. Sartorius
  3. Inguinal ligament
  4. Pectineus

Explanation

The femoral triangle is bounded laterally by the sartorius, medially by the adductor longus, and superiorly by the inguinal ligament. Its floor is formed by iliopsoas, pectineus, and adductor longus. The femoral vessels and nerve lie within it.

Question 19Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

In the Salter-Harris classification of physeal fractures, a type III injury involves:

  1. The physis and metaphysis
  2. The physis and epiphysis Correct answer.
  3. The physis, metaphysis, and epiphysis
  4. The physis alone

Explanation

Salter-Harris III fractures extend through the physis and out through the epiphysis into the joint. Type I involves the physis alone, type II the physis and metaphysis, and type IV both metaphysis and epiphysis. Type V is a crush injury of the physis.

Question 20Basic Sciences of Orthopedics (anatomy, biomechanics, pathology, physiology)

Which of the following best explains the phenomenon of stress shielding around a stiff intramedullary implant?

  1. Increased load transfer through the implant reduces load on adjacent bone, causing resorption Correct answer.
  2. The implant generates heat that causes bone necrosis
  3. The implant prevents periosteal blood flow, causing ischemia
  4. Corrosion products directly dissolve the cortex

Explanation

A stiff implant shares load with the bone, reducing the strain experienced by the bone according to Wolff's law. Reduced mechanical stimulus leads to cortical resorption and thinning. This is why implants with a modulus closer to bone are favored.

Question 21Trauma and Fracture Management

A 25-year-old man has a closed tibial shaft fracture treated with an intramedullary nail. On the second postoperative day he develops calf pain, calf swelling and tachycardia. Which is the most appropriate next step in management?

  1. Urgent venous duplex ultrasound of the leg Correct answer.
  2. Immediate prophylactic IVC filter insertion
  3. Repeat radiographs of the tibia
  4. Reassurance and elevation alone

Explanation

Postoperative calf pain, swelling and tachycardia after lower limb fracture surgery raise suspicion of deep vein thrombosis, and compression duplex ultrasound is the diagnostic test of choice. Confirmation guides anticoagulation. Prophylaxis alone does not exclude an established thrombus.

Question 22Trauma and Fracture Management

Which finding best distinguishes compartment syndrome of the leg from other causes of postoperative pain?

  1. Absent distal pulses with pallor of the foot
  2. Reduced sensation confined to the first web space
  3. Elevated creatine kinase level in the serum
  4. Pain out of proportion to the injury, worsened by passive stretch of the compartment muscles Correct answer.

Explanation

The earliest and most reliable clinical sign of compartment syndrome is pain disproportionate to the injury that is aggravated by passive stretch of the muscles within the affected compartment. Pulselessness and pallor are late findings.

Question 23Trauma and Fracture Management

A 70-year-old woman sustains a minimally displaced femoral neck fracture and is independently mobile. Which treatment offers the lowest rate of reoperation?

  1. Conservative management with traction
  2. Cannulated screw fixation
  3. Total hip arthroplasty Correct answer.
  4. Dynamic hip screw

Explanation

In displaced or minimally displaced intracapsular femoral neck fractures in older patients, arthroplasty reduces the risk of reoperation compared with internal fixation. Total hip arthroplasty is preferred in previously independent patients because it gives better function and lower revision rates than hemiarthroplasty.

Question 24Trauma and Fracture Management

Which nerve is most commonly injured during surgical fixation of a distal humerus fracture?

  1. Ulnar nerve Correct answer.
  2. Musculocutaneous nerve
  3. Median nerve
  4. Radial nerve

Explanation

The ulnar nerve lies in the cubital tunnel posterior to the medial epicondyle and is at greatest risk during distal humerus surgery, particularly with medial plate placement. It is often formally identified and protected or transposed.

Question 25Trauma and Fracture Management

A 30-year-old man has an open tibial fracture with a 5 cm wound and extensive periosteal stripping after a motorcycle crash. According to the Gustilo-Anderson classification, which grade applies?

  1. IIIA Correct answer.
  2. IIIB
  3. I
  4. II

Explanation

Gustilo-Anderson type IIIA describes an open fracture with extensive soft tissue laceration and adequate bone coverage despite high-energy injury. Type IIIB requires a flap for soft tissue coverage, and type IIIC involves arterial injury requiring repair.

Question 26Trauma and Fracture Management

Which is the most appropriate initial antibiotic regimen for a Gustilo-Anderson type III open tibial fracture?

  1. No antibiotics until intraoperative cultures are taken
  2. A first-generation cephalosporin plus an aminoglycoside Correct answer.
  3. Vancomycin alone
  4. A first-generation cephalosporin alone

Explanation

High-grade open fractures require broad-spectrum cover with a cephalosporin plus an aminoglycoside to cover gram-negative organisms. Antipseudomonal cover is added for farm or soil contamination. Antibiotics should be given as soon as possible.

Question 27Trauma and Fracture Management

A 45-year-old man has a displaced midshaft clavicle fracture with 100% displacement and skin tenting. What is the most appropriate management?

  1. Immediate shoulder manipulation
  2. Open reduction and internal fixation Correct answer.
  3. Sling immobilization alone
  4. Figure-of-eight bandage

Explanation

Absolute indications for surgical fixation of clavicle fractures include skin tenting threatening to perforate, open fracture, and neurovascular compromise. Operative fixation restores alignment and prevents skin breakdown.

Question 28Trauma and Fracture Management

Which radiographic view is most useful for detecting a posterior shoulder dislocation?

  1. Weight-bearing AP view
  2. Transthoracic lateral view
  3. Axillary or scapular Y view Correct answer.
  4. Standard AP view alone

Explanation

Posterior shoulder dislocation is easily missed on an AP radiograph because the humeral head may appear normally aligned. The axillary or scapular Y view demonstrates the posterior displacement. A 'light bulb' sign on AP should prompt these views.

Question 29Trauma and Fracture Management

A 35-year-old man has an isolated, minimally displaced radial head fracture with a mechanical block to forearm rotation. Which management is most appropriate?

  1. Open reduction and internal fixation or radial head replacement
  2. Long arm cast for six weeks
  3. Collar and cuff with early mobilization
  4. Excision of the radial head Correct answer.

Explanation

A mechanical block to rotation with a radial head fracture is an indication for surgery to restore motion. Fixation is preferred when feasible; replacement is used for comminuted fractures not amenable to fixation.

Question 30Trauma and Fracture Management

Which finding on a pelvic radiograph indicates an unstable pelvic ring injury requiring urgent stabilization?

  1. Isolated pubic ramus fracture
  2. Isolated iliac wing fracture
  3. Vertical shear displacement of the hemipelvis Correct answer.
  4. Avulsion of the anterior superior iliac spine

Explanation

Vertical shear displacement indicates a mechanically unstable pelvic ring injury, often with major hemorrhage, and requires urgent stabilization. Isolated fractures of the rami or iliac wing are typically stable.

Question 31Trauma and Fracture Management

A patient with a pelvic ring fracture is hypotensive despite fluid resuscitation. Which is the most appropriate first step in hemorrhage control?

  1. Application of a pelvic binder and angiography with embolization Correct answer.
  2. Immediate laparotomy
  3. CT scan before any intervention
  4. Immediate external fixation alone

Explanation

In hemodynamically unstable pelvic fractures, a pelvic binder is applied to reduce pelvic volume and stabilize the ring, followed by angiography and embolization if bleeding persists. This sequence addresses the most common source of hemorrhage, the pelvic venous plexus and arterial branches.

Question 32Trauma and Fracture Management

Which is the most appropriate initial management of a displaced supracondylar humerus fracture in a child with an absent radial pulse but a well-perfused hand?

  1. Above-elbow amputation
  2. Observation with a backslab and repeat examination in 24 hours
  3. Urgent closed reduction and percutaneous pinning Correct answer.
  4. Immediate brachial artery exploration

Explanation

A pulseless but well-perfused hand in a displaced supracondylar fracture is usually due to brachial artery spasm or kinking, and urgent reduction and pinning typically restores flow. Vascular exploration is reserved for a poorly perfused hand after reduction.

Question 33Trauma and Fracture Management

Which nerve is most commonly injured in a pediatric supracondylar humerus fracture with posterolateral displacement?

  1. Ulnar nerve
  2. Axillary nerve
  3. Radial nerve
  4. Median nerve Correct answer.

Explanation

Posterolateral displacement of the distal fragment places the median nerve at greatest risk, particularly the anterior interosseous branch. Posteromedial displacement endangers the radial nerve.

Question 34Trauma and Fracture Management

A 60-year-old man has a closed distal femoral shaft fracture. Which is the most appropriate definitive treatment?

  1. Hip spica
  2. Cast immobilization
  3. Intramedullary nailing Correct answer.
  4. Traction for eight weeks

Explanation

Intramedullary nailing provides stable fixation and early mobilization for distal femoral shaft fractures. It is the treatment of choice for most adult femoral shaft fractures.

Question 35Trauma and Fracture Management

Which is the most appropriate management of a displaced femoral shaft fracture in a hemodynamically unstable polytrauma patient?

  1. Immediate intramedullary nailing regardless of physiology
  2. Traction for six weeks
  3. Amputation
  4. Damage control with temporary external fixation followed by nailing when stable Correct answer.

Explanation

In unstable polytrauma patients, damage control orthopaedics uses temporary external fixation to stabilize the fracture while minimizing physiological insult, followed by definitive nailing once the patient is resuscitated. This reduces the risk of fat embolism and ARDS.

Question 36Trauma and Fracture Management

Which is the most reliable clinical test for posterior cruciate ligament integrity?

  1. Posterior drawer test Correct answer.
  2. McMurray test
  3. Anterior drawer test
  4. Lachman test

Explanation

The posterior drawer test directly assesses posterior translation of the tibia relative to the femur and is the most reliable clinical test for PCL integrity. The posterior sag sign is a useful adjunct.

Question 37Trauma and Fracture Management

A 25-year-old man has a tibial plateau fracture with depression of the lateral condyle. Which is the most appropriate management?

  1. Open reduction and internal fixation with elevation of the depressed fragment Correct answer.
  2. Cast immobilization
  3. Traction alone
  4. Immediate total knee arthroplasty

Explanation

Displaced tibial plateau fractures with articular depression require anatomic reduction and stable fixation to restore the joint surface and prevent post-traumatic arthritis. Bone graft or substitute may be needed to support the elevated fragment.

Question 38Trauma and Fracture Management

Which is the most appropriate initial management of an open ankle fracture with gross contamination?

  1. Immediate internal fixation without debridement
  2. Urgent irrigation and debridement with antibiotics and temporary stabilization Correct answer.
  3. Cast application and outpatient follow-up
  4. Delayed debridement after 24 hours

Explanation

Open fractures require urgent irrigation and debridement, intravenous antibiotics, and stabilization. Internal fixation may be performed after adequate debridement but should not precede it in grossly contaminated wounds.

Question 39Trauma and Fracture Management

Which finding on examination of the ankle suggests a syndesmotic injury in a patient with an ankle sprain?

  1. Positive anterior drawer with a firm endpoint
  2. Pain on squeeze test and external rotation stress Correct answer.
  3. Pain localized to the base of the fifth metatarsal
  4. Tenderness over the lateral malleolus only

Explanation

The squeeze test and external rotation stress test are clinical indicators of distal tibiofibular syndesmotic injury. These injuries require specific imaging and often surgical stabilization.

Question 40Trauma and Fracture Management

Which is the most appropriate management of a displaced intra-articular calcaneal fracture with severe soft tissue swelling?

  1. Immediate open reduction and internal fixation on the day of injury
  2. Delay surgery until soft tissue swelling resolves, then open reduction and internal fixation Correct answer.
  3. Immediate amputation
  4. Immediate subtalar arthrodesis

Explanation

Calcaneal fractures are associated with significant soft tissue swelling, and surgery is delayed until the wrinkle sign is positive to reduce wound complications. Immediate fixation risks wound breakdown and infection.

Question 41Trauma and Fracture Management

A 30-year-old man has a scaphoid waist fracture with no displacement. Which is the most appropriate management?

  1. Immediate open reduction and screw fixation
  2. Excision of the proximal pole
  3. Immobilization in a short arm thumb spica cast with repeat radiographs Correct answer.
  4. Corticosteroid injection

Explanation

Undisplaced scaphoid waist fractures are treated nonoperatively with a thumb spica cast and repeat imaging to confirm healing, because of the risk of nonunion and avascular necrosis. Surgery is reserved for displacement or proximal pole fractures.

Question 42Trauma and Fracture Management

Which is the most appropriate initial management of a Bennett fracture of the thumb base?

  1. Excision of the trapezium
  2. Closed reduction and percutaneous pinning Correct answer.
  3. Cast immobilization alone
  4. Traction

Explanation

Bennett fractures are intra-articular and unstable due to the pull of the abductor pollicis longus, so closed reduction and percutaneous pinning are usually required for anatomic reduction. Nonoperative treatment leads to malunion and arthritis.

Question 43Trauma and Fracture Management

Which is the most appropriate management of a pediatric both-bone forearm fracture with acceptable alignment?

  1. Flexible intramedullary nailing in all cases
  2. Traction for six weeks
  3. Immediate open reduction and plating
  4. Above-elbow cast with clinical and radiographic follow-up Correct answer.

Explanation

Most pediatric both-bone forearm fractures with acceptable alignment can be treated with an above-elbow cast, relying on remodeling potential. Operative treatment is reserved for unacceptable alignment, open fractures, or unstable patterns.

Question 44Trauma and Fracture Management

Which is the most appropriate management of an open book pelvic fracture with hemodynamic instability?

  1. Application of a pelvic binder and early external fixation Correct answer.
  2. Immediate hip spica
  3. Delayed angiography after 24 hours
  4. Observation with bed rest

Explanation

Open book pelvic fractures increase pelvic volume and can cause massive hemorrhage, so a binder and external fixation restore stability and reduce bleeding. Angiography is added if bleeding persists.

Question 45Trauma and Fracture Management

Which is the most appropriate management of a patellar fracture with a disrupted extensor mechanism?

  1. Cast immobilization alone
  2. Open reduction and tension band wiring Correct answer.
  3. Patellectomy
  4. Traction

Explanation

Disruption of the extensor mechanism with a displaced patellar fracture requires surgical repair to restore active knee extension. Tension band wiring is used for transverse fractures.

Question 46Trauma and Fracture Management

A 28-year-old motorcyclist has a closed midshaft femoral fracture. He is awake, alert, and has a GCS of 15 with no other injuries. Which finding is the strongest indication for immediate intramedullary nailing rather than damage-control external fixation?

  1. A fracture with a small puncture wound over the thigh
  2. A stable hemodynamic profile without signs of shock Correct answer.
  3. A concomitant ipsilateral tibial shaft fracture
  4. A femoral shaft fracture with 3 cm of shortening

Explanation

Early definitive intramedullary nailing is favored in an isolated femoral shaft fracture when the patient is hemodynamically stable, since this reduces pulmonary complications and length of stay. Damage-control external fixation is reserved for physiologically unstable or severely polytraumatized patients. The decision hinges on physiology, not on the fracture pattern alone.

Question 47Trauma and Fracture Management

A 70-year-old woman sustains a fragility fracture of the distal radius with dorsal comminution and intra-articular extension. Which factor most strongly predicts loss of reduction after closed reduction and cast application?

  1. Dorsal comminution and intra-articular extension Correct answer.
  2. A fracture line confined to the metaphysis
  3. The patient's dominant hand involvement
  4. Presence of a small volar lip fragment

Explanation

Dorsal comminution with intra-articular extension is a well-recognized predictor of secondary displacement after closed treatment because the dorsal cortex cannot buttress the distal fragment. Such patterns often warrant operative fixation. Dominance and small volar fragments do not reliably predict collapse.

Question 48Trauma and Fracture Management

A 24-year-old man has an isolated posterior malleolus fracture involving 30% of the articular surface on axial CT with a step-off. Which is the most appropriate management?

  1. Closed reduction and percutaneous pinning without fixation
  2. Open reduction and internal fixation Correct answer.
  3. Ankle brace with early weight bearing
  4. Below-knee cast for six weeks

Explanation

Posterior malleolar fractures with a substantial articular fragment and step-off are best treated with anatomic reduction and internal fixation to restore the tibiotalar joint and syndesmotic stability. Nonoperative treatment risks post-traumatic arthritis and instability. Fixation can be achieved through an anterolateral or posterolateral approach.

Question 49Trauma and Fracture Management

A 40-year-old man has a both-column acetabular fracture with medial displacement of the femoral head and no associated hip dislocation. Which is the most appropriate initial step?

  1. Immediate total hip arthroplasty
  2. Skeletal traction to maintain the femoral head position Correct answer.
  3. Early weight bearing to promote fracture consolidation
  4. Non-weight-bearing mobilization without traction

Explanation

Skeletal traction is used in both-column acetabular fractures to maintain the femoral head out to length and prevent further medial migration while awaiting definitive surgery. It is a temporizing measure, not definitive treatment. Definitive management is usually open reduction and internal fixation.

Question 50Trauma and Fracture Management

A 55-year-old man has a displaced transverse patella fracture with a 3 cm gap and inability to actively extend the knee. Which is the most appropriate management?

  1. Cylinder cast for eight weeks
  2. Open reduction and tension-band wiring Correct answer.
  3. Patellectomy with quadriceps repair
  4. Arthroscopic debridement alone

Explanation

A displaced patella fracture with a disrupted extensor mechanism requires operative restoration of the extensor mechanism, typically with tension-band wiring. Nonoperative treatment would result in extensor lag and weakness. Patellectomy is reserved for unreconstructable comminution.