Menu

2. Trauma MCQs

Practice Set 364 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 7261

Topic: 2. Trauma

A 72-year-old man sustains a reverse obliquity intertrochanteric femur fracture. Which of the following fixation constructs provides the highest biomechanical stability for this fracture pattern?

. Sliding hip screw with a 135-degree sideplate
. Sliding hip screw with a 150-degree sideplate
. Cephalomedullary nail
. Multiple cancellous lag screws
. Proximal femoral locking plate

Correct Answer & Explanation

. Sliding hip screw with a 135-degree sideplate

Explanation

Cephalomedullary nails provide superior biomechanical stability for reverse obliquity intertrochanteric fractures due to their intramedullary load-sharing design. Sliding hip screws are contraindicated as they allow the femoral shaft to medialize excessively in this fracture pattern.

Question 7262

Topic: 2. Trauma
A 35-year-old man sustains a vertically oriented (Pauwels type III) displaced femoral neck fracture. What is the most appropriate internal fixation construct to minimize shear forces and prevent varus collapse?
. Three parallel cancellous screws placed in an inverted triangle
. Three parallel cancellous screws placed in a standard triangle
. A dynamic hip screw (DHS) with a derotational screw
. A cephalomedullary nail
. A bipolar hemiarthroplasty

Correct Answer & Explanation

. A dynamic hip screw (DHS) with a derotational screw

Explanation

For young patients with vertically oriented (Pauwels type III) femoral neck fractures, a dynamic hip screw (fixed-angle device) provides superior biomechanical resistance to shear forces compared to multiple cancellous screws. A derotational screw is often added for additional rotational control.

Question 7263

Topic: 2. Trauma

In a proximal third subtrochanteric femur fracture, the proximal fragment is typically displaced into which of the following positions?

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

Correct Answer & Explanation

. Flexion, adduction, and internal rotation

Explanation

In a subtrochanteric fracture, the proximal fragment is flexed by the iliopsoas, abducted by the gluteus medius and minimus, and externally rotated by the short external rotators. Recognition of these deforming forces is critical for achieving a successful closed reduction prior to nailing.

Question 7264

Topic: 2. Trauma

A 40-year-old woman undergoes closed reduction and percutaneous pinning for a displaced femoral neck fracture. Which of the following factors is most predictive of subsequent osteonecrosis of the femoral head?

. Delay to surgery greater than 12 hours
. Initial degree of fracture displacement
. Non-anatomic reduction
. Use of a fourth cancellous screw
. Patient age

Correct Answer & Explanation

. Delay to surgery greater than 12 hours

Explanation

The initial degree of displacement (Garden classification) is the most significant prognostic factor for the development of osteonecrosis after a femoral neck fracture. While an anatomic reduction is crucial to prevent nonunion, initial vascular disruption is tied directly to the trauma's severity.

Question 7265

Topic: 2. Trauma

A 78-year-old woman presents with thigh pain and inability to bear weight after a mechanical fall. Radiographs demonstrate a fracture around her cemented femoral stem just distal to the lesser trochanter. The stem has subsided 1.5 cm and there is a visible cement mantle fracture. What is the most appropriate surgical treatment?

. Open reduction internal fixation (ORIF) with a locking plate
. ORIF with cerclage cables and cortical strut allografts
. Revision to a standard length cemented stem
. Revision to a long fully porous-coated or fluted tapered stem
. Skeletal traction for 6 weeks

Correct Answer & Explanation

. Open reduction internal fixation (ORIF) with a locking plate

Explanation

This is a Vancouver B2 periprosthetic fracture, defined as a fracture around the stem with a loose implant but good bone stock. The standard treatment is revision of the femoral component using a long cementless stem that bypasses the fracture by at least two cortical diameters.

Question 7266

Topic: 2. Trauma

A 68-year-old man presents with an unstable intertrochanteric femur fracture.

A cephalomedullary nail is planned. To minimize the risk of hardware cut-out, what is the ideal tip-apex distance (TAD)?

. Less than 15 mm
. Less than 25 mm
. Less than 35 mm
. Greater than 25 mm
. Greater than 35 mm

Correct Answer & Explanation

. Less than 15 mm

Explanation

A tip-apex distance (TAD) of less than 25 mm is the most critical biomechanical and radiographic factor in preventing lag screw cut-out. This rule applies to both sliding hip screws and cephalomedullary nails used for intertrochanteric fractures.

Question 7267

Topic: 2. Trauma
A 30-year-old male sustains a high-energy Pauwels type III (vertical) femoral neck fracture. He is medically stable. Which of the following biomechanical constructs provides the most stable fixation for this specific fracture pattern?
. Three parallel screws in an inverted triangle configuration
. Three parallel screws in a standard triangle configuration
. A sliding hip screw with an anti-rotation screw
. Two parallel cannulated screws
. A flexible intramedullary nail

Correct Answer & Explanation

. A sliding hip screw with an anti-rotation screw

Explanation

Pauwels type III (vertical) fractures experience high shear forces and have higher failure rates with traditional cannulated screws. A sliding hip screw combined with a derotational screw provides superior biomechanical stability and higher loads to failure for highly vertical femoral neck fractures.

Question 7268

Topic: 2. Trauma

A 25-year-old man sustains a vertically oriented (Pauwels type III) femoral neck fracture. Biomechanical studies indicate which of the following constructs provides the greatest stability against shear forces for this fracture pattern?

. Three parallel cancellous lag screws
. Sliding hip screw with a derotation screw
. Dynamic condylar screw
. Cephalomedullary nail
. Non-locking proximal femoral plate

Correct Answer & Explanation

. Three parallel cancellous lag screws

Explanation

Pauwels type III fractures have high shear forces. A fixed-angle device, such as a sliding hip screw with a derotation screw, provides superior biomechanical stability compared to multiple cancellous screws.

Question 7269

Topic: 2. Trauma

A 78-year-old woman with an intertrochanteric hip fracture is found to have a highly comminuted lateral wall on pre-operative imaging. Which fixation method is most appropriate?

. Sliding hip screw (DHS)
. Multiple cancellous screws
. Cephalomedullary nail
. Proximal femoral locking plate
. Bipolar hemiarthroplasty

Correct Answer & Explanation

. Sliding hip screw (DHS)

Explanation

An intact lateral wall is critical for the success of a sliding hip screw. When the lateral wall is comminuted or fractured, a cephalomedullary nail is indicated to prevent excessive lateral slide and medialization of the femoral shaft.

Question 7270

Topic: 2. Trauma

A 25-year-old man sustains a completely displaced, vertically oriented femoral neck fracture (Pauwels type III). Which of the following fixation constructs offers the highest biomechanical stability for this specific fracture pattern?

. Three parallel cancellous screws
. Sliding hip screw with an anti-rotation screw
. Short cephalomedullary nail with a single screw
. Fixed-angle 95-degree blade plate
. Hemiarthroplasty

Correct Answer & Explanation

. Three parallel cancellous screws

Explanation

For high-shear, vertically oriented (Pauwels type III) femoral neck fractures in young adults, a sliding hip screw with a derotation screw provides superior biomechanical stability. It better resists vertical shear forces compared to three parallel cancellous screws.

Question 7271

Topic: 2. Trauma

Medical optimization and surgical treatment of an acute hip fracture in a geriatric patient should ideally be completed within what timeframe to most significantly reduce 30-day and 1-year mortality rates?

. 12 hours
. 24 hours
. 48 hours
. 72 hours
. 96 hours

Correct Answer & Explanation

. 12 hours

Explanation

Extensive literature and current AAOS guidelines strongly support that surgical fixation of geriatric hip fractures within 48 hours significantly decreases mortality, complication rates, and length of hospital stay.

Question 7272

Topic: 2. Trauma



During the insertion of a cemented femoral stem for a femoral neck fracture, the patient develops sudden hypoxia, hypotension, and right heart strain. What is the most important step a surgeon can take during canal preparation to minimize the risk of this specific complication?

. Under-reaming the femoral canal by 2 millimeters
. Lavage and thorough drying of the intramedullary canal prior to cementation
. Using exclusively high-viscosity cement in a doughy state
. Rapid and forceful insertion of the prosthesis
. Avoiding the use of a distal cement restrictor

Correct Answer & Explanation

. Under-reaming the femoral canal by 2 millimeters

Explanation

Bone cement implantation syndrome (BCIS) is caused by the embolization of marrow fat and debris due to increased intramedullary pressure. Copious pulsatile lavage, drying the canal, and using a distal restrictor help reduce this pressure and embolization risk.

Question 7273

Topic: 2. Trauma

A 75-year-old female presents with an intertrochanteric femur fracture. Radiographs demonstrate an intact posteromedial cortex but a lateral wall thickness of 18 mm. Which of the following is the most appropriate implant choice to minimize the risk of construct failure?

. Sliding hip screw (DHS)
. Cephalomedullary nail
. Proximal femoral locking plate
. Cannulated screws
. Bipolar hemiarthroplasty

Correct Answer & Explanation

. Sliding hip screw (DHS)

Explanation

A lateral wall thickness of less than 20.5 mm in an intertrochanteric fracture is a strong predictor for lateral wall fracture during surgery. A cephalomedullary nail is preferred over a sliding hip screw to prevent excessive collapse and construct failure.

Question 7274

Topic: 2. Trauma

A 68-year-old woman with a 10-year history of alendronate use presents with thigh pain and sustains a low-energy subtrochanteric femur fracture. Radiographs reveal a transverse fracture with lateral cortical beaking. Which of the following surgical principles is critical in her management?

. Use of a sliding hip screw to allow dynamic compression
. Reaming the medullary canal and using a full-length cephalomedullary nail
. Fixation with a proximal femoral locking plate without bone grafting
. Immediate full weight-bearing postoperatively
. Short intramedullary nailing to preserve distal endosteal blood supply

Correct Answer & Explanation

. Use of a sliding hip screw to allow dynamic compression

Explanation

Atypical femur fractures associated with bisphosphonate use typically have poor bone healing due to suppressed remodeling. A full-length cephalomedullary nail after reaming is recommended to protect the entire femur and provide stable fixation.

Question 7275

Topic: 2. Trauma

A 78-year-old male with multiple medical comorbidities sustains a displaced femoral neck fracture. When counseling the family regarding prognosis, what is the approximate expected 1-year mortality rate for patients over age 65 following a hip fracture?

. 2-5%
. 8-12%
. 20-30%
. 45-55%
. 60-70%

Correct Answer & Explanation

. 2-5%

Explanation

The 1-year mortality rate following a hip fracture in the elderly population is consistently reported in the literature to be between 20% and 30%, largely driven by underlying medical comorbidities.

Question 7276

Topic: 2. Trauma

A 72-year-old male with an intertrochanteric femur fracture is treated with a sliding hip screw (DHS). Three months postoperatively, radiographs show cutout of the lag screw through the superior femoral head. Which of the following technical factors is most highly associated with this mode of failure?

. Use of a 135-degree angle plate instead of a 150-degree plate
. Tip-apex distance (TAD) greater than 25 mm
. Placement of the screw in the inferior half of the femoral head
. Failure to use an anti-rotation screw
. Overtightening of the compression screw

Correct Answer & Explanation

. Use of a 135-degree angle plate instead of a 150-degree plate

Explanation

Baumgaertner et al. demonstrated that a Tip-Apex Distance (TAD) greater than 25 mm is the strongest predictor of lag screw cutout in the treatment of intertrochanteric fractures.

Question 7277

Topic: 2. Trauma

A 72-year-old woman sustains a reverse obliquity intertrochanteric femur fracture (OTA 31-A3). Based on current biomechanical studies and clinical evidence, which of the following constructs provides the most stable fixation with the lowest rate of hardware failure?

. Sliding hip screw with a 135-degree side plate
. Cephalomedullary nail
. Proximal femoral locking plate
. Multiple parallel cancellous screws
. Bipolar hemiarthroplasty

Correct Answer & Explanation

. Sliding hip screw with a 135-degree side plate

Explanation

Reverse obliquity fractures are highly unstable and have high failure rates with sliding hip screws because the fracture line is parallel to the trajectory of the sliding screw. Cephalomedullary nails provide superior biomechanical stability by medially displacing the weight-bearing axis and limiting medial shaft displacement.

Question 7278

Topic: 2. Trauma

A 32-year-old man sustains a completely displaced, vertically oriented femoral neck fracture (Pauwels Type III). What is the optimal fixation construct to minimize the risk of varus collapse, shear failure, and nonunion?

. Three parallel cancellous screws placed in an inverted triangle
. Sliding hip screw combined with an anti-rotation screw
. Intramedullary cephalomedullary nail
. Primary total hip arthroplasty
. Cannulated screws placed in a linear vertical pattern

Correct Answer & Explanation

. Three parallel cancellous screws placed in an inverted triangle

Explanation

Pauwels Type III fractures experience extremely high shear forces, frequently leading to varus collapse and nonunion when treated with simple parallel screws. A sliding hip screw, supplemented with a derotational cancellous screw, provides superior biomechanical resistance against these vertical shear forces.

Question 7279

Topic: 2. Trauma

A 45-year-old active male presents with an intertrochanteric hip fracture. Open reduction and internal fixation with a sliding hip screw is planned. To minimize the risk of screw cut-out, what is the ideal tip-apex distance (TAD)?

. Less than 15 mm
. Less than 25 mm
. Less than 35 mm
. Less than 45 mm
. Greater than 25 mm

Correct Answer & Explanation

. Less than 15 mm

Explanation

A tip-apex distance (TAD) of less than 25 mm has been shown to significantly reduce the risk of lag screw cut-out in the treatment of intertrochanteric fractures.

Question 7280

Topic: 2. Trauma



Figure 6 shows the radiograph of an 82-year-old man who sustained a Vancouver B2 periprosthetic femur fracture around a cemented femoral stem. What is the most appropriate surgical management?

. Open reduction internal fixation with a locking plate
. Revision to a long, fully porous-coated uncemented stem
. Revision to a long cemented stem
. Cortical strut allografts alone
. Nonoperative management with a brace

Correct Answer & Explanation

. Open reduction internal fixation with a locking plate

Explanation

A Vancouver B2 fracture is characterized by a loose stem with adequate bone stock. The standard of care is revision to a long uncemented stem, bypassing the fracture by two cortical diameters.

Test Yourself

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

On this Page