Menu

2. Trauma MCQs

Practice Set 313 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 6241

Topic: 2. Trauma
A 45-year-old man sustains a Grade IIIB open tibia fracture from a farming accident involving heavy soil contamination. In addition to emergent surgical debridement, which of the following prophylactic antibiotic regimens is most appropriate?
. First-generation cephalosporin alone
. First-generation cephalosporin and an aminoglycoside
. First-generation cephalosporin, an aminoglycoside, and penicillin
. Fluoroquinolone alone
. Vancomycin and ceftriaxone

Correct Answer & Explanation

. First-generation cephalosporin, an aminoglycoside, and penicillin

Explanation

For a Gustilo-Anderson Grade III open fracture, standard antibiotic prophylaxis includes a first-generation cephalosporin and an aminoglycoside to cover both Gram-positive and Gram-negative organisms. Because this is a farm injury with soil contamination, there is a significantly increased risk for clostridial infection (gas gangrene); thus, high-dose penicillin should be added to the regimen for anaerobic coverage.

Question 6242

Topic: 2. Trauma

A 22-year-old male athlete falls on his outstretched hand and sustains a scaphoid fracture. Which of the following fracture characteristics is associated with the highest risk of nonunion and avascular necrosis?

. Proximal pole location
. Distal pole location
. Waist location, nondisplaced
. Tuberosity fracture
. Concomitant distal radius fracture

Correct Answer & Explanation

. Proximal pole location

Explanation

The blood supply to the scaphoid is predominantly retrograde, entering the distal portion of the bone and perfusing the proximal pole. Fractures of the proximal pole disrupt this precarious blood supply, leading to a high rate of avascular necrosis and nonunion. Fractures of the distal pole and tuberosity have an excellent blood supply and a high rate of union with conservative management.

Question 6243

Topic: 2. Trauma

A 42-year-old man sustains a severe closed tibial shaft fracture. He undergoes reamed intramedullary nailing. Which of the following intraoperative techniques is most effective in minimizing the elevation of intramedullary pressure and subsequent risk of fat embolism?

. Rapid advancement of the reamer
. Using a reamer with shallow flutes
. Using dull reamers to minimize cortical damage
. Slow advancement of a sharp reamer with deep flutes
. Use of a tourniquet during reaming

Correct Answer & Explanation

. Slow advancement of a sharp reamer with deep flutes

Explanation

The use of sharp reamers with deep flutes, combined with slow and steady advancement, allows for optimal clearance of reamings and minimizes both heat generation and peaks in intramedullary pressure, effectively reducing the risk of fat embolism.

Question 6244

Topic: 2. Trauma

A 26-year-old male presents with an isolated, closed, displaced transverse fracture of the femoral shaft following a motorcycle collision. He is hemodynamically stable. Antegrade intramedullary nailing is planned. What is the most critical intraoperative factor in preventing a nonunion?

. Use of an unreamed nail
. Avoiding a fracture gap greater than 2 mm
. Use of a trochanteric entry point instead of piriformis fossa
. Leaving the tourniquet deflated
. Routine bone grafting of the fracture site

Correct Answer & Explanation

. Avoiding a fracture gap greater than 2 mm

Explanation

A residual fracture gap greater than 2 mm has been shown to be the most significant independent predictor of nonunion following intramedullary nailing of femoral shaft fractures. Reamed nails have actually demonstrated a lower rate of nonunion compared to unreamed nails in robust literature.

Question 6245

Topic: 2. Trauma
A 35-year-old man sustains a displaced Hawkins type III talar neck fracture. Which of the following surgical strategies provides the best biomechanical stability and allows for optimal visualization of the reduction?
. A single anterolateral approach with rigid plate fixation
. A single anteromedial approach with crossed lag screws
. Dual anteromedial and anterolateral approaches with screw fixation
. A posterior approach with posterior-to-anterior screw fixation
. Medial malleolar osteotomy with K-wire fixation

Correct Answer & Explanation

. Dual anteromedial and anterolateral approaches with screw fixation

Explanation

Hawkins type III talar neck fractures are highly displaced and often comminuted. Dual approaches (anteromedial and anterolateral) are necessary to accurately assess and reduce the medial and lateral columns of the talar neck. Biomechanically, screw fixation is best when multiple columns are stabilized.

Question 6246

Topic: 2. Trauma

A 68-year-old woman with a history of severe osteoporosis is treated with a locking plate for a 3-part proximal humerus fracture. Four weeks postoperatively, radiographs demonstrate varus collapse of the humeral head and screw cutout. Which of the following technical errors during the index procedure is most likely responsible for this complication?

. Failure to use a deltopectoral approach
. Inadequate restoration of the medial calcar and omission of inferomedial calcar screws
. Placement of the plate too inferiorly on the shaft
. Over-reduction of the greater tuberosity
. Use of a tension band suture for the tuberosities

Correct Answer & Explanation

. Inadequate restoration of the medial calcar and omission of inferomedial calcar screws

Explanation

In locked plating of proximal humerus fractures, the lack of medial support (comminuted or unreduced medial calcar) is the primary cause of varus collapse. Placement of inferomedial calcar screws in the locking plate is critical to provide mechanical support against varus deforming forces.

Question 6247

Topic: Pelvic & Acetabular Trauma
A 25-year-old man arrives at the trauma center hemodynamically unstable with an anteroposterior compression type III (APC-III) pelvic ring injury. A pelvic binder is applied, and he receives massive transfusion protocol. His FAST exam is negative, but he remains hypotensive. What is the most likely anatomic source of his ongoing pelvic hemorrhage?
. Superior gluteal artery
. Internal pudendal artery
. Obturator artery
. Sacral venous plexus
. External iliac vein

Correct Answer & Explanation

. Sacral venous plexus

Explanation

While arterial bleeding (such as from the superior gluteal artery or internal pudendal artery) can cause rapid exsanguination, the presacral and perivesical venous plexuses, along with cancellous bone bleeding, account for 80-90% of all pelvic hemorrhage in major pelvic ring injuries.

Question 6248

Topic: 2. Trauma

A 22-year-old male sustains a pelvic fracture in a motor vehicle accident. The AP pelvic radiograph demonstrates disruption of both the iliopectineal and ilioischial lines on the right side. The obturator ring is intact. Which of the following Judet-Letournel classifications best describes this fracture pattern?

. Anterior column fracture
. Posterior column fracture
. Transverse fracture
. T-type fracture
. Both-column fracture

Correct Answer & Explanation

. Transverse fracture

Explanation

A transverse acetabular fracture involves both the anterior and posterior columns, dividing the innominate bone into upper and lower halves. Radiographically, this disrupts both the iliopectineal line (anterior column) and ilioischial line (posterior column). The intact obturator ring differentiates it from a T-type or both-column fracture.

Question 6249

Topic: 2. Trauma

The Sanders classification is utilized for preoperative planning in calcaneus fractures. Which of the following imaging modalities and views is essential for applying this classification system?

. Harris axial radiograph view
. Broden's radiograph view
. Lateral radiograph of the foot
. Coronal computed tomography (CT) images
. Axial computed tomography (CT) images

Correct Answer & Explanation

. Coronal computed tomography (CT) images

Explanation

The Sanders classification for calcaneus fractures is based exclusively on the number and location of articular fracture lines extending through the posterior facet as seen on coronal CT images. It dictates the surgical approach and offers prognostic value.

Question 6250

Topic: 2. Trauma

A 38-year-old male falls from a ladder and sustains an isolated, closed, displaced midshaft clavicle fracture. Which of the following is considered an absolute indication for operative fixation?

. 100% displacement of the fracture fragments
. 2 cm of shortening
. Open fracture
. Z-deformity with comminution
. Concomitant displaced rib fractures

Correct Answer & Explanation

. Open fracture

Explanation

Absolute indications for operative fixation of a clavicle fracture include open fractures, neurovascular compromise, and severe skin tenting that acutely threatens skin viability. Displacement, shortening, comminution (Z-deformity), and floating shoulder are relative indications.

Question 6251

Topic: 2. Trauma

A 40-year-old man sustains an extra-articular distal third tibia fracture. Intramedullary nailing is planned. To prevent the most common malalignment associated with this specific fracture pattern during nailing, which of the following techniques should be primarily employed?

. Use of an unreamed nail to preserve endosteal blood supply
. Placing the starting point slightly lateral and extending the knee during nailing
. Using a medial entry point and a fibular plate
. Blocking screws (Poller screws) placed concave to the expected deformity
. Routine use of a tourniquet to improve visualization

Correct Answer & Explanation

. Blocking screws (Poller screws) placed concave to the expected deformity

Explanation

Distal third tibia fractures are notoriously prone to malalignment (particularly valgus and procurvatum deformities) due to the wide metaphysis and lack of tight endosteal fit for the nail. Blocking screws (Poller screws) placed on the concave side of the expected deformity narrow the medullary canal, help direct the nail centrally, and prevent angular malalignment.

Question 6252

Topic: 2. Trauma
A 45-year-old female presents with a closed, displaced intra-articular calcaneus fracture (Sanders Type III). The surgeon is considering an extensile lateral approach for open reduction and internal fixation. Which of the following is considered an absolute contraindication to utilizing this specific approach?
. Smoking 1 pack of cigarettes per day
. Poorly controlled diabetes mellitus with peripheral neuropathy
. The presence of a fracture blister over the medial hindfoot
. Time from injury greater than 14 days
. Concurrent lumbar burst fracture

Correct Answer & Explanation

. Poorly controlled diabetes mellitus with peripheral neuropathy

Explanation

The extensile lateral approach for calcaneus fractures carries a significant risk of wound complications. Absolute contraindications for this approach include poorly controlled diabetes mellitus with peripheral neuropathy, severe peripheral vascular disease, and active infection. Smoking is a strong relative contraindication due to increased wound healing risks. Fracture blisters dictate the timing of surgery (waiting for re-epithelialization) rather than acting as an absolute contraindication to the approach.

Question 6253

Topic: 2. Trauma

A 30-year-old construction worker sustains a severe pilon fracture and is initially treated with a spanning external fixator. At 14 days, the soft tissue envelope has improved and he undergoes definitive ORIF via an anterolateral approach to the distal tibia. During the superficial dissection, which of the following structures is most at risk of iatrogenic injury?

. Saphenous nerve
. Sural nerve
. Deep peroneal nerve
. Superficial peroneal nerve
. Tibial nerve

Correct Answer & Explanation

. Superficial peroneal nerve

Explanation

The anterolateral approach to the distal tibia is commonly used for pilon fractures. The superficial peroneal nerve crosses the surgical interval from lateral to medial as it descends toward the foot and is at high risk of iatrogenic injury. The deep peroneal nerve and anterior tibial artery are located deeper and more medially between the tibialis anterior and extensor hallucis longus.

Question 6254

Topic: Pelvic & Acetabular Trauma

During the percutaneous placement of an S1 transiliac-transsacral screw for a posterior pelvic ring injury, the surgeon must be aware of sacral dysmorphism. Which of the following is a radiographic sign of sacral dysmorphism that indicates the S1 osseous corridor may be restricted or unsafe?

. Colinear upper sacral neural foramina on the outlet view
. Recessed upper sacrum within the pelvis
. An acute upward angulation of the sacral ala
. Absence of mammillary processes at the sacroiliac joint
. Symmetrical S1 neural foramina on the inlet view

Correct Answer & Explanation

. An acute upward angulation of the sacral ala

Explanation

Sacral dysmorphism refers to anatomic variations that make standard placement of S1 iliosacral screws difficult or unsafe. Radiographic signs include an acute upward angulation of the sacral ala (alar slope), a non-recessed (flush) upper sacrum, tongue-in-groove sacroiliac joints, non-circular (often teardrop-shaped) upper sacral neural foramina on the outlet view, and residual upper sacral disc spaces. These features result in a narrow, oblique osseous corridor.

Question 6255

Topic: 2. Trauma

A 22-year-old male sustains a low-velocity handgun wound to the mid-thigh. Radiographs reveal a comminuted midshaft femur fracture. The patient has a normal neurovascular examination and the wounds are clean with 5 mm entry and exit holes. What is the most appropriate definitive management?

. Immediate formal deep surgical debridement of the wound tracts and external fixation
. Local wound care, short-course IV antibiotics, and immediate unreamed intramedullary nailing
. Local wound care, short-course IV antibiotics, and immediate reamed intramedullary nailing
. Skeletal traction and IV antibiotics for 7 days, followed by delayed intramedullary nailing
. Immediate formal deep surgical debridement of the wound tracts and plate fixation

Correct Answer & Explanation

. Local wound care, short-course IV antibiotics, and immediate reamed intramedullary nailing

Explanation

Low-velocity gunshot wounds resulting in diaphyseal femur fractures are generally treated similarly to closed fractures, provided there is no gross contamination or severe soft tissue compromise. Immediate reamed intramedullary nailing after local wound care (superficial debridement of the entry/exit wounds) and short-course intravenous antibiotics has been shown to be safe and highly effective. Formal deep surgical tract debridement is unnecessary and increases morbidity.

Question 6256

Topic: 2. Trauma

A 65-year-old female sustains a valgus-impacted proximal humerus fracture. The medial calcar hinge is completely disrupted. According to recent quantitative anatomical studies, which of the following blood vessels provides the primary vascular supply to the humeral head articular segment?

. Anterior circumflex humeral artery
. Posterior circumflex humeral artery
. Thoracoacromial artery
. Suprascapular artery
. Subscapular artery

Correct Answer & Explanation

. Posterior circumflex humeral artery

Explanation

Recent quantitative anatomical studies (Hettrich et al.) have demonstrated that the posterior circumflex humeral artery (PCHA) provides the majority (approximately 64%) of the blood supply to the humeral head, predominantly perfusing the posteroinferior, posterosuperior, and central portions. The anterior circumflex humeral artery (ACHA), historically taught as the primary supplier via the arcuate artery, actually contributes significantly less. Preservation of the PCHA is critical during surgical intervention.

Question 6257

Topic: 2. Trauma

A 40-year-old male presents with a closed midshaft clavicle fracture with 100% displacement and 2.5 cm of shortening. Compared to nonoperative management with a sling, what is the most significant clinical advantage of open reduction and internal fixation for this patient?

. Decreased risk of deep infection
. Decreased rate of nonunion
. Improved long-term cosmetic outcome
. Lower overall cost of treatment
. Reduced risk of delayed neurovascular injury

Correct Answer & Explanation

. Decreased rate of nonunion

Explanation

Historically, nonoperative management of midshaft clavicle fractures carried a low assumed nonunion rate. However, prospective trials (e.g., COTS) demonstrated that completely displaced, shortened (>2 cm) midshaft clavicle fractures have a nonunion rate of approximately 15% when treated nonoperatively. Open reduction and internal fixation significantly decreases the rate of nonunion to less than 2% and improves early functional outcomes, though it carries surgical risks such as hardware prominence.

Question 6258

Topic: 2. Trauma

A 35-year-old woman sustains a closed, isolated transverse fracture of the middle third of the humeral shaft. She is initially treated with a coaptation splint and transitioned to a functional fracture brace. Which of the following represents an absolute contraindication to continued nonoperative treatment with functional bracing?

. 15 degrees of anterior angulation
. 20 degrees of varus angulation
. 2.5 centimeters of shortening
. Inability to maintain acceptable alignment
. An initial radial nerve palsy

Correct Answer & Explanation

. Inability to maintain acceptable alignment

Explanation

Functional bracing (Sarmiento bracing) relies on soft tissue compression to maintain fracture alignment and has a high union rate for closed humeral shaft fractures. Acceptable alignment parameters include up to 20 degrees of anterior angulation, 30 degrees of varus angulation, and up to 3 centimeters of shortening. The inability to maintain these parameters is an absolute contraindication to continued bracing. Initial closed radial nerve palsy is not a contraindication, as most will spontaneously resolve.

Question 6259

Topic: Pelvic & Acetabular Trauma

A 50-year-old male is involved in a high-speed collision and sustains an APC II (anteroposterior compression) pelvic ring injury with widening of the symphysis pubis. If isolated internal fixation is planned for the anterior ring, which of the following statements regarding the biomechanics of symphyseal plating is correct?

. A multi-hole plate with locking screws provides significantly more stability than standard cortical screws in the symphysis
. Two-hole plates provide equivalent biomechanical stability to multi-hole plates for APC II injuries
. Symphyseal plating alone predictably restores the stability of the posterior sacroiliac complex in vertically unstable patterns
. Placement of a plate on the superior surface of the symphysis is biomechanically superior to anterior placement
. Symphyseal plates should be routinely removed at 6 months to prevent hardware failure

Correct Answer & Explanation

. Placement of a plate on the superior surface of the symphysis is biomechanically superior to anterior placement

Explanation

Biomechanical studies have consistently demonstrated that a plate placed on the superior surface of the symphysis pubis provides superior mechanical stability compared to an anteriorly placed plate. This is due to the thicker and denser bone available for screw purchase on the superior pubic rami, as well as an improved mechanical advantage against the deforming forces of the pelvic ring. Routine removal is not indicated unless symptomatic.

Question 6260

Topic: 2. Trauma

A 25-year-old man sustains a subtrochanteric femur fracture following a motor vehicle collision. During closed reduction and intramedullary nailing, the proximal fracture fragment is notoriously difficult to reduce due to the deforming forces of the attached musculature. Which of the following muscles is primarily responsible for the external rotation deformity of the proximal segment?

. Iliopsoas
. Gluteus medius
. Gluteus maximus
. Short external rotators
. Adductor longus

Correct Answer & Explanation

. Iliopsoas

Explanation

In a subtrochanteric femur fracture, the proximal fragment is subjected to distinct muscular deforming forces. It is typically flexed by the iliopsoas, abducted by the gluteus medius and minimus, and externally rotated by the short external rotators (piriformis, gemelli, obturator internus/externus, quadratus femoris). Understanding these deforming forces is critical for obtaining an anatomic reduction.

Test Yourself

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

On this Page