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 1681
Topic: 2. Trauma
A 32-year-old female sustains a Pronation-External Rotation (PER) ankle fracture. According to Lauge-Hansen, what is the final (Stage IV) injury in this specific mechanistic pattern?
Correct Answer & Explanation
. Medial malleolus fracture or deltoid ligament tear
Explanation
The PER sequence proceeds as follows: 1) Medial injury (deltoid/malleolus), 2) AITFL rupture, 3) High fibular fracture, and 4) PITFL rupture or posterior malleolus fracture.
Question 1682
Topic: 2. Trauma
During fasciotomies for foot compartment syndrome, the surgeon must decompress the central compartment. Which of the following muscles is located within this compartment?
Correct Answer & Explanation
. Flexor digitorum brevis
Explanation
The central compartment of the foot contains the flexor digitorum brevis, quadratus plantae, lumbricals, and the flexor hallucis longus tendon. The abductor hallucis is in the medial compartment.
Question 1683
Topic: 2. Trauma
A 40-year-old man falls from a height, sustaining a severely comminuted calcaneus fracture. Over the next 12 hours, his foot becomes massively swollen. Which clinical finding is the earliest and most reliable indicator of foot compartment syndrome?
Correct Answer & Explanation
. Severe pain with passive dorsiflexion of the toes
Explanation
Pain out of proportion to the injury and severe pain with passive stretch of the involved muscles (e.g., passive toe dorsiflexion stretching the intrinsic flexors) are the earliest and most reliable signs of compartment syndrome.
Question 1684
Topic: 2. Trauma
During open reduction and internal fixation of a bimalleolar equivalent ankle fracture, the lateral malleolus is plated. A 'Cotton test' is then performed using a bone hook on the fibula, which demonstrates a 5 mm widening of the medial clear space. What is the most appropriate next step?
Correct Answer & Explanation
. Place a syndesmotic stabilization device (screw or suture button)
Explanation
A positive Cotton test indicates syndesmotic instability after lateral (and medial) fixation. A syndesmotic screw or flexible fixation device is required to stabilize the distal tibiofibular joint.
Question 1685
Topic: 2. Trauma
How many distinct fascial compartments are anatomically recognized in the foot for the purpose of fasciotomy?
Correct Answer & Explanation
. Nine
Explanation
There are nine distinct compartments in the foot: medial, lateral, superficial, calcaneal, adductor, and four interosseous compartments. Thorough decompression of all nine is required in cases of foot compartment syndrome.
Question 1686
Topic: 2. Trauma
What is the most reliable objective threshold for diagnosing foot compartment syndrome and indicating the need for emergent fasciotomy?
Correct Answer & Explanation
. Delta P (diastolic blood pressure minus compartment pressure) of less than 30 mmHg
Explanation
A Delta P (diastolic pressure minus compartment pressure) of less than 30 mmHg is the most reliable threshold for diagnosing compartment syndrome. Loss of pulses is a late and unreliable sign of compartment syndrome.
Question 1687
Topic: 2. Trauma
When evaluating a patient for suspected foot compartment syndrome, which compartment is considered the most clinically crucial to measure as it is the largest and frequently exhibits the highest pressures?
Correct Answer & Explanation
. Central compartment
Explanation
The central compartment is the largest of the foot compartments and most commonly records the highest pressures in foot compartment syndrome. It contains the flexor digitorum brevis, lumbricals, and adductor hallucis.
Question 1688
Topic: 2. Trauma
During surgical fixation of a trimalleolar ankle fracture, anatomical reduction and internal fixation of the posterior malleolus (Volkmann's fragment) primarily restores syndesmotic stability by reconstructing which structure?
The posterior inferior tibiofibular ligament (PITFL) attaches to the posterior malleolus. Anatomic fixation of a posterior malleolar fracture restores the tension and function of the PITFL, providing significant syndesmotic stability.
Question 1689
Topic: 2. Trauma
During a twisting ankle injury, an avulsion fracture of the anterior inferior tibiofibular ligament (AITFL) from the distal tibia is observed. What is the anatomical eponym for this specific fracture fragment?
Correct Answer & Explanation
. Tillaux-Chaput fragment
Explanation
The Tillaux-Chaput fragment is an avulsion of the AITFL from the anterolateral distal tibia. The Wagstaffe fragment is an AITFL avulsion from the anterior fibula, and the Volkmann fragment involves the posterior tibia (PITFL).
Question 1690
Topic: 2. Trauma
A patient undergoes an open fasciotomy for foot compartment syndrome via the standard double dorsal incision approach. Which neurovascular structure is at greatest iatrogenic risk during the placement of the medial dorsal incision?
Correct Answer & Explanation
. Deep peroneal nerve and dorsalis pedis artery
Explanation
The medial dorsal incision is typically placed slightly medial to the second metatarsal shaft. This places the deep peroneal nerve and dorsalis pedis artery, which course in the first intermetatarsal space, at significant risk.
Question 1691
Topic: 2. Trauma
A 30-year-old male presents with isolated medial ankle pain after a severe twisting injury. Radiographs reveal an isolated transverse medial malleolus fracture with widening of the medial clear space, but no fibular fracture at the ankle. What is the most critical next step in clinical evaluation?
Correct Answer & Explanation
. Palpate and radiograph the entire length of the tibia and fibula
Explanation
An isolated medial malleolus fracture with medial clear space widening suggests a syndesmotic injury. The examiner must evaluate the entire fibula to rule out a Maisonneuve fracture (proximal fibula fracture).
Question 1692
Topic: 2. Trauma
The calcaneal compartment of the foot communicates proximally with which anatomical compartment, allowing for the potential proximal spread of infection or compartment syndrome?
Correct Answer & Explanation
. Deep posterior compartment of the leg
Explanation
The calcaneal compartment communicates intimately with the deep posterior compartment of the leg along the neurovascular bundle, serving as a conduit for fluid, blood, or infection.
Question 1693
Topic: Lower Extremity Trauma
When evaluating standard AP and mortise radiographs of the ankle to rule out syndesmotic injury, the tibiofibular clear space (measured 1 cm above the joint line) is considered abnormal if it exceeds what measurement?
Correct Answer & Explanation
. 6 mm
Explanation
A tibiofibular clear space greater than 5-6 mm on either the AP or mortise view is widely accepted as abnormal and indicative of a syndesmotic widening.
Question 1694
Topic: 2. Trauma
According to the Lauge-Hansen classification, what is the correct sequential order of structural failure in a Supination-External Rotation (SER) ankle injury?
The SER mechanism progresses in four stages: 1) Anterior inferior tibiofibular ligament (AITFL) rupture, 2) Spiral/oblique fracture of the lateral malleolus, 3) Posterior inferior tibiofibular ligament (PITFL) rupture or posterior malleolus fracture, and 4) Deltoid rupture or medial malleolus fracture.
Question 1695
Topic: 2. Trauma
A 45-year-old female presents with a trimalleolar ankle fracture.
According to recent biomechanical and clinical literature, what is the primary rationale for open reduction and internal fixation of the posterior malleolus?
Correct Answer & Explanation
. To restore the incisura fibularis and reestablish syndesmotic stability via the PITFL
Explanation
Recent guidelines emphasize fixing the posterior malleolus to restore the incisura fibularis and the posterior inferior tibiofibular ligament (PITFL) attachment. This optimally restores syndesmotic stability and joint congruity, shifting focus away from strict fragment size percentage thresholds.
Question 1696
Topic: 2. Trauma
A 24-hour-old macrosomic newborn presents with right upper extremity flaccidity and an absent Moro reflex on the affected side, similar to the case described. Initial radiographs of the right shoulder and humerus are normal. Which of the following findings would most strongly suggest a diagnosis of clavicle fracture over brachial plexus birth palsy?
Correct Answer & Explanation
. Focal tenderness and crepitus over the mid-clavicle.
Explanation
Correct Answer: CThe case explicitly states that gentle palpation of the right clavicle, humerus, and shoulder joint revealed no tenderness, crepitus, or focal swelling, effectively ruling out a gross clavicular or humeral fracture. A clavicle fracture is the most common birth injury and often presents with pseudoparalysis (the infant holds the arm still due to pain), focal tenderness, crepitus, or swelling over the clavicle. While the Moro reflex might be guarded due to pain, it is often present. In contrast, brachial plexus birth palsy presents with true paralysis and specific neurological deficits without bony tenderness or crepitus. The other options (intact grasp reflex, 'waiter's tip' posture, absent biceps reflex, normal passive ROM) are all consistent with or characteristic of brachial plexus birth palsy, not a clavicle fracture.
Question 1697
Topic: 2. Trauma
To minimize donor site morbidity and optimize the take of a full-thickness skin graft following harvest of a radial forearm flap, which of the following technical steps is most critical?
Correct Answer & Explanation
. Maintaining the paratenon over the flexor carpi radialis and brachioradialis tendons.
Explanation
Successful skin grafting of the donor site requires a well-vascularized bed. Meticulous dissection to preserve the paratenon over the exposed brachioradialis and flexor carpi radialis tendons is critical to prevent graft failure and subsequent tendon desiccation.
Question 1698
Topic: 2. Trauma
To further mitigate the risk of a pathologic fracture of the radius following an osteocutaneous reverse radial forearm flap harvest, what specific technical modification should be applied to the osteotomy design?
Correct Answer & Explanation
. Creating a boat-shaped (keel) osteotomy with beveled edges
Explanation
A boat-shaped or keeled osteotomy with beveled ends prevents stress risers at the corners of the harvest site. This technique significantly reduces the risk of postoperative radius fractures.
Question 1699
Topic: 2. Trauma
A 48-year-old male with a comminuted femur fracture presents with signs of hypovolemic shock. After initial fluid resuscitation with 2 liters of crystalloid, his blood pressure remains 90/50 mmHg, and heart rate is 120 bpm. His hemoglobin is 8.0 g/dL. What is the next most appropriate step in management?
Correct Answer & Explanation
. Transfuse 2 units of packed red blood cells (PRBCs)
Explanation
Correct Answer: CIn a trauma patient with ongoing signs of hypovolemic shock despite initial crystalloid resuscitation, and with a hemoglobin of 8.0 g/dL, hemorrhage is the most likely cause. Transfusion of packed red blood cells is indicated to improve oxygen-carrying capacity and intravascular volume. Current trauma guidelines (ATLS) recommend blood product administration early in hemorrhagic shock. Continuing with crystalloids alone is often insufficient and can lead to dilutional coagulopathy and worsening shock. Vasopressors are generally not the first-line treatment for hemorrhagic shock, as they can mask ongoing blood loss and worsen tissue perfusion; they are considered if profound shock persists despite adequate volume resuscitation. DPL is less common now with FAST exam availability, and the focus should be on resuscitation and hemorrhage control. CVP monitoring is a supportive measure but not the immediate intervention to address ongoing shock.
Question 1700
Topic: 2. Trauma
A 70-year-old male with a history of heart failure and chronic kidney disease (CKD) Stage III undergoes open reduction and internal fixation of a distal femur fracture. On post-operative day 2, his serum sodium is 128 mEq/L, and he has crackles in his lungs with peripheral edema. His blood pressure is 140/85 mmHg. Urine output is 30 mL/hr. What is the most appropriate initial management for his hyponatremia?
Correct Answer & Explanation
. Institute fluid restriction to 1 L/day
Explanation
This patient presents with hypervolemic hyponatremia, evidenced by crackles (pulmonary edema) and peripheral edema, and a history of conditions (heart failure, CKD) that predispose to fluid overload. The most appropriate initial management is fluid restriction. Administering 3% hypertonic saline is reserved for severe, symptomatic hyponatremia (typically Na+ <120 mEq/L or acute neurological symptoms) or for patients who are not hypervolemic. Administering more 0.9% Normal Saline would worsen his fluid overload. Oral sodium tablets would add solute, but the primary issue is excess free water, not sodium deficiency.
Test Yourself
Switch to an interactive, timed exam simulation to truly master this topic.
