Menu

2. Trauma MCQs

Practice Set 385 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 7681

Topic: 2. Trauma

A 32-year-old man undergoes reamed intramedullary nailing for a closed comminuted tibial shaft fracture. Four hours postoperatively, he complains of severe, unrelenting leg pain resistant to intravenous opioids. His blood pressure is 110/70 mm Hg. Examination reveals a tense anterior calf and severe pain with passive plantar flexion of the toes. Which of the following compartment pressure measurements definitively indicates the need for immediate four-compartment fasciotomy?

. Absolute compartment pressure of 25 mm Hg
. Absolute compartment pressure of 30 mm Hg
. Difference between mean arterial pressure and compartment pressure of < 40 mm Hg
. Difference between systolic blood pressure and compartment pressure of < 40 mm Hg
. Difference between diastolic blood pressure and compartment pressure of < 30 mm Hg

Correct Answer & Explanation

. Absolute compartment pressure of 25 mm Hg

Explanation

The diagnostic threshold for acute compartment syndrome is a Delta P (diastolic blood pressure minus compartment pressure) of less than 30 mm Hg. Absolute pressure measurements are less reliable, particularly in hypotensive patients.

Question 7682

Topic: 2. Trauma

A 45-year-old woman is evaluated for a complex intra-articular distal femur fracture following a fall from height. A CT scan of the knee demonstrates a displaced coronal plane shear fracture of the lateral femoral condyle (Hoffa fracture). Which of the following isolated fixation strategies is biomechanically optimal for securing this specific condylar fragment?

. Placement of lag screws directed from anterior to posterior
. Placement of lag screws directed from posterior to anterior
. Application of a lateral locking plate alone
. Application of an anterior anti-glide plate
. Placement of lateral to medial fully threaded screws

Correct Answer & Explanation

. Placement of lag screws directed from anterior to posterior

Explanation

A Hoffa fracture is a coronal shear fracture of the femoral condyle, typically requiring independent lag screw fixation. Biomechanical studies show that anterior-to-posterior (AP) directed lag screws offer superior fixation strength by engaging the denser bone of the posterior condyle compared to PA screws.

Question 7683

Topic: 2. Trauma

A 28-year-old man sustains a high-energy closed midshaft femur fracture. Routine trauma radiographs of the femur, knee, and pelvis are obtained in the trauma bay. Which of the following statements regarding the evaluation and management of a potential ipsilateral femoral neck fracture in this patient is most accurate?

. The femoral neck fracture is typically displaced and easily identified on initial plain radiographs.
. A dedicated CT scan of the femoral neck is recommended, as up to 30% of these fractures are missed on initial radiographs.
. The shaft fracture should be addressed first, followed by closed reduction and percutaneous pinning of the neck.
. Retrograde nailing of the shaft is contraindicated if an ipsilateral neck fracture is identified.
. The typical ipsilateral femoral neck fracture is a low-angle Pauwels type I fracture.

Correct Answer & Explanation

. The femoral neck fracture is typically displaced and easily identified on initial plain radiographs.

Explanation

Ipsilateral femoral neck fractures occur in 2-6% of femoral shaft fractures, are often non-displaced, and are initially missed in up to 30% of cases. A dedicated fine-cut CT scan through the femoral neck is standard protocol to identify these typically vertical (Pauwels III) fractures.

Question 7684

Topic: 2. Trauma

Which of the following factors is most strongly associated with a high rate of nonunion in conservatively managed Type II odontoid fractures?

. Age less than 40 years
. Anterior displacement of 2 mm
. Initial displacement greater than 5 mm
. Concomitant anterior arch of C1 fracture
. Transverse fracture orientation

Correct Answer & Explanation

. Age less than 40 years

Explanation

Risk factors for nonunion of Type II odontoid fractures include initial displacement greater than 5 mm, age over 50 years, posterior displacement, and angulation greater than 10 degrees.

Question 7685

Topic: 2. Trauma

A 72-year-old woman presents with acute, severe localized mid-back pain after lifting a bag of groceries. Radiographs show a T7 anterior wedge compression fracture. Her neurologic examination is normal. What is the most appropriate initial management?

. Kyphoplasty
. Vertebroplasty
. Posterior spinal fusion
. Short course of bed rest followed by bracing and mobilization
. Anterior corpectomy

Correct Answer & Explanation

. Kyphoplasty

Explanation

Uncomplicated osteoporotic compression fractures in neurologically intact patients are primarily managed nonoperatively. A brief period of rest, analgesia, bracing, and early mobilization are recommended to prevent severe deconditioning.

Question 7686

Topic: 2. Trauma

A 25-year-old man sustains a severe pelvic crush injury. CT reveals a sacral fracture extending through the sacral foramina. According to the Denis classification, what zone is this fracture, and what is the approximate rate of neurologic injury associated with it?

. Zone I (Alar); 5%
. Zone II (Foraminal); 28%
. Zone III (Central canal); 57%
. Zone I (Alar); 28%
. Zone II (Foraminal); 57%

Correct Answer & Explanation

. Zone I (Alar); 5%

Explanation

Denis Zone II sacral fractures pass through the neural foramina. They are associated with a neurologic injury rate of approximately 28%, most commonly involving the L5 or S1 nerve roots.

Question 7687

Topic: 2. Trauma

A 60-year-old woman with osteoporosis presents with back pain after a fall. MRI shows an L2 burst fracture with retropulsion but no spinal cord signal change. Which Denis column(s) must be disrupted to classify a fracture as a burst fracture rather than a simple compression fracture?

. Anterior column only
. Middle column only
. Anterior and middle columns
. Middle and posterior columns
. Anterior, middle, and posterior columns

Correct Answer & Explanation

. Anterior column only

Explanation

According to the Denis three-column theory, a compression fracture involves only the anterior column, whereas a burst fracture involves failure of both the anterior and middle columns under axial loading.

Question 7688

Topic: 2. Trauma

A 22-year-old man sustains a seatbelt flexion-distraction (Chance) injury of the thoracolumbar spine in a motor vehicle collision. Which of the following associated injuries is most commonly found with this specific fracture pattern?

. Aortic dissection
. Pulmonary contusion
. Intra-abdominal hollow viscus injury
. Pelvic ring fracture
. Renal laceration

Correct Answer & Explanation

. Aortic dissection

Explanation

Chance fractures, which are flexion-distraction injuries commonly caused by lap seatbelts, have a high association (up to 50%) with intra-abdominal injuries, particularly hollow viscus (e.g., bowel) tears.

Question 7689

Topic: 2. Trauma

Which of the following factors is most strongly associated with a high rate of nonunion in Type II odontoid fractures treated with rigid cervical collar immobilization?

. Age less than 30 years
. Displacement greater than 5 mm
. Posterior displacement of 2 mm
. Associated C1 ring fracture
. Angulation of 5 degrees

Correct Answer & Explanation

. Age less than 30 years

Explanation

Risk factors for nonunion in Type II odontoid fractures include age >50 years, initial displacement >5 mm, angulation >10 degrees, and delayed treatment.

Question 7690

Topic: 2. Trauma

A 35-year-old female sustains a pelvic ring injury and a sacral fracture following a fall from height. CT imaging shows the fracture line passes medial to the sacral foramina, involving the central sacral canal. According to the Denis classification of sacral fractures, what zone is involved, and what is the approximate risk of associated neurologic injury?

. Zone 1, <5% risk
. Zone 2, 25% risk
. Zone 3, >50% risk
. Zone 1, 50% risk
. Zone 3, 10% risk

Correct Answer & Explanation

. Zone 1, <5% risk

Explanation

Denis Zone 3 sacral fractures involve the central sacral canal (medial to the neural foramina). Because they directly compromise the cauda equina, they carry the highest rate of neurologic injury, frequently exceeding 50%.

Question 7691

Topic: 2. Trauma

A 30-year-old man presents after a motorcycle crash with a Denis zone 3 sacral fracture. He has loss of bowel and bladder control and perineal numbness. What is the likelihood of neurologic injury with this specific fracture zone compared to zones 1 and 2?

. Lower than zone 1 and zone 2
. Equal to zone 1
. Equal to zone 2
. Highest among all zones (approximately 60%)
. Negligible risk

Correct Answer & Explanation

. Lower than zone 1 and zone 2

Explanation

Denis zone 3 sacral fractures involve the central sacral canal and carry the highest rate of neurologic injury (up to 60%), frequently presenting with bowel, bladder, and sexual dysfunction due to sacral nerve root involvement.

Question 7692

Topic: 2. Trauma

An 80-year-old female presents with severe localized back pain after coughing. X-rays reveal a new L1 anterior wedge compression fracture. After 6 weeks of conservative management (bracing, analgesics), her pain remains VAS 8/10. What is the most appropriate next step?

. Anterior corpectomy and fusion
. Posterior instrumented fusion from T11 to L3
. Vertebroplasty or kyphoplasty
. Continuous epidural steroid injections
. Long-term opioid therapy

Correct Answer & Explanation

. Anterior corpectomy and fusion

Explanation

Vertebroplasty or balloon kyphoplasty is indicated for osteoporotic vertebral compression fractures that fail conservative management (usually after 4-6 weeks) and are characterized by severe, localized pain. It provides rapid pain relief through cement stabilization.

Question 7693

Topic: 2. Trauma

According to randomized controlled trials (e.g., Wood et al.) evaluating the treatment of stable thoracolumbar burst fractures without neurologic deficit, how do the outcomes of TLSO bracing compare to no bracing?

. Bracing significantly improves long-term sagittal alignment
. Bracing reduces the rate of adjacent segment degeneration
. No bracing yields equivalent functional and radiographic outcomes compared to bracing
. Bracing significantly decreases the rate of late neurologic decline
. No bracing leads to a higher rate of symptomatic nonunion

Correct Answer & Explanation

. Bracing significantly improves long-term sagittal alignment

Explanation

Level I evidence from Wood et al. demonstrated that for stable thoracolumbar burst fractures, conservative management with early mobilization without a brace provides equivalent clinical and radiographic outcomes compared to TLSO bracing.

Question 7694

Topic: 2. Trauma

The Load Sharing Classification (McCormack) of spine fractures is primarily utilized to predict the failure of which surgical intervention?

. Nonoperative management with a TLSO brace
. Posterior short-segment pedicle screw fixation alone
. Anterior corpectomy and fusion
. Percutaneous vertebroplasty
. Long-segment instrumented posterior fusion

Correct Answer & Explanation

. Nonoperative management with a TLSO brace

Explanation

The Load Sharing Classification assesses vertebral body comminution, fragment apposition, and kyphosis to determine if posterior short-segment fixation alone will fail, indicating a need for anterior column structural reconstruction.

Question 7695

Topic: 2. Trauma

A 19-year-old woman is a restrained passenger in a high-speed motor vehicle collision. She sustains a severe flexion-distraction injury of L2. Which of the following associated injuries must be evaluated with a high index of suspicion?

. Aortic transection
. Diaphragmatic rupture
. Hollow viscus intra-abdominal injury
. Renal artery thrombosis
. Pelvic ring disruption

Correct Answer & Explanation

. Aortic transection

Explanation

Flexion-distraction (Chance-type) fractures occur frequently in seatbelt-restrained passengers. They have a high association (up to 40%) with intra-abdominal injuries, particularly hollow viscus injuries like bowel perforations.

Question 7696

Topic: 2. Trauma

A 28-year-old woman is involved in a severe motor vehicle collision. Radiographs demonstrate a fracture through the pedicles, transverse processes, and posterior vertebral body of L1. The mechanism of injury is predominantly:

. Axial loading
. Flexion-distraction
. Hyper-extension
. Lateral compression
. Rotational shear

Correct Answer & Explanation

. Axial loading

Explanation

A fracture line extending horizontally through the posterior elements (pedicles, transverse processes) and into the vertebral body is characteristic of a Chance fracture. This pattern is caused by a flexion-distraction mechanism.

Question 7697

Topic: Lower Extremity Trauma

A 6-year-old girl presents with torticollis following an upper respiratory infection. A dynamic CT scan reveals atlantoaxial rotatory subluxation with an anterior displacement of the atlas of 4 mm on the axis. According to the Fielding and Hawkins classification, what type of injury is this?

. Type I
. Type II
. Type III
. Type IV
. Type V

Correct Answer & Explanation

. Type I

Explanation

Fielding and Hawkins Type II describes a rotatory subluxation with 3-5 mm of anterior displacement, indicating deficiency of the transverse ligament. Type I has no anterior displacement (<3 mm), and Type III has >5 mm of displacement.

Question 7698

Topic: 2. Trauma

A 72-year-old male sustains a Type II odontoid fracture. He is being evaluated for conservative management in a halo vest. Which of the following factors represents the most significant risk factor for nonunion with nonoperative treatment?

. Anterior rather than posterior displacement
. Initial fracture displacement greater than 5 mm
. Concomitant C1 arch fracture
. Angulation less than 10 degrees
. Patient age less than 65 years

Correct Answer & Explanation

. Anterior rather than posterior displacement

Explanation

The most significant risk factors for nonunion in Type II odontoid fractures are an initial displacement greater than 5 mm, angulation greater than 10 degrees, and age greater than 50-65 years. These factors strongly predict failure of halo vest immobilization.

Question 7699

Topic: 2. Trauma

According to the Denis classification of sacral fractures, fractures extending through which zone are associated with the highest incidence of severe neurologic injury, including bowel and bladder dysfunction?

. Zone 1
. Zone 2
. Zone 3
. Zone 4
. Zone 5

Correct Answer & Explanation

. Zone 1

Explanation

Denis Zone 3 sacral fractures involve the central sacral canal. Because they involve the sacral nerve roots regulating sphincter function, they carry the highest risk of neurologic injury (up to 57%), including bowel, bladder, and sexual dysfunction.

Question 7700

Topic: Pelvic & Acetabular Trauma

Diffuse Idiopathic Skeletal Hyperostosis (DISH) is characterized by flowing ossification along the anterolateral aspect of the spine. According to the Resnick and Niwayama criteria, involvement of how many contiguous vertebral bodies is required to definitively diagnose DISH?

. 2
. 3
. 4
. 5
. 6

Correct Answer & Explanation

. 2

Explanation

The Resnick and Niwayama criteria for DISH require flowing ossification over at least four contiguous vertebral bodies. Additional criteria include relative preservation of disc height and the absence of sacroiliac joint erosion or apophyseal joint ankylosis.

Test Yourself

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

On this Page