Menu

2. Trauma MCQs

Practice Set 261 of 640

This practice set contains high-yield board review questions covering key concepts in 2. Trauma. Each clinical scenario is designed to test your diagnostic and management skills relevant to this subspecialty.

Question 5201

Topic: 2. Trauma

A 25-year-old male sustains an acute tibia fracture and subsequently develops compartment syndrome. The surgeon performs a standard two-incision, four-compartment fasciotomy. The medial incision is placed too anteriorly, just behind the medial tibial crest, and fails to adequately release a specific compartment. Which structures are at highest risk of ischemic contracture?

. Tibialis anterior, extensor hallucis longus, extensor digitorum longus
. Peroneus longus, peroneus brevis
. Gastrocnemius, soleus
. Tibialis posterior, flexor hallucis longus, flexor digitorum longus
. Popliteus, plantaris

Correct Answer & Explanation

. Tibialis posterior, flexor hallucis longus, flexor digitorum longus

Explanation

The deep posterior compartment is the most frequently missed or inadequately released compartment during a fasciotomy for leg compartment syndrome, especially if the medial incision is not placed far enough posteriorly (it should be 2 cm posterior to the posteromedial border of the tibia). Failure to release it jeopardizes its contents: the tibialis posterior, flexor hallucis longus, and flexor digitorum longus muscles, leading to claw toe and equinovarus contractures.

Question 5202

Topic: 2. Trauma

A trauma patient is evaluated for an acetabular fracture. The obturator oblique radiographic view reveals a classic 'spur sign.' This radiographic finding is pathognomonic for which type of acetabular fracture according to the Letournel and Judet classification?

. Transverse fracture
. T-type fracture
. Associated both column fracture
. Anterior column with posterior hemitransverse fracture
. Isolated posterior column fracture

Correct Answer & Explanation

. Associated both column fracture

Explanation

The 'spur sign' on an obturator oblique radiograph represents the lowest limit of the intact portion of the ilium (the strut of bone above the acetabular roof) that remains attached to the axial skeleton while the entire articular surface (both anterior and posterior columns) is detached and medially displaced. It is pathognomonic for an associated both-column fracture.

Question 5203

Topic: 2. Trauma

A 32-year-old male sustains a closed, transverse midshaft humerus fracture. His initial neurologic exam in the emergency department is intact. Following closed reduction and application of a coaptation splint, he is unable to actively extend his wrist or fingers. What is the most appropriate next step in management?

. Observation and electromyography at 3 weeks
. Immediate surgical exploration and ORIF
. Ultrasound of the radial nerve
. Switch to a functional fracture brace
. Removal of the splint and passive stretching exercises

Correct Answer & Explanation

. Immediate surgical exploration and ORIF

Explanation

A secondary (iatrogenic) radial nerve palsy that develops after closed reduction or manipulation of a humeral shaft fracture is an absolute indication for surgical exploration. This is required to ensure the nerve is not entrapped or lacerated within the fracture site.

Question 5204

Topic: 2. Trauma

A 24-year-old male presents with a symptomatic proximal pole scaphoid nonunion. MRI demonstrates avascular necrosis (AVN) of the proximal pole fragment. Which of the following is the most appropriate surgical management to maximize the chance of union?

. Volar wedge graft and rigid K-wire fixation
. Proximal row carpectomy
. Four-corner fusion
. Vascularized medial femoral condyle bone graft
. 1,2 intercompartmental supraretinacular artery (1,2 ICSRA) graft

Correct Answer & Explanation

. Vascularized medial femoral condyle bone graft

Explanation

Proximal pole scaphoid nonunions complicated by avascular necrosis require a vascularized bone graft for optimal healing. The free vascularized medial femoral condyle (MFC) graft provides robust structural support and reliable blood supply, demonstrating significantly higher union rates than pedicled grafts for AVN.

Question 5205

Topic: 2. Trauma

Which muscles are located in the deep volar compartment of the forearm and are considered the most susceptible to irreversible ischemic necrosis in an unrecognized compartment syndrome?

. Flexor carpi radialis and pronator teres
. Flexor digitorum superficialis and palmaris longus
. Flexor digitorum profundus and flexor pollicis longus
. Extensor digitorum communis and extensor carpi ulnaris
. Brachioradialis and supinator

Correct Answer & Explanation

. Flexor digitorum profundus and flexor pollicis longus

Explanation

The deep volar compartment of the forearm contains the flexor digitorum profundus (FDP), flexor pollicis longus (FPL), and pronator quadratus. Due to their deep location adjacent to the interosseous membrane, these muscles are most severely affected by elevated compartment pressures.

Question 5206

Topic: 2. Trauma
A 25-year-old male sustains a vertically oriented (Pauwels type III) femoral neck fracture. To maximize biomechanical stability and minimize shear forces across the fracture site, which fixation strategy is most appropriate?
. Three parallel cancellous screws placed in an inverted triangle
. Dynamic hip screw (sliding hip screw) with an anti-rotation screw
. Cephalomedullary nail with a single lag screw
. Two parallel cancellous screws
. Non-operative management with skeletal traction

Correct Answer & Explanation

. Dynamic hip screw (sliding hip screw) with an anti-rotation screw

Explanation

Pauwels type III fractures experience high vertical shear forces. A fixed-angle device, such as a sliding hip screw with an anti-rotation screw, provides superior biomechanical stability compared to parallel cancellous screws in vertically oriented fractures.

Question 5207

Topic: Pelvic & Acetabular Trauma
A 30-year-old male is brought to the trauma bay following a motorcycle crash. His pelvis is mechanically unstable (APC III pattern), his blood pressure is 70/40 mmHg, and his heart rate is 130 bpm. A pelvic binder is applied, and he remains hypotensive despite 2 liters of crystalloid and 2 units of PRBCs. FAST exam is negative. What is the most appropriate next step?
. Bilateral retrograde intramedullary femoral nailing
. Pelvic angiography with embolization or pre-peritoneal packing
. Immediate open reduction and internal fixation of the symphysis pubis
. Laparotomy for bowel exploration
. Application of an external fixator followed by CT scan

Correct Answer & Explanation

. Pelvic angiography with embolization or pre-peritoneal packing

Explanation

In a hemodynamically unstable patient with a pelvic ring injury and a negative FAST scan, the source of bleeding is retroperitoneal. Pre-peritoneal pelvic packing or angiography with embolization is the critical next step to achieve hemostasis.

Question 5208

Topic: 2. Trauma

A 45-year-old male sustains a bicondylar tibial plateau fracture. CT imaging reveals a large, displaced posteromedial shear fragment. Which surgical approach and fixation strategy is most appropriate for addressing this specific fragment?

. Standard anterolateral approach with a single lateral locking plate
. Anteromedial approach with an anterior-to-posterior lag screw
. Posteromedial approach with an anti-glide plate placed at the apex of the fragment
. Direct posterior approach using a gastrocnemius flap
. External fixation bridging the knee without internal fixation

Correct Answer & Explanation

. Posteromedial approach with an anti-glide plate placed at the apex of the fragment

Explanation

A displaced posteromedial shear fragment in a tibial plateau fracture cannot be adequately reduced and stabilized from an anterolateral approach. A posteromedial approach with an anti-glide or buttress plate provides biomechanically superior fixation against vertical shear forces.

Question 5209

Topic: 2. Trauma

A 28-year-old male with a closed tibial shaft fracture complains of severe leg pain out of proportion to the injury. His diastolic blood pressure is 80 mmHg. Intracompartmental pressure monitoring is performed. At what threshold is fasciotomy definitively indicated based on the delta pressure concept?

. Absolute pressure greater than 30 mmHg regardless of blood pressure
. Delta pressure (Diastolic BP - Compartment Pressure) less than 30 mmHg
. Delta pressure (Systolic BP - Compartment Pressure) less than 40 mmHg
. Delta pressure (Mean Arterial Pressure - Compartment Pressure) less than 20 mmHg
. Absolute pressure greater than 45 mmHg with a normal physical exam

Correct Answer & Explanation

. Delta pressure (Diastolic BP - Compartment Pressure) less than 30 mmHg

Explanation

The delta pressure is calculated as Diastolic Blood Pressure minus Compartment Pressure. A delta pressure of less than 30 mmHg is the most reliable threshold indicating inadequate tissue perfusion and the need for emergent fasciotomy.

Question 5210

Topic: 2. Trauma
A 30-year-old sustained a Hawkins Type III talar neck fracture 8 weeks ago, treated with ORIF. A subchondral radiolucent band is seen on the dome of the talus on an AP ankle radiograph. What does this radiographic finding indicate?
. Avascular necrosis of the talar body
. Imminent collapse of the talar dome
. Revascularization and intact blood supply
. Infection of the tibiotalar joint
. Nonunion of the talar neck

Correct Answer & Explanation

. Revascularization and intact blood supply

Explanation

The subchondral radiolucent band is known as Hawkins sign. It represents subchondral atrophy secondary to hyperemia, indicating that the talar body has an intact vascular supply and avascular necrosis is unlikely.

Question 5211

Topic: 2. Trauma

A 25-year-old motorcyclist sustains a severely comminuted open tibial shaft fracture with a 12-cm soft-tissue defect and exposed bone after extensive debridement. Pulses are symmetric to the contralateral limb. According to the Godina principles, to optimize outcomes, soft-tissue coverage with a free flap should ideally be performed within what timeframe?

. 24 hours
. 72 hours
. 7 days
. 14 days
. 21 days

Correct Answer & Explanation

. 72 hours

Explanation

Godina originally described that early free flap coverage within 72 hours for severe open tibial fractures significantly reduces flap failure and infection rates. Modern literature supports coverage as early as safely possible, making 72 hours the best classical and board-tested answer.

Question 5212

Topic: 2. Trauma

A 35-year-old multitrauma patient with bilateral femur fractures arrives at the trauma bay. Which of the following physiologic parameters is the strongest indication to proceed with damage control orthopedics (external fixation) rather than early total care (intramedullary nailing)?

. Serum lactate of 1.5 mmol/L
. Base deficit of -8 mEq/L
. Urine output of 45 mL/hr
. Systolic blood pressure of 110 mm Hg
. Heart rate of 95 beats per minute

Correct Answer & Explanation

. Base deficit of -8 mEq/L

Explanation

A base deficit worse than -6 mEq/L or a lactate > 2.5 mmol/L indicates inadequate tissue perfusion and physiologic exhaustion, making the patient 'borderline' or 'unstable'. In such scenarios, damage control orthopedics is preferred to avoid the 'second hit' of intramedullary nailing.

Question 5213

Topic: 2. Trauma

According to the Lower Extremity Assessment Project (LEAP) study, which of the following statements regarding severe lower extremity trauma is most accurate?

. A MESS score greater than 7 is an absolute indication for amputation.
. Initial absence of plantar sensation dictates primary amputation.
. Outcomes at 2 years are similar between successful salvage and amputation.
. Primary amputation results in significantly lower long-term psychological distress.
. Revascularization guarantees successful limb salvage.

Correct Answer & Explanation

. Outcomes at 2 years are similar between successful salvage and amputation.

Explanation

The LEAP study demonstrated that functional outcomes at two years are similar between patients who undergo limb salvage and those who undergo amputation. Initial absence of plantar sensation was found not to be a reliable predictor of long-term functional outcome.

Question 5214

Topic: 2. Trauma

Six weeks following open reduction and internal fixation of a Hawkins Type II talar neck fracture, an anteroposterior radiograph of the ankle reveals subchondral radiolucency in the talar dome. This radiographic finding indicates which of the following?

. Onset of post-traumatic arthritis
. Nonunion of the talar neck
. Avascular necrosis of the talar body
. Intact vascularity to the talar body
. Infection of the talocrural joint

Correct Answer & Explanation

. Intact vascularity to the talar body

Explanation

The presence of subchondral radiolucency in the talar dome at 6 to 8 weeks post-injury is known as the Hawkins sign. It represents subchondral osteopenia secondary to hyperemia, indicating intact vascularity and a low risk of avascular necrosis.

Question 5215

Topic: 2. Trauma

During an olecranon osteotomy approach for open reduction and internal fixation of an intra-articular distal humerus fracture, what is the optimal shape of the osteotomy to maximize stability upon repair?

. Transverse osteotomy
. Oblique osteotomy from proximal-dorsal to distal-volar
. Chevron (V-shaped) osteotomy with the apex pointing distally
. Chevron osteotomy with the apex pointing proximally
. Step-cut osteotomy

Correct Answer & Explanation

. Chevron (V-shaped) osteotomy with the apex pointing distally

Explanation

A chevron (V-shaped) osteotomy with the apex pointing distally is preferred because it provides excellent inherent rotational and translational stability when repaired. This shape maximizes the bony contact area to promote healing.

Question 5216

Topic: Pelvic & Acetabular Trauma
A 42-year-old male arrives in the trauma bay with an APC-III pelvic ring injury and a systolic blood pressure of 75 mmHg. A pelvic binder is applied. What is the correct anatomical placement for the pelvic binder to effectively reduce pelvic volume?
. Over the iliac crests
. At the level of the greater trochanters
. Over the umbilicus
. Just proximal to the anterior superior iliac spines (ASIS)
. Around the mid-thighs

Correct Answer & Explanation

. At the level of the greater trochanters

Explanation

To effectively reduce pelvic volume and stabilize the pelvic ring in an anteroposterior compression (APC) injury, a pelvic binder or sheet must be centered at the level of the greater trochanters. Placing it over the iliac crests is ineffective and can exacerbate the deformity.

Question 5217

Topic: 2. Trauma

A 22-year-old collegiate basketball player sustains a fracture at the metaphyseal-diaphyseal junction of the fifth metatarsal. He is treated with intramedullary screw fixation. This specific fracture location is prone to nonunion primarily due to which of the following vascular anatomical features?

. Robust periosteal blood supply inhibiting endosteal healing
. A vascular watershed area between the metaphyseal and diaphyseal blood supply
. Retrograde blood flow from the nutrient artery
. Disruption of the dominant dorsal pedal artery branch
. Lack of intraosseous anastomoses in the tuberosity

Correct Answer & Explanation

. A vascular watershed area between the metaphyseal and diaphyseal blood supply

Explanation

A true Jones fracture occurs at the metaphyseal-diaphyseal junction of the fifth metatarsal. This region is a vascular "watershed" area with limited blood supply, leading to a higher risk of delayed union or nonunion.

Question 5218

Topic: 2. Trauma

A 25-year-old male presents with a closed tibial shaft fracture and complains of pain out of proportion to his injury. His blood pressure is 110/70 mm Hg. Compartment pressure measurements reveal an anterior compartment pressure of 35 mm Hg. Which of the following criteria best indicates the need for emergent fasciotomy?

. Absolute compartment pressure greater than 30 mm Hg
. Diastolic blood pressure minus compartment pressure less than 30 mm Hg
. Systolic blood pressure minus compartment pressure less than 40 mm Hg
. Mean arterial pressure minus compartment pressure less than 50 mm Hg
. Absolute compartment pressure greater than 40 mm Hg

Correct Answer & Explanation

. Diastolic blood pressure minus compartment pressure less than 30 mm Hg

Explanation

The threshold for emergent fasciotomy in compartment syndrome is typically a delta pressure (diastolic blood pressure minus intracompartmental pressure) of less than 30 mm Hg. This is more reliable than absolute pressure measurements alone.

Question 5219

Topic: 2. Trauma
A 6-year-old boy falls from monkey bars and sustains a proximal third ulnar shaft fracture with an associated anterior dislocation of the radial head. According to the Bado classification, what type of Monteggia lesion is this?
. Type I
. Type II
. Type III
. Type IV
. Type V

Correct Answer & Explanation

. Type I

Explanation

A Bado Type I Monteggia fracture-dislocation involves a fracture of the proximal or middle third of the ulna with an anterior dislocation of the radial head. It is the most common type in the pediatric population.

Question 5220

Topic: 2. Trauma

A 24-year-old male sustains a low-velocity gunshot wound to the thigh resulting in a comminuted midshaft femur fracture. The bullet passed cleanly through the soft tissues without hitting major neurovascular structures. What is the most appropriate management?

. Immediate aggressive surgical debridement of the entire bullet tract and external fixation
. Local wound care, tetanus prophylaxis, short-course antibiotics, and intramedullary nailing
. Intravenous antibiotics for 14 days and skeletal traction
. Immediate plate osteosynthesis with structural bone grafting
. Primary amputation

Correct Answer & Explanation

. Local wound care, tetanus prophylaxis, short-course antibiotics, and intramedullary nailing

Explanation

Low-velocity gunshot wounds resulting in femur fractures without major neurovascular compromise or massive soft tissue destruction can typically be managed safely with local wound care, tetanus prophylaxis, short-course antibiotics, and standard intramedullary nailing.

Test Yourself

Switch to an interactive, timed exam simulation to truly master this topic.

On this Page