Menu

2. Trauma MCQs

Practice Set 283 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 5641

Topic: 2. Trauma

A 30-year-old man falls from a height and sustains a talar neck fracture. Six weeks postoperatively, an AP radiograph of the ankle reveals a subchondral radiolucent band extending across the dome of the talus. What is the clinical significance of this radiographic finding?

. It is an early sign of avascular necrosis of the talar body.
. It indicates an ongoing nonunion at the fracture site.
. It suggests intact vascularity to the talar body.
. It represents a postoperative infection.
. It is pathognomonic for a post-traumatic osteochondral defect.

Correct Answer & Explanation

. It suggests intact vascularity to the talar body.

Explanation

The finding described is Hawkins sign, which is a subchondral radiolucent band seen in the talar dome 6 to 8 weeks after a talar neck fracture. It represents subchondral osteopenia secondary to hyperemia from disuse. Its presence is a positive prognostic indicator, confirming that the talar body has an intact blood supply and is unlikely to develop avascular necrosis.

Question 5642

Topic: Pelvic & Acetabular Trauma
A 42-year-old male is brought to the trauma bay after a crush injury. Pelvic radiographs show widening of the pubic symphysis of 3.5 cm and disruption of the anterior sacroiliac ligaments, but intact posterior sacroiliac ligaments. According to the Young-Burgess classification, which type of pelvic ring injury does this represent?
. APC I
. APC II
. APC III
. LC I
. LC II

Correct Answer & Explanation

. APC II

Explanation

The Young-Burgess classification divides anteroposterior compression (APC) injuries into three types. APC I: symphysis widening <2.5 cm with intact SI ligaments. APC II: symphysis widening >2.5 cm with disruption of the anterior SI, sacrotuberous, and sacrospinous ligaments, but INTACT posterior SI ligaments (rotationally unstable, vertically stable). APC III involves complete disruption of anterior and posterior SI ligaments.

Question 5643

Topic: 2. Trauma



A 40-year-old male sustains a distal femur fracture. CT imaging reveals a coronal plane fracture of the lateral femoral condyle. This specific fracture pattern (Hoffa fracture) is best stabilized with which of the following internal fixation constructs to resist the primary deforming forces?

. Lateral locking plate only
. Medial and lateral tension band wiring
. Anterior-to-posterior (AP) or posterior-to-anterior (PA) interfragmentary lag screws
. Antegrade intramedullary nail
. External fixation

Correct Answer & Explanation

. Anterior-to-posterior (AP) or posterior-to-anterior (PA) interfragmentary lag screws

Explanation

A Hoffa fracture is a coronal plane fracture of the femoral condyle (most commonly lateral). Due to its vertical orientation, lateral plating alone often fails to adequately compress the fracture. The gold standard for stabilizing a Hoffa fragment is interfragmentary lag screw fixation directed anterior-to-posterior (AP) or posterior-to-anterior (PA), providing compression perpendicular to the fracture line.

Question 5644

Topic: Pelvic & Acetabular Trauma
A 35-year-old male is brought to the trauma bay following a high-speed motorcycle collision. A pelvic binder was placed in the field. Anteroposterior (AP) pelvis radiograph reveals an anterior-posterior compression (APC) injury. His pubic symphysis is widened by 3.5 cm, but the posterior pelvic ring appears grossly intact on initial imaging. In an APC-II pelvic ring injury, which of the following ligamentous structures remains intact?
. Anterior sacroiliac ligament
. Sacrospinous ligament
. Sacrotuberous ligament
. Posterior sacroiliac ligament
. Pubic symphyseal ligaments

Correct Answer & Explanation

. Posterior sacroiliac ligament

Explanation

According to the Young-Burgess classification, an APC-II injury is characterized by rupture of the pubic symphysis, anterior sacroiliac ligaments, sacrospinous ligaments, and sacrotuberous ligaments, resulting in an 'open book' pelvis. The posterior sacroiliac ligaments remain intact, providing vertical stability but allowing rotational instability. Rupture of the posterior sacroiliac ligaments would result in an APC-III injury, which is completely unstable both rotationally and vertically.

Question 5645

Topic: 2. Trauma

A 45-year-old female presents to the emergency department after falling on an outstretched hand. Radiographs show a fracture of the distal radius involving the volar rim, with the carpus subluxated volarly along with the fracture fragment. Which eponymous term correctly describes this injury pattern?

. Colles fracture
. Smith fracture
. Barton fracture
. Chauffeur fracture
. Die-punch fracture

Correct Answer & Explanation

. Barton fracture

Explanation

A Barton fracture is a shear fracture of the distal radius articular surface (can be volar or dorsal, though volar is more common) accompanied by subluxation or dislocation of the carpus along with the fractured articular fragment. A Colles fracture is a distally radiused fracture with dorsal displacement. A Smith fracture is a distal radius fracture with volar displacement. A Chauffeur fracture involves the radial styloid. A Die-punch fracture involves the lunate facet.

Question 5646

Topic: 2. Trauma
A 28-year-old male is admitted after suffering a closed, highly comminuted tibia fracture from a motor vehicle accident. Twelve hours post-admission, he develops severe, unrelenting leg pain out of proportion to the injury. His systemic blood pressure is 115/70 mmHg. Intracompartmental pressure monitoring of the anterior compartment yields a pressure of 45 mmHg. What is the patient's delta P (ΔP), and what is the most appropriate next step in management?
. ΔP = 70 mmHg; continue observation
. ΔP = 45 mmHg; administer intravenous pain medication
. ΔP = 25 mmHg; emergent four-compartment fasciotomy
. ΔP = 25 mmHg; bivalve the cast and elevate the leg above the heart
. ΔP = 30 mmHg; emergent four-compartment fasciotomy

Correct Answer & Explanation

. ΔP = 25 mmHg; emergent four-compartment fasciotomy

Explanation

Acute compartment syndrome is a surgical emergency. The delta P (ΔP) is calculated as the Diastolic Blood Pressure minus the Compartment Pressure. Here, ΔP = 70 mmHg - 45 mmHg = 25 mmHg. A ΔP of less than 30 mmHg is an absolute indication for emergent fasciotomy to release the fascial compartments and restore tissue perfusion. Elevating the leg above the heart actually decreases local arterial perfusion pressure and is contraindicated in suspected compartment syndrome.

Question 5647

Topic: 2. Trauma

A 35-year-old male sustains a distal femur fracture. CT scan reveals a coronal plane fracture of the lateral femoral condyle.

Which surgical approach is most appropriate for direct visualization and reduction of this specific intra-articular fragment?

. Medial parapatellar approach
. Direct lateral approach to the distal femur
. Lateral parapatellar approach
. Swashbuckler (extended lateral) approach
. Subvastus approach

Correct Answer & Explanation

. Swashbuckler (extended lateral) approach

Explanation

A coronal plane fracture of the femoral condyle is a Hoffa fracture (AO 33-B3). The lateral condyle is most commonly affected. The Swashbuckler (extended lateral) approach provides excellent exposure of the distal femur, including the lateral articular surface, for open reduction and internal fixation of distal femur fractures with intra-articular coronal plane components.

Question 5648

Topic: Pelvic & Acetabular Trauma
A 45-year-old male is brought to the ED after a motorcycle crash. His pelvis is unstable. Radiographs show symphyseal diastasis of 3.5 cm and widening of the anterior sacroiliac joints, but the posterior SI ligaments remain intact. According to the Young-Burgess classification, what type of injury is this?
. APC I
. APC II
. APC III
. LC I
. LC II

Correct Answer & Explanation

. APC II

Explanation

Anterior-Posterior Compression (APC) injuries: APC I is symphysis widening < 2.5 cm with intact posterior ligaments. APC II is symphysis widening > 2.5 cm, torn anterior SI, sacrotuberous, and sacrospinous ligaments, but INTACT posterior SI ligaments (rotationally unstable, vertically stable). APC III involves disruption of both anterior and posterior SI ligaments (rotationally and vertically unstable).

Question 5649

Topic: Lower Extremity Trauma
A 40-year-old pedestrian is struck by a motor vehicle, sustaining a severe valgus force to the knee. Computed tomography reveals a pure central depression fracture of the lateral tibial plateau, with the lateral cortical rim remaining intact. According to the Schatzker classification system, how is this fracture pattern classified?
. Schatzker I
. Schatzker II
. Schatzker III
. Schatzker IV
. Schatzker V

Correct Answer & Explanation

. Schatzker III

Explanation

Schatzker III fractures are pure central depressions of the lateral tibial plateau without an associated split of the lateral margin. Schatzker I is a pure wedge split of the lateral plateau. Schatzker II is a split-depression of the lateral plateau (most common). Schatzker IV involves the medial plateau. Schatzker V is a bicondylar fracture with intact metaphyseal-diaphyseal continuity. Schatzker VI involves metaphyseal-diaphyseal dissociation.

Question 5650

Topic: 2. Trauma
A 38-year-old skier falls and twists her knee. Radiographs and CT show a fracture of the lateral tibial plateau characterized by a split wedge fragment with central articular depression. According to the Schatzker classification, what type of fracture is this?
. Type I
. Type II
. Type III
. Type IV
. Type V

Correct Answer & Explanation

. Type II

Explanation

Schatzker classification of tibial plateau fractures: Type I = lateral split wedge. Type II = lateral split with central depression (the most common type overall). Type III = pure lateral depression. Type IV = medial plateau fracture. Type V = bicondylar fracture. Type VI = plateau fracture with metadiaphyseal dissociation.

Question 5651

Topic: Lower Extremity Trauma

A 45-year-old male feels a 'pop' in his posterior knee while squatting. MRI reveals a radial tear at the attachment site of the posterior horn of the medial meniscus.

Biomechanical studies indicate that a complete posterior root tear of the medial meniscus leads to which of the following?

. Decreased peak contact pressures in the medial compartment.
. A kinematic equivalent of a completely intact meniscus due to the intact meniscofemoral ligaments.
. Biomechanical equivalent of a total medial meniscectomy.
. Increased anterior translation of the tibia in extension.
. Subluxation of the lateral meniscus.

Correct Answer & Explanation

. Biomechanical equivalent of a total medial meniscectomy.

Explanation

The posterior root firmly anchors the medial meniscus to the tibial plateau, allowing it to convert axial loads into circumferential hoop stresses. A complete root tear severely disrupts these hoop stresses, leading to functional meniscal extrusion. Biomechanically, this failure is equivalent to a total medial meniscectomy, causing drastically increased peak contact pressures.

Question 5652

Topic: 2. Trauma

Which of the following surgical approaches is most appropriate for a posteromedial tibial plateau fracture?

. Anterolateral approach
. Medial approach
. Posteromedial approach
. Posterolateral approach
. Anterior mid-line approach

Correct Answer & Explanation

. Posteromedial approach

Explanation

Posteromedial shear fractures of the tibial plateau require buttress plating on the posteromedial surface. A posteromedial approach interval is between the medial head of the gastrocnemius and the pes anserinus.

Question 5653

Topic: 2. Trauma
A 35-year-old male sustains a vertically oriented (Pauwels type III) basicervical femoral neck fracture. Which of the following fixation constructs offers the highest biomechanical stability for this specific fracture pattern?
. Three parallel cancellous screws
. Sliding hip screw (SHS) alone
. Sliding hip screw with an anti-rotation screw
. Cephalomedullary nail
. Dynamic condylar screw

Correct Answer & Explanation

. Sliding hip screw with an anti-rotation screw

Explanation

Vertical fracture patterns (Pauwels III) experience high shear forces. A sliding hip screw (SHS) provides better resistance to vertical shear compared to cancellous screws. The addition of an anti-rotation (derotational) screw superior to the SHS provides optimal stability.

Question 5654

Topic: Pelvic & Acetabular Trauma
In an anteroposterior compression (APC) type III pelvic ring injury, the symphysis pubis is widely disrupted, and the hemipelvis is completely unstable. Which of the following posterior ligamentous structures is completely disrupted in an APC III injury but intact in an APC II injury?
. Anterior sacroiliac ligaments
. Sacrospinous ligaments
. Sacrotuberous ligaments
. Posterior sacroiliac ligaments
. Iliolumbar ligaments

Correct Answer & Explanation

. Posterior sacroiliac ligaments

Explanation

APC II injuries involve disruption of the symphysis pubis, anterior sacroiliac ligaments, and the sacrospinous and sacrotuberous ligaments, but the posterior sacroiliac ligaments remain intact (opening book). In APC III, there is complete disruption of the anterior and posterior sacroiliac ligaments, leading to a completely unstable hemipelvis.

Question 5655

Topic: 2. Trauma

A 28-year-old male sustained a displaced talar neck fracture and underwent open reduction and internal fixation.

Six weeks postoperatively, a subchondral radiolucent band is seen in the talar dome on the AP mortise radiograph. What does this radiographic finding indicate?

. Impending avascular necrosis of the talar body
. Nonunion of the fracture site
. Infection of the tibiotalar joint
. Intact vascularity to the talar body
. Early manifestation of post-traumatic subtalar arthritis

Correct Answer & Explanation

. Intact vascularity to the talar body

Explanation

Hawkins sign is a subchondral radiolucent band seen in the talar dome 6 to 8 weeks after a talus fracture. It represents subchondral osteopenia secondary to disuse atrophy. Because bone resorption requires an active blood supply, the presence of a Hawkins sign is a highly reliable indicator that the talar body has intact vascularity and that avascular necrosis (AVN) is unlikely.

Question 5656

Topic: Lower Extremity Trauma

A 45-year-old patient sustains a bicondylar tibial plateau fracture (Schatzker VI) with a displaced posteromedial fragment.

When utilizing a posteromedial approach to buttress this fragment, the surgical dissection typically exploits the internervous/intermuscular interval between which two structures?

. Tibialis anterior and extensor hallucis longus
. Popliteus and soleus
. Lateral head of the gastrocnemius and biceps femoris
. Medial head of the gastrocnemius and the pes anserinus
. Flexor digitorum longus and tibialis posterior

Correct Answer & Explanation

. Medial head of the gastrocnemius and the pes anserinus

Explanation

The posteromedial approach to the tibial plateau utilizes the interval between the medial head of the gastrocnemius (which is retracted posteriorly along with the neurovascular bundle) and the pes anserinus (which is retracted anteriorly). This provides direct access to the posteromedial metaphysis to place an anti-glide buttress plate.

Question 5657

Topic: Pelvic & Acetabular Trauma
A 35-year-old male sustains an APC-III pelvic ring injury following a high-speed motorcycle collision. After initial hemodynamic stabilization, the surgeon elects to perform an open reduction and internal fixation of a widened sacroiliac (SI) joint via an anterior approach. During dissection and plate placement over the sacral ala, which neurological structure is at greatest risk of iatrogenic injury?
. L3 nerve root
. L4 nerve root
. L5 nerve root
. S1 nerve root
. Sciatic nerve

Correct Answer & Explanation

. L5 nerve root

Explanation

During the anterior approach to the sacroiliac joint, the L5 nerve root is at significant risk. It courses directly over the sacral ala, typically approximately 2 cm medial to the SI joint, before joining the sacral plexus. Retraction or misplaced drills/screws in this region can easily injure the L5 root, leading to foot drop and sensory deficits.

Question 5658

Topic: 2. Trauma

A 68-year-old female undergoes open reduction and internal fixation of a 3-part proximal humerus fracture using a locking plate. Three months postoperatively, radiographs demonstrate a varus collapse of the humeral head and subsequent 'cut-out' of the proximal locking screws into the glenohumeral joint. Which of the following technical errors during the index procedure is the most significant risk factor for this complication?

. Failure to repair the subscapularis tendon
. Use of a deltopectoral rather than a deltoid-splitting approach
. Failure to place the plate exactly 2 cm distal to the greater tuberosity
. Lack of medial calcar support restoration
. Placement of more than four proximal locking screws

Correct Answer & Explanation

. Lack of medial calcar support restoration

Explanation

The most critical biomechanical factor in preventing varus collapse and secondary screw cut-out in proximal humerus fracture plating is the restoration of medial calcar support. This is achieved by anatomically reducing the medial cortex and, critically, by placing the inferior-most locking screws (calcar screws) accurately into the inferomedial quadrant of the humeral head. If severe comminution exists, structural allograft strut augmentation may be required.

Question 5659

Topic: Pelvic & Acetabular Trauma
A 35-year-old male is involved in a high-speed motor vehicle collision and sustains the pelvic ring injury shown below. In an Anteroposterior Compression Type III (APC-III) injury, which ligamentous complex is completely disrupted resulting in global pelvic instability?
. Anterior sacroiliac ligaments only
. Anterior sacroiliac and sacrospinous ligaments only
. Anterior sacroiliac, sacrospinous, sacrotuberous, and posterior sacroiliac ligaments
. Sacrotuberous ligaments only
. Iliolumbar ligaments only

Correct Answer & Explanation

. Anterior sacroiliac, sacrospinous, sacrotuberous, and posterior sacroiliac ligaments

Explanation

An APC-III injury represents a complete disruption of both the anterior and posterior pelvic rings. The symphysis is widened, and there is complete disruption of the anterior sacroiliac (SI), sacrospinous, sacrotuberous, and posterior SI ligaments. This results in global instability (both rotational and vertical). APC-II injuries typically spare the posterior SI ligaments.

Question 5660

Topic: 2. Trauma

A 28-year-old male sustains a high-energy basicervical femoral neck fracture. He undergoes closed reduction and percutaneous pinning with three cannulated screws. Which of the following screw configurations provides the most biomechanically stable construct?

. Inverted triangle configuration with screws placed adjacent to the anterior, posterior, and inferior cortices
. Triangle configuration with apex superior, centrally located in the femoral neck
. Two parallel screws placed centrally
. Three divergent screws originating from the lateral cortex
. Four parallel screws clustered centrally

Correct Answer & Explanation

. Inverted triangle configuration with screws placed adjacent to the anterior, posterior, and inferior cortices

Explanation

For cannulated screw fixation of femoral neck fractures, the most biomechanically stable construct is an inverted triangle configuration. The screws should be placed as far apart as possible, immediately adjacent to the inferior calcar, anterior, and posterior cortices to maximize the spread and leverage, increasing resistance to bending and torsional forces.

Test Yourself

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

On this Page