Menu

2. Trauma MCQs

Practice Set 301 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 6001

Topic: 2. Trauma

A patient sustains a complex bicondylar tibial plateau fracture with a large posteromedial fragment. To adequately reduce and buttress this specific fragment, which surgical approach is most appropriate?

. Standard anterolateral approach with submeniscal arthrotomy
. Medial approach with elevation of the pes anserinus
. Posteromedial approach utilizing the interval between the medial head of the gastrocnemius and the pes anserinus
. Direct posterior approach through the popliteal fossa
. Anteromedial approach through the medial patellar retinaculum

Correct Answer & Explanation

. Posteromedial approach utilizing the interval between the medial head of the gastrocnemius and the pes anserinus

Explanation

A posteromedial shear fragment in a tibial plateau fracture (frequently seen in Schatzker IV or VI patterns) cannot be adequately reduced or plated through a standard anteromedial or anterolateral approach. A posteromedial approach is required, which utilizes the internervous/intermuscular interval between the medial head of the gastrocnemius (posteriorly) and the pes anserinus (anteriorly). This allows direct visualization of the posteromedial cortex for optimal anti-glide plating.

Question 6002

Topic: 2. Trauma
In a patient presenting with hemorrhagic shock secondary to a severe anterior-posterior compression (APC-III) pelvic ring injury, what is the most common anatomical source of the massive retroperitoneal hemorrhage?
. Superior gluteal artery
. Internal pudendal artery
. Obturator artery
. Presacral venous plexus
. External iliac vein

Correct Answer & Explanation

. Presacral venous plexus

Explanation

While arterial bleeding (such as from the superior gluteal or internal pudendal arteries) can occur and is life-threatening, up to 80-90% of pelvic hemorrhage in the setting of blunt trauma originates from the venous presacral and prevesical plexuses, as well as bleeding from the fractured cancellous bone surfaces.

Question 6003

Topic: 2. Trauma

A 32-year-old man sustains a closed highly-comminuted tibial shaft fracture. He complains of severe pain out of proportion to the injury that worsens with passive stretch. His blood pressure is 120/80 mmHg. Intracompartmental pressure monitoring is performed. According to the 'Delta P' theory, what is the critical threshold indicating the need for emergent four-compartment fasciotomy?

. Absolute compartment pressure > 30 mmHg
. Absolute compartment pressure > 45 mmHg
. Diastolic blood pressure minus compartment pressure < 30 mmHg
. Mean arterial pressure minus compartment pressure < 40 mmHg
. Systolic blood pressure minus compartment pressure < 30 mmHg

Correct Answer & Explanation

. Diastolic blood pressure minus compartment pressure < 30 mmHg

Explanation

The 'Delta P' concept for diagnosing acute compartment syndrome states that the difference between the diastolic blood pressure and the absolute compartment pressure (Delta P = Diastolic BP - Compartment Pressure) is a more accurate predictor of muscle ischemia than absolute compartment pressure alone. A Delta P of less than 30 mmHg is the widely accepted threshold that dictates the need for emergent fasciotomy, as capillary perfusion is severely compromised below this pressure gradient.

Question 6004

Topic: 2. Trauma

A 22-year-old female soccer player sustains a twisting injury to her knee. Radiographs reveal an avulsion fracture of the lateral tibial plateau (Segond fracture). This radiographic finding is pathognomonic for a major injury to which of the following structures?

. Posterior cruciate ligament
. Medial collateral ligament
. Anterior cruciate ligament
. Lateral meniscus
. Iliotibial band

Correct Answer & Explanation

. Anterior cruciate ligament

Explanation

A Segond fracture is an avulsion of the anterolateral ligament (ALL) or lateral capsular ligament from the lateral tibial plateau. It results from excessive internal rotation and varus stress, and is highly associated (often considered pathognomonic) with an anterior cruciate ligament (ACL) tear.

Question 6005

Topic: 2. Trauma
A 32-year-old male sustains a closed tibia fracture and presents with severe pain out of proportion to the injury. Which of the following pressure criteria is widely considered the threshold to indicate a fasciotomy for acute compartment syndrome?
. Absolute compartment pressure of 15 mm Hg
. Absolute compartment pressure of 20 mm Hg
. Delta pressure (Diastolic blood pressure minus compartment pressure) of less than 30 mm Hg
. Delta pressure (Mean arterial pressure minus compartment pressure) of less than 10 mm Hg
. Systolic blood pressure minus compartment pressure of less than 40 mm Hg

Correct Answer & Explanation

. Delta pressure (Diastolic blood pressure minus compartment pressure) of less than 30 mm Hg

Explanation

The currently accepted threshold for diagnosing and treating acute compartment syndrome is a delta pressure (diastolic blood pressure minus intracompartmental pressure) of ≤ 30 mm Hg. Using absolute compartment pressures is less reliable because capillary perfusion depends on the gradient between systemic diastolic pressure and local tissue pressure.

Question 6006

Topic: Pelvic & Acetabular Trauma
A 45-year-old male sustains an anteroposterior compression (APC) type II pelvic ring injury. Based on the Young-Burgess classification, an APC II injury is characterized by disruption of the symphysis pubis and which of the following posterior structures?
. Anterior sacroiliac, sacrotuberous, and sacrospinous ligaments
. Posterior sacroiliac ligaments only
. Both anterior and posterior sacroiliac ligaments
. Iliolumbar ligaments only
. Complete disruption of the pelvic floor and all sacroiliac ligaments

Correct Answer & Explanation

. Anterior sacroiliac, sacrotuberous, and sacrospinous ligaments

Explanation

In an APC II injury, the 'open book' mechanism causes widening of the symphysis pubis (>2.5 cm) and tearing of the anterior sacroiliac ligaments, as well as the sacrotuberous and sacrospinous ligaments. The strong posterior sacroiliac ligaments remain intact, leaving the pelvis rotationally unstable but vertically stable. Complete disruption involving the posterior SI ligaments defines an APC III injury.

Question 6007

Topic: 2. Trauma

An intra-articular fracture of the distal radius characterized by a volar shear fracture of the lunate facet, typically resulting in volar subluxation of the carpus along with the fracture fragment, is known by which eponym?

. Colles fracture
. Smith fracture
. Volar Barton fracture
. Chauffeur's fracture
. Die-punch fracture

Correct Answer & Explanation

. Volar Barton fracture

Explanation

A volar Barton fracture is an intra-articular shear fracture of the volar rim of the distal radius, classically accompanied by volar subluxation or dislocation of the radiocarpal joint. A Colles fracture is extra-articular with dorsal angulation. A Smith fracture is extra-articular with volar angulation. A Chauffeur's fracture is an intra-articular fracture of the radial styloid.

Question 6008

Topic: Pelvic & Acetabular Trauma

In an anteroposterior compression (APC) type II pelvic ring injury (Young-Burgess classification), which of the following ligaments are typically ruptured?

. Anterior sacroiliac, sacrotuberous, and sacrospinous ligaments
. Posterior sacroiliac and iliolumbar ligaments
. Anterior sacroiliac and posterior sacroiliac ligaments
. Sacrotuberous, sacrospinous, and posterior sacroiliac ligaments
. Sacrospinous, anterior sacroiliac, and iliolumbar ligaments

Correct Answer & Explanation

. Anterior sacroiliac, sacrotuberous, and sacrospinous ligaments

Explanation

APC II injuries involve a 'subluxed' sacroiliac joint characterized by rupture of the anterior sacroiliac ligament, as well as the sacrotuberous and sacrospinous ligaments. The posterior sacroiliac ligament complex remains intact, which maintains vertical stability despite rotational instability (open book pelvis).

Question 6009

Topic: 2. Trauma

Biomechanical studies evaluating the fixation of coronal shear fractures of the lateral femoral condyle (Hoffa fractures) have demonstrated that the most stable construct is achieved with which of the following techniques?

. Anterior-to-posterior oriented cancellous lag screws
. Posterior-to-anterior oriented cancellous lag screws
. Anterior-to-posterior oriented cortical screws without a plate
. Medial-to-lateral oriented fully threaded screws
. Tension band wiring technique

Correct Answer & Explanation

. Posterior-to-anterior oriented cancellous lag screws

Explanation

Biomechanical studies have shown that posterior-to-anterior (PA) directed lag screws provide superior biomechanical stability for Hoffa fractures compared to anterior-to-posterior (AP) directed screws. The PA trajectory places the screws more perpendicular to the coronal fracture plane, providing superior compression against the typical shear forces of joint loading.

Question 6010

Topic: 2. Trauma

A 25-year-old male is admitted with a highly comminuted midshaft tibia fracture. The clinical concern for acute compartment syndrome is high. Which of the following intracompartmental pressure measurements is considered the most reliable threshold for diagnosing acute compartment syndrome?

. Absolute intracompartmental pressure > 30 mmHg
. Absolute intracompartmental pressure > 45 mmHg
. Diastolic blood pressure minus intracompartmental pressure < 30 mmHg
. Mean arterial pressure minus intracompartmental pressure < 45 mmHg
. Systolic blood pressure minus intracompartmental pressure < 30 mmHg

Correct Answer & Explanation

. Diastolic blood pressure minus intracompartmental pressure < 30 mmHg

Explanation

The differential pressure (delta P) between the patient's diastolic blood pressure and the measured intracompartmental pressure is the most reliable and validated parameter for diagnosing acute compartment syndrome. A delta P of less than 30 mmHg (meaning the compartment pressure is within 30 mmHg of the diastolic pressure) is an absolute indication for emergency fasciotomy.

Question 6011

Topic: 2. Trauma

A 45-year-old male sustains a high-energy subtrochanteric femur fracture. Due to the muscular attachments on the proximal fracture fragment, what is the expected clinical deformity of the proximal segment?

. Extension, adduction, and internal rotation
. Flexion, adduction, and external rotation
. Flexion, abduction, and external rotation
. Extension, abduction, and internal rotation
. Flexion, abduction, and internal rotation

Correct Answer & Explanation

. Flexion, abduction, and external rotation

Explanation

The proximal fragment in a subtrochanteric fracture is characteristically displaced into flexion (by the iliopsoas muscle attaching to the lesser trochanter), abduction (by the gluteus medius and minimus attaching to the greater trochanter), and external rotation (by the short external rotators attaching to the posteromedial greater trochanter).

Question 6012

Topic: 2. Trauma

A 30-year-old male sustains a Hawkins Type II talar neck fracture. At the 6-week follow-up radiograph, a subchondral radiolucent band is noted in the dome of the talus (Hawkins sign). What does this radiographic finding indicate?

. Impending collapse of the talar dome
. Intact vascular supply and viability of the talar body
. Established avascular necrosis (AVN) of the talar body
. Nonunion of the talar neck fracture
. Post-traumatic osteomyelitis of the talus

Correct Answer & Explanation

. Intact vascular supply and viability of the talar body

Explanation

Hawkins sign is a subchondral radiolucency in the talar dome typically seen 6 to 8 weeks after a talar neck fracture. It represents subchondral atrophy due to disuse osteopenia, which requires an intact blood supply to occur. Therefore, the presence of Hawkins sign is a highly reliable indicator of talar body viability and virtually excludes the development of complete avascular necrosis (AVN).

Question 6013

Topic: 2. Trauma
Based on the Lauge-Hansen classification for ankle fractures, what is the defining structural failure in Stage III of a Supination-External Rotation (SER) injury mechanism?
. Rupture of the anterior inferior tibiofibular ligament (AITFL)
. Spiral or short oblique fracture of the lateral malleolus
. Rupture of the posterior inferior tibiofibular ligament (PITFL) or fracture of the posterior malleolus
. Transverse fracture of the medial malleolus
. Rupture of the superficial deltoid ligament only

Correct Answer & Explanation

. Rupture of the posterior inferior tibiofibular ligament (PITFL) or fracture of the posterior malleolus

Explanation

The Supination-External Rotation (SER) mechanism has four stages. Stage I: Rupture of the AITFL. Stage II: Spiral/oblique fracture of the distal fibula. Stage III: Rupture of the PITFL or avulsion fracture of its tibial attachment (posterior malleolus). Stage IV: Transverse fracture of the medial malleolus or rupture of the deltoid ligament.

Question 6014

Topic: 2. Trauma

A 35-year-old skier sustains a Schatzker type II tibial plateau fracture (split-depression of the lateral plateau). Which of the following is the most commonly associated intra-articular soft-tissue injury in this fracture pattern?

. Medial collateral ligament (MCL) complete tear
. Lateral meniscus tear
. Anterior cruciate ligament (ACL) complete rupture
. Posterior cruciate ligament (PCL) tear
. Patellar tendon avulsion

Correct Answer & Explanation

. Lateral meniscus tear

Explanation

Schatzker type II fractures (split-depression of the lateral tibial plateau) are caused by valgus and axial loading forces. The lateral meniscus is frequently torn or incarcerated within the fracture fragments (particularly the depressed articular fragment) in up to 50% of cases and must be addressed during surgical fixation.

Question 6015

Topic: 2. Trauma
A 25-year-old male sustains an open tibia fracture. The wound is a 5 cm laceration with moderate soft tissue damage, but there is adequate periosteal coverage of the bone and no massive contamination. According to the Gustilo-Anderson classification, what type of fracture is this, and what is the standard recommended initial antibiotic prophylaxis?
. Type I; first-generation cephalosporin
. Type II; first-generation cephalosporin
. Type IIIA; first-generation cephalosporin and an aminoglycoside
. Type IIIB; first-generation cephalosporin and an aminoglycoside
. Type II; first-generation cephalosporin and high-dose penicillin

Correct Answer & Explanation

. Type II; first-generation cephalosporin

Explanation

A Gustilo-Anderson Type II open fracture is characterized by a wound between 1 and 10 cm in length, moderate soft tissue damage, and adequate bone coverage, without the high-energy periosteal stripping seen in Type III injuries. The standard of care for initial antibiotic prophylaxis in a Type II open fracture is a first-generation cephalosporin (e.g., Cefazolin).

Question 6016

Topic: 2. Trauma

A 32-year-old man sustains a closed tibial shaft fracture and presents to the ER complaining of severe pain out of proportion to the injury. His blood pressure is 120/80 mmHg. Intracompartmental pressure testing is performed to evaluate for acute compartment syndrome. Which measurement strongly indicates the need for an emergent four-compartment fasciotomy?

. An absolute compartment pressure of 20 mmHg
. An absolute compartment pressure of 25 mmHg
. A delta pressure (Mean Arterial Pressure - compartment pressure) of 45 mmHg
. A delta pressure (Diastolic BP - compartment pressure) of 20 mmHg
. A delta pressure (Diastolic BP - compartment pressure) of 40 mmHg

Correct Answer & Explanation

. A delta pressure (Diastolic BP - compartment pressure) of 20 mmHg

Explanation

Acute compartment syndrome is definitively diagnosed using the delta pressure, which is calculated as the Diastolic Blood Pressure minus the Absolute Compartment Pressure. A delta pressure of < 30 mmHg indicates critically impaired tissue perfusion and is an absolute indication for emergent fasciotomy. A delta P of 20 mmHg (e.g., Diastolic 80 - Compartment 60 = 20) falls well below this critical threshold.

Question 6017

Topic: Lower Extremity Trauma

A 40-year-old male sustains a high-energy Schatzker VI tibial plateau fracture. Which of the following findings makes the utilization of a dual-incision (anterolateral and posteromedial) approach mandatory rather than a single lateral approach?

. Severe lateral articular depression
. Comminution of the anterior tibial tuberosity
. A displaced posteromedial coronal split fragment
. Involvement of the fibular head
. An associated meniscal tear

Correct Answer & Explanation

. A displaced posteromedial coronal split fragment

Explanation

A displaced posteromedial fragment is a classic indication for a posteromedial approach because it cannot be adequately reduced or buttressed from an anterolateral approach. A posteromedial buttress plate is typically required to resist the deforming shear forces during weight-bearing.

Question 6018

Topic: Pelvic & Acetabular Trauma
In a Young-Burgess APC-III (Anteroposterior Compression type III) pelvic ring injury, which of the following best describes the posterior ligamentous disruption compared to an APC-II injury?
. Disruption of anterior sacroiliac ligaments only.
. Disruption of anterior and posterior sacroiliac, sacrotuberous, and sacrospinous ligaments.
. Disruption of the sacrotuberous ligaments only.
. Disruption of the sacrospinous ligaments only.
. Complete avulsion of the iliolumbar ligament with an intact posterior SI complex.

Correct Answer & Explanation

. Disruption of anterior and posterior sacroiliac, sacrotuberous, and sacrospinous ligaments.

Explanation

An APC-II injury is characterized by symphyseal diastasis and disruption of the anterior sacroiliac (SI), sacrotuberous, and sacrospinous ligaments, but the posterior SI ligaments remain intact, providing rotational instability but vertical stability. An APC-III injury involves further energy, resulting in complete disruption of both anterior and posterior SI ligaments, as well as the sacrotuberous and sacrospinous ligaments, leading to both rotational and vertical instability.

Question 6019

Topic: 2. Trauma

In a Holstein-Lewis fracture of the humerus, the radial nerve is at highest risk of injury as it becomes tethered and compressed. This tethering most commonly occurs as the nerve passes through which of the following anatomic structures?

. The spiral groove of the humerus.
. The lateral intermuscular septum.
. The arcade of Frohse.
. The medial intermuscular septum.
. The triangular interval.

Correct Answer & Explanation

. The lateral intermuscular septum.

Explanation

A Holstein-Lewis fracture is a spiral fracture of the distal third of the humeral shaft. The radial nerve is at high risk of entrapment or laceration because it is relatively fixed as it pierces the lateral intermuscular septum to pass from the posterior compartment to the anterior compartment of the arm.

Question 6020

Topic: 2. Trauma
A 45-year-old male sustains a Schatzker type IV tibial plateau fracture following a high-energy motor vehicle collision. Which of the following associated injuries is most classically associated with this specific fracture pattern compared to a low-energy Schatzker type II fracture?
. Popliteal artery injury.
. Common peroneal nerve palsy.
. Superficial medial collateral ligament rupture.
. Anterior cruciate ligament avulsion.
. Lateral meniscus tear.

Correct Answer & Explanation

. Popliteal artery injury.

Explanation

A Schatzker type IV fracture is a medial tibial plateau fracture. It is typically the result of high-energy varus forces. Due to the high-energy nature and the proximity of the popliteal artery tethered at the trifurcation by the soleus arch, Schatzker IV fractures carry a significantly higher risk of vascular injury (popliteal artery) compared to lateral plateau (Schatzker I-III) fractures.

Test Yourself

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

On this Page