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 2621
Topic: 2. Trauma
A Segond fracture observed on an AP radiograph of the knee is pathognomonic for an anterior cruciate ligament tear. This fracture represents a bony avulsion of the lateral capsule and which specific structure?
Correct Answer & Explanation
. Anterolateral ligament
Explanation
A Segond fracture is a cortical avulsion off the proximal lateral tibia just distal to the joint line. It represents the avulsion of the anterolateral ligament (ALL) and the lateral capsule, strongly indicating an underlying ACL rupture.
Question 2622
Topic: 2. Trauma
An open diaphyseal tibial fracture presents with a 12 cm laceration and extensive periosteal stripping. Following debridement, there is adequate local soft tissue to cover the bone. What is the appropriate Gustilo-Anderson classification?
Correct Answer & Explanation
. Type IIIA
Explanation
Gustilo-Anderson Type IIIA fractures involve extensive soft tissue damage, a wound > 10 cm, or high-energy mechanisms, but retain adequate local soft tissue coverage for the fractured bone. Type IIIB would require a rotational or free flap for coverage.
Question 2623
Topic: 2. Trauma
In an awake patient, what is clinically recognized as the earliest and most sensitive physical exam finding indicative of evolving acute compartment syndrome?
Correct Answer & Explanation
. Pain with passive stretch of the involved muscles
Explanation
Pain out of proportion to the injury, specifically exacerbated by passive stretch of the muscles traversing the affected compartment, is the earliest and most sensitive sign of acute compartment syndrome. Pulselessness and paralysis are late, ominous findings indicating irreversible damage.
Question 2624
Topic: 2. Trauma
A 28-year-old male sustains a displaced basicervical femoral neck fracture. He undergoes closed reduction and internal fixation with three cancellous screws. Which of the following factors is most predictive of osteonecrosis of the femoral head in this patient?
Correct Answer & Explanation
. Initial degree of fracture displacement
Explanation
The initial degree of fracture displacement is the most significant prognostic factor for the development of osteonecrosis in young patients with femoral neck fractures. While anatomic reduction is critical to minimize nonunion risk, the initial vascular insult dictated by displacement primarily drives osteonecrosis.
Question 2625
Topic: 2. Trauma
A 45-year-old male sustains a Schatzker VI tibial plateau fracture. Which of the following complications is most specifically associated with this fracture pattern due to its high-energy mechanism?
Correct Answer & Explanation
. Acute compartment syndrome
Explanation
Schatzker VI tibial plateau fractures involve metaphyseal-diaphyseal dissociation and are caused by high-energy crush mechanisms, placing patients at an exceptionally high risk for acute compartment syndrome. Careful and repeated assessment of the compartments is mandatory.
Question 2626
Topic: 2. Trauma
A 30-year-old male sustains a closed tibia fracture and develops suspected acute compartment syndrome. His blood pressure is 120/80 mmHg. Intracompartmental pressure testing is performed. At what pressure threshold is a four-compartment fasciotomy clearly indicated?
Correct Answer & Explanation
. Compartment pressure within 30 mmHg of the diastolic blood pressure (Delta P < 30)
Explanation
The most reliable indicator for fasciotomy is the Delta P (diastolic blood pressure minus intracompartmental pressure). A Delta P of less than 30 mmHg represents inadequate tissue perfusion and is the accepted threshold indicating the need for emergent fasciotomy.
Question 2627
Topic: 2. Trauma
A 25-year-old man sustains a Pauwels type III femoral neck fracture. Biomechanically, what is the primary force that fixation constructs must overcome to prevent failure in this specific fracture pattern?
Correct Answer & Explanation
. Shear forces
Explanation
Pauwels type III femoral neck fractures have a fracture angle greater than 50 degrees from the horizontal. This vertical orientation subjects the fracture site primarily to high shear forces, which increases the risk of varus collapse and nonunion.
Question 2628
Topic: 2. Trauma
A 32-year-old man is admitted with a closed tibia fracture. Which of the following objective measurements is most indicative of acute compartment syndrome?
Correct Answer & Explanation
. Diastolic blood pressure minus compartment pressure < 30 mmHg
Explanation
Acute compartment syndrome is defined by a delta P (diastolic blood pressure minus intra-compartmental pressure) of less than or equal to 30 mmHg. This objective measurement is more reliable than absolute compartment pressures alone.
Question 2629
Topic: 2. Trauma
A trauma patient presents with an anteroposterior compression (APC) type III pelvic ring injury. A circumferential pelvic binder is applied. For maximum mechanical efficacy, the binder should be centered over which anatomic landmark?
Correct Answer & Explanation
. Greater trochanters
Explanation
To optimally reduce pelvic volume and control hemorrhage in open-book pelvic fractures, a pelvic binder or sheet must be centered directly over the greater trochanters. Placement higher over the iliac crests is less effective and may paradoxically widen the pelvis.
Question 2630
Topic: 2. Trauma
In a 25-year-old patient with a Pauwels type III femoral neck fracture, which fixation construct provides the greatest biomechanical stability against vertical shear forces?
Correct Answer & Explanation
. A sliding hip screw combined with an anti-rotation screw
Explanation
Pauwels III fractures have a high vertical shear angle, leading to a high rate of fixation failure. Fixed-angle devices like a sliding hip screw combined with a derotational screw offer superior resistance to these shear forces compared to multiple cannulated screws.
Question 2631
Topic: Upper Extremity Trauma
A 22-year-old collegiate pitcher presents with posteromedial elbow pain and lack of full extension. Radiographs show loose bodies in the posteromedial compartment and an olecranon osteophyte. What associated pathology must be carefully evaluated before proceeding with arthroscopic loose body removal and olecranon debridement?
Correct Answer & Explanation
. Ulnar collateral ligament (UCL) insufficiency
Explanation
Valgus extension overload causes posteromedial osteophytes and loose bodies due to repetitive impingement. Aggressive olecranon debridement without addressing concurrent UCL insufficiency can unmask and exacerbate severe medial instability.
Question 2632
Topic: Upper Extremity Trauma
In a 55-year-old heavy laborer with primary osteoarthritis of the elbow, loose bodies and osteophytes are most commonly symptomatic and surgically addressed in which of the following elbow compartments?
Correct Answer & Explanation
. Anterior (coronoid/radial fossa) and posterior (olecranon fossa)
Explanation
Primary elbow osteoarthritis in laborers typically presents with terminal extension and flexion loss. This is driven by osteophyte impingement and loose body formation in the olecranon fossa (posteriorly) and coronoid fossa (anteriorly), respectively.
Question 2633
Topic: 2. Trauma
A 35-year-old male presents after a high-speed motor vehicle collision with an open Gustilo-Anderson IIIB comminuted tibia shaft fracture and an ipsilateral closed femoral shaft fracture. He is hemodynamically stable after initial resuscitation. What is the most appropriate initial management strategy for the lower extremity injuries?
Correct Answer & Explanation
. Debridement and irrigation of the open tibia fracture, external fixation of the tibia, and definitive fixation of the femur.
Explanation
In a stable polytrauma patient with a 'floating knee' injury (ipsilateral femoral and tibial shaft fractures), initial management prioritizes damage control for open fractures and early stabilization of long bone fractures. The most critical and time-sensitive step is thorough debridement and irrigation of the open tibia fracture to prevent infection, which should be performed within 6-8 hours. Following debridement, external fixation provides temporary stabilization of the open tibia, allowing for soft tissue recovery and serial debridements if needed. For the ipsilateral closed femoral shaft fracture, definitive fixation (typically intramedullary nailing) is generally performed early in stable patients (often within 24-48 hours) to reduce the systemic inflammatory response and facilitate patient mobilization.
Question 2634
Topic: 2. Trauma
A 48-year-old male sustains a Schatzker VI tibial plateau fracture following a fall from height. Examination reveals a tense leg with pain out of proportion, especially on passive dorsiflexion of the toes. Distal pulses are palpable but weak. Which of the following is the most critical immediate concern in this patient?
Correct Answer & Explanation
. Assessment for compartment syndrome.
Explanation
Correct Answer: CA Schatzker VI tibial plateau fracture is a high-energy injury involving both tibial condyles, often with significant displacement and severe soft tissue trauma. This type of injury carries a substantial risk of acute compartment syndrome due to hemorrhage, edema, and muscle injury within the confined fascial compartments of the lower leg. The clinical presentation of a 'tense leg with pain out of proportion' to the injury, and especially pain on passive stretch (e.g., passive dorsiflexion of the toes, which stretches the anterior compartment muscles), despite palpable pulses, is highly suggestive of impending or established compartment syndrome. This is a surgical emergency requiring immediate fasciotomy to prevent irreversible muscle ischemia, nerve damage, and potential limb loss.Why other options are incorrect:A. Deep vein thrombosis prophylaxis:DVT prophylaxis is important in trauma patients but is not the most critical immediate concern when compartment syndrome is suspected.B. Evaluation for ipsilateral fibular head fracture:An ipsilateral fibular head fracture is a common associated injury with tibial plateau fractures and can indicate posterolateral corner instability or peroneal nerve injury, but it is not as acutely limb-threatening as compartment syndrome.D. Pre-operative templating for dual plating:This is a crucial step in surgical planning for definitive fixation but is not an immediate concern when a limb-threatening condition like compartment syndrome is suspected.E. Consultation for potential popliteal artery injury:Popliteal artery injury is a serious concern with high-energy knee trauma, and weak pulses warrant further investigation (e.g., ABI, CTA). However, the constellation of signs (tense leg, pain out of proportion, pain on passive stretch) points more directly and urgently to compartment syndrome, which can occur even with palpable pulses. Compartment syndrome is a more common acute complication than complete popliteal artery occlusion in this scenario.
Question 2635
Topic: Pelvic & Acetabular Trauma
A 28-year-old female presents after a motorcycle accident with a mechanically unstable pelvic ring injury classified as a Young-Burgess Lateral Compression Type III. Her blood pressure is 90/60 mmHg, and heart rate is 120 bpm, despite initial fluid resuscitation. What is the most appropriate next step in her management?
Correct Answer & Explanation
. Application of a pelvic binder and continued resuscitation.
Explanation
A Young-Burgess Lateral Compression Type III (LC-III) pelvic ring injury indicates a significant pelvic disruption, typically involving a sacral fracture or sacroiliac joint disruption, leading to posterior instability and potential for severe retroperitoneal hemorrhage. In a hypotensive patient with a suspected pelvic hemorrhage, the immediate priority is to stabilize the pelvis and control bleeding. Application of a pelvic binder (or sheet) provides temporary external compression, reducing the pelvic volume and potentially tamponading venous bleeding, which accounts for the majority of hemorrhage in pelvic fractures. This should be combined with continued aggressive fluid resuscitation and transfusion.
Question 2636
Topic: 2. Trauma
A 62-year-old male falls from a ladder, sustaining a bimalleolar ankle fracture with medial comminution and lateral displacement. He has a history of poorly controlled diabetes and peripheral neuropathy. During surgery, excellent reduction and rigid internal fixation are achieved. Post-operatively, what is the most critical aspect of his immediate ankle rehabilitation protocol?
Correct Answer & Explanation
. Strict non-weight-bearing with vigilant skin and wound care.
Explanation
Correct Answer: CThis patient presents with several significant complicating factors: medial comminution (suggesting compromised medial soft tissues and potentially poor bone quality), poorly controlled diabetes, and peripheral neuropathy. Diabetes impairs wound healing, increases the risk of infection, and can lead to poor bone quality. Peripheral neuropathy further increases the risk of unrecognized skin breakdown, pressure sores, and Charcot arthropathy. Given these comorbidities and the complex nature of the fracture, strict non-weight-bearing is crucial to protect the surgical repair from excessive stress, which could lead to hardware failure, loss of reduction, or soft tissue complications. Vigilant skin and wound care are paramount due to his diabetic status and neuropathy, as even minor skin issues can rapidly escalate to severe infections.Why other options are incorrect:A. Early range of motion exercises to prevent stiffness:While important in some ankle fractures, early aggressive range of motion could jeopardize the fixation and healing in a patient with compromised soft tissues and bone quality.B. Aggressive weight-bearing as tolerated to promote bone healing:Aggressive weight-bearing is contraindicated due to the unstable nature of the fracture, the comminution, and the patient's comorbidities, which increase the risk of fixation failure and nonunion.D. Application of a functional brace with gradual weight-bearing progression:A functional brace and gradual weight-bearing would be premature and risky in the immediate post-operative period for this complex patient, as it could lead to loss of fixation and healing complications.E. Referral to physical therapy for immediate strengthening exercises:Immediate strengthening exercises are inappropriate and could compromise the surgical repair. Rehabilitation will be delayed and carefully progressed.
Question 2637
Topic: 2. Trauma
A 30-year-old female presents with a displaced femoral shaft fracture after a motor vehicle accident. She has significant chest trauma, requiring intubation and mechanical ventilation for pulmonary contusions. Her Injury Severity Score (ISS) is 25. What is the most appropriate timing for definitive fixation of her femoral fracture?
Correct Answer & Explanation
. After 3-7 days, once she is fully stabilized and out of the ICU (damage control orthopedics).
Explanation
Correct Answer: DThis patient is a polytrauma patient with significant chest injuries (pulmonary contusions requiring mechanical ventilation) and an Injury Severity Score (ISS) of 25. While early definitive fixation of long bone fractures is generally beneficial, patients with severe pulmonary compromise are at higher risk of adverse outcomes, such as Acute Respiratory Distress Syndrome (ARDS) or Fat Embolism Syndrome (FES), with immediate total care. In such cases, a 'damage control orthopedics' (DCO) approach is often preferred. This involves initial temporary stabilization of the femur, typically with an external fixator (as in option E, which is a component of DCO), followed by definitive intramedullary nailing once the patient's pulmonary status and overall physiological reserve have improved. This delay, typically after 3-7 days, allows for resolution of the 'second hit' inflammatory response and reduces the risk of systemic complications.Why other options are incorrect:A. Within 6 hours of admission (early total care):This is too aggressive for a patient with severe pulmonary contusions and high ISS, as it increases the risk of ARDS and FES.B. Within 24 hours of admission (early appropriate care):Similar to option A, this timeframe may still be too early for a patient with ongoing severe pulmonary compromise.C. Between 24-48 hours, after pulmonary stabilization:While better than immediate, this window might still be too soon if significant pulmonary compromise persists. The DCO principle suggests waiting until the patient is physiologically optimized, which often takes longer than 48 hours.E. Immediate external fixation, with delayed conversion to intramedullary nail:This describes themethodof damage control orthopedics, but option D describes thetimingof definitive fixation, which is the core of the question. The immediate external fixation is the initial temporary step, but the definitive fixation (conversion to IMN) is delayed until 3-7 days.
Question 2638
Topic: 2. Trauma
A 40-year-old male sustains a high-energy Pilon fracture (AO/OTA 43-C3) following a fall from significant height. Initial radiographs show severe comminution and articular involvement. The skin is intact but severely swollen with fracture blisters. What is the most appropriate initial management strategy for this fracture?
Correct Answer & Explanation
. Application of an external fixator with fibular fixation, followed by delayed ORIF.
Explanation
Correct Answer: BHigh-energy Pilon fractures (distal tibia articular fractures) are associated with severe soft tissue injury, often manifesting as significant swelling and fracture blisters. Immediate open reduction and internal fixation (ORIF) in the presence of such compromised soft tissues is contraindicated due to a very high risk of wound complications, infection, and skin necrosis. The most accepted initial management involves a 'staged' treatment approach: initial stabilization with an ankle-spanning external fixator, often combined with fibular fixation (if the fibula is unstable), to restore length, alignment, and indirectly reduce the fracture fragments. This allows the severe soft tissue swelling to subside (indicated by the 'wrinkle sign'), typically over 7-14 days, before definitive ORIF of the articular surface can be safely performed.Why other options are incorrect:A. Immediate open reduction and internal fixation (ORIF) to restore articular congruity:This is incorrect due to the high risk of wound complications in the presence of severe soft tissue swelling and fracture blisters.C. Skeletal traction through the calcaneus to distract the joint:While traction can help with length and alignment, it is usually incorporated into an external fixator setup rather than being the sole initial management. It does not provide the same stability or soft tissue protection as an external fixator.D. Strict non-weight-bearing cast application with close observation:A cast is insufficient for providing stable reduction and does not effectively manage severe soft tissue swelling in a high-energy Pilon fracture.E. Referral for immediate amputation due to severe injury:Amputation is a last resort for unsalvageable limbs (e.g., complete neurovascular disruption, severe crush with no viable tissue) and is not an initial consideration for an intact limb, even with severe fracture.
Question 2639
Topic: 2. Trauma
A 22-year-old collegiate athlete sustains a knee dislocation (tibiofemoral dislocation) during a football tackle. Initial assessment reveals a grossly deformed knee, but distal pulses are palpable and strong. After closed reduction in the emergency department, what is the most critical next step in management?
Correct Answer & Explanation
. Observed serial ankle-brachial index (ABI) measurements.
Explanation
Correct Answer: DKnee dislocations, even those that spontaneously reduce or are easily reduced in the ED and have palpable pulses, carry a high risk of popliteal artery injury (up to 40% in some series). The popliteal artery can be stretched, compressed, or intimaly damaged during the dislocation, leading to delayed thrombosis, pseudoaneurysm formation, or compartment syndrome. Therefore, close monitoring for vascular compromise is paramount. While a CT angiography (CTA) is a definitive diagnostic tool for vascular injury, observed serial ankle-brachial index (ABI) measurements (e.g., every hour for 24-48 hours) combined with clinical examination is the standard screening tool. An ABI < 0.9 or a significant drop in ABI warrants immediate further investigation (e.g., CTA).Why other options are incorrect:A. Application of a hinged knee brace and immediate physical therapy:Early bracing and physical therapy would be inappropriate without first clearing the vascular status, as an unrecognized vascular injury could lead to catastrophic limb loss.B. Urgent MRI of the knee to evaluate ligamentous injuries:MRI is essential for evaluating the extent of ligamentous injuries (which are almost always multiple in knee dislocations) but is not the immediate priority. Vascular integrity must be confirmed first.C. Immediate CT angiography of the affected limb:While CTA is the definitive diagnostic test for vascular injury, it is not always theimmediatenext step if pulses are initially strong and ABIs are normal. Serial ABIs are a cost-effective and sensitive screening tool. CTA is indicated if ABIs are abnormal or if there is high clinical suspicion despite normal ABIs.E. Admission for neurovascular observation and serial examinations:This is a correct general approach, but option D is more precise and highlights the specific critical tool (serial ABI measurements) used during that observation period to detect subtle or delayed vascular compromise.
Question 2640
Topic: Lower Extremity Trauma
A 40-year-old male sustains an open Schatzker III tibial plateau fracture. During initial debridement, he is noted to have significant devitalized muscle and a large skin defect that cannot be closed primarily. What is the most appropriate definitive soft tissue management for this injury?
Correct Answer & Explanation
. Free tissue transfer (microvascular flap).
Explanation
An open Schatzker III tibial plateau fracture with significant devitalized muscle and a large skin defect that cannot be closed primarily requires robust soft tissue coverage, especially when bone, hardware, or vital structures are exposed. In cases of large defects or significant muscle loss, free tissue transfer (microvascular flap) is often the most appropriate definitive soft tissue management. Free flaps provide a large volume of vascularized tissue, excellent padding, and can cover complex defects, offering the best chance for wound healing and infection prevention.
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