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 1381
Topic: 2. Trauma
A 65-year-old female falls onto her outstretched hand and sustains the injury depicted below.
Based on modern anatomic perfusion studies, which vessel provides the predominant blood supply to the humeral head that is at risk in complex proximal humerus fractures?
Correct Answer & Explanation
. Posterior humeral circumflex artery
Explanation
While the anterior humeral circumflex artery provides the arcuate branch, recent quantitative studies demonstrate that the posterior humeral circumflex artery provides the predominant blood supply (up to 64%) to the humeral head and is critical in proximal humerus fractures.
Question 1382
Topic: Upper Extremity Trauma
A 25-year-old mountain biker falls directly onto the point of his shoulder. Radiographs demonstrate a 150% superior displacement of the distal clavicle relative to the acromion with an increased coracoclavicular distance. Which classification and typical management strategy correspond to this injury?
Correct Answer & Explanation
. Type V, operative reconstruction
Explanation
A Type V acromioclavicular (AC) joint injury is characterized by 100-300% superior displacement of the clavicle due to disruption of the CC ligaments and deltotrapezial fascia. Operative reconstruction is generally recommended for young, active patients to restore normal shoulder mechanics.
Question 1383
Topic: 2. Trauma
A 35-year-old male cyclist sustains a completely displaced midshaft clavicle fracture. Which of the following initial radiographic or clinical characteristics is most highly predictive of nonunion if this fracture is treated non-operatively?
Correct Answer & Explanation
. Initial fracture shortening > 2 cm
Explanation
Fracture shortening greater than 2 cm (or 100% displacement) in midshaft clavicle fractures is a significant biomechanical risk factor for nonunion. It is widely considered a relative indication for surgical fixation.
Question 1384
Topic: 2. Trauma
A 68-year-old female sustains a 4-part proximal humerus fracture. According to the Hertel criteria, which of the following radiographic findings is the strongest predictor of humeral head ischemia?
Correct Answer & Explanation
. Metaphyseal head extension (calcar length) less than 8 mm
Explanation
The Hertel criteria identify a metaphyseal head extension (calcar length) of <8 mm and a disrupted medial hinge (>2 mm) as the most reliable predictors of humeral head ischemia. These findings suggest profound disruption of the ascending branch of the anterior humeral circumflex artery and intraosseous collateral blood supply.
Question 1385
Topic: Upper Extremity Trauma
A 25-year-old cyclist falls directly onto his right shoulder. Clinical examination reveals profound superior prominence of the distal clavicle. Radiographs demonstrate the distal clavicle displaced superiorly by 150% relative to the acromion. Which of the following describes the injured structures in a Type V acromioclavicular (AC) joint separation?
Correct Answer & Explanation
. Tear of the AC and CC ligaments with stripping of the deltotrapezial fascia
Explanation
A Type V AC joint separation involves severe superior displacement (>100-300%) due to disruption of both the AC and CC ligaments, along with extensive stripping or tearing of the deltotrapezial fascia. This degree of instability generally warrants surgical reconstruction.
Question 1386
Topic: 2. Trauma
A 19-year-old male involved in a high-speed motor vehicle collision presents to the trauma bay with severe chest pain, stridor, and dysphagia. Examination shows a palpable depression at the right medial clavicle. Standard AP chest radiographs are inconclusive. What is the most appropriate next step in management?
Correct Answer & Explanation
. CT scan of the chest with intravenous contrast
Explanation
This clinical presentation is highly suspicious for a posterior sternoclavicular dislocation, which can compromise the trachea, esophagus, or great vessels. A CT scan of the chest with IV contrast is the gold standard to evaluate the displacement and integrity of the mediastinal structures prior to any reduction attempts.
Question 1387
Topic: 2. Trauma
During open reduction and internal fixation of a displaced lateral malleolus fracture, a surgeon encounters a blocked reduction. Upon inspection, the Extensor Digitorum Brevis (EDB) muscle belly is identified as the interposing structure, as depicted conceptually in the intraoperative field.
What is the most appropriate and least damaging method to manage this EDB interposition to achieve anatomical reduction?
Correct Answer & Explanation
. Gently retract the EDB muscle belly or tendon, usually anteriorly or superiorly, using a small blunt retractor.
Explanation
Correct Answer: CThe case explicitly states under 'Management of EDB Interposition' that the correct approach is to 'Gently retract the EDB muscle belly or tendon, usually anteriorly or superiorly, using a small blunt retractor (e.g., Hohmann retractor, Senn retractor, or even a dental pick). Avoid excessive force to prevent muscle damage. Once the EDB is cleared from the fracture site, anatomical reduction should become readily achievable.'Option A is incorrect because resection of the EDB is unnecessary and would cause permanent damage to the muscle. Option B is incorrect as incising the tendon is an overly aggressive and potentially damaging approach when simple retraction is effective. Option D is incorrect; applying a bone clamp directly to soft tissue like the EDB would cause significant trauma and is not an appropriate surgical technique. Option E is incorrect; a fasciotomy of the anterior compartment is indicated for compartment syndrome, not for clearing an interposing EDB muscle belly from a fracture site.
Question 1388
Topic: 2. Trauma
A 60-year-old diabetic patient presents with a complex trimalleolar ankle fracture-dislocation. Initial radiographs show significant comminution and displacement. The surgical team is concerned about potential intra-articular fragments and the precise morphology of the posterior malleolus. Which of the following imaging modalities is most strongly recommended for pre-operative planning in this specific scenario, especially when anticipating potential challenges like blocked reduction?
Correct Answer & Explanation
. Computed Tomography (CT) scan of the ankle.
Explanation
Correct Answer: CThe case states under 'Pre-Operative Assessment and Imaging' that 'Computed Tomography (CT) Scan is strongly recommended for complex fracture patterns (e.g., trimalleolar, pilon fractures) to delineate articular involvement, fracture comminution, and the presence of osteochondral fragments. It is highly valuable in identifying potential soft tissue interposition pre-operatively, though EDB interposition might not always be clearly evident. It provides a 3D understanding of the deformity and helps plan implant placement.'Option A, stress radiographs, are primarily used to assess syndesmotic stability, not for detailed fracture morphology or comminution. Option B, MRI, is excellent for soft tissue assessment but is generally not the first-line imaging for acute fracture morphology and is less efficient for bony detail than CT. Option D, contralateral ankle views, are useful for comparison but do not provide the detailed 3D information needed for complex fractures. Option E, bone scintigraphy, is used for metabolic bone activity or occult fractures, not for acute pre-operative planning of complex ankle fractures.
Question 1389
Topic: 2. Trauma
A surgeon is performing an open reduction and internal fixation of a lateral malleolus fracture using a standard longitudinal incision centered over the distal fibula. The image below conceptually illustrates the anatomical region.
During dissection of the skin and subcutaneous tissue, which neurovascular structure is most critical to identify and protect to prevent sensory deficits or painful neuromas?
Correct Answer & Explanation
. Superficial peroneal nerve.
Explanation
Correct Answer: EThe case explicitly states under 'Lateral Malleolus Fracture and EDB Interposition' in the 'Dissection' section: 'Carefully incise the skin and subcutaneous tissue. Identify and protect thesuperficial peroneal nerve (SPN)and its branches, which cross the ankle anteriorly. Aggressive retraction or direct injury to the SPN can lead to sensory deficits or painful neuromas.'Option A, the posterior tibial nerve, is located in the deep posterior compartment and is not typically at risk during a standard lateral approach. Option B, the saphenous nerve, is located medially and is at risk during a medial malleolus approach. Option C, the sural nerve, is located posterolaterally but is generally posterior to the standard lateral malleolus incision. Option D, the deep peroneal nerve, is in the anterior compartment but is typically deeper and more medial than the superficial peroneal nerve branches that are immediately subcutaneous in the vicinity of a lateral malleolus incision.
Question 1390
Topic: 2. Trauma
Which of the following is the most significant risk factor for the development of infantile Blount disease?
Correct Answer & Explanation
. Early walking and obesity
Explanation
Infantile Blount disease is strongly associated with early walking and childhood obesity. These factors place excessive compressive forces on the medial proximal tibial physis, leading to growth disturbance.
Question 1391
Topic: 2. Trauma
A 5-year-old boy with severe infantile Blount disease (Langenskiöld stage IV) undergoes a proximal tibial corrective osteotomy. Postoperatively, he develops weakness in ankle dorsiflexion and numbness over the first dorsal web space. Which structure was most likely injured?
Correct Answer & Explanation
. Deep peroneal nerve
Explanation
Weakness in ankle dorsiflexion (tibialis anterior) and numbness in the first dorsal web space indicate a deep peroneal nerve injury. The common peroneal nerve and its branches are at risk during proximal tibial osteotomies, either from direct injury or compartment syndrome.
Question 1392
Topic: 2. Trauma
A 40-year-old construction worker falls from a height and sustains a severely comminuted tibial plafond (pilon) fracture with significant soft tissue swelling and fracture blisters. What is the most appropriate initial management strategy?
Correct Answer & Explanation
. Application of an external fixator, followed by delayed definitive ORIF
Explanation
High-energy pilon fractures are associated with severe soft tissue compromise. The standard of care is a staged approach: immediate application of a spanning external fixator, followed by definitive ORIF once the soft tissue envelope has healed.
Question 1393
Topic: Upper Extremity Trauma
A 28-year-old male rugby player sustains a direct blow to the superior aspect of his right shoulder with his arm adducted during a tackle. He presents with significant pain and a visible deformity. Radiographs show superior displacement of the distal clavicle, with the coracoclavicular distance measured at 20 mm on the injured side compared to 10 mm on the contralateral uninjured side. The deltotrapezial fascia appears intact. Which Rockwood classification best describes this injury?
Correct Answer & Explanation
. Type III
Explanation
The case describes a Rockwood Type III injury. According to the Rockwood classification system, a Type III injury involves complete tears of both the acromioclavicular and coracoclavicular ligaments. The clavicle is significantly displaced superiorly, typically demonstrating a 25 to 100 percent increased coracoclavicular distance. In this patient, the coracoclavicular distance increased from 10 mm to 20 mm, representing a 100% increase, which falls within the Type III criteria. Furthermore, the deltotrapezial fascia remaining intact is a key distinguishing feature of Type III compared to Type V, where it is extensively stripped. Type II involves a complete tear of the acromioclavicular ligaments with intact coracoclavicular ligaments and less than 25% increase in coracoclavicular distance. Type IV involves posterior displacement of the clavicle into the trapezius, requiring an axillary lateral radiograph for diagnosis, which is not indicated here. Type V involves severe superior displacement exceeding 100% of the normal coracoclavicular distance and extensive stripping of the deltoid and trapezius fascia, which is not described as stripped in this case.
Question 1394
Topic: Upper Extremity Trauma
A surgeon is performing an open reduction and internal fixation of a chronic acromioclavicular joint separation. During the procedure, they note significant horizontal instability of the clavicle on the acromion, even after initial reduction. Based on the provided case, which ligamentous structure is the primary restraint to this specific type of instability?
Correct Answer & Explanation
. Superior acromioclavicular ligament
Explanation
Correct Answer: CThe case explicitly states under the 'Static Stabilizers' section: 'Biomechanically, the acromioclavicular ligaments provide the primary restraint to anterior-posterior horizontal translation of the clavicle on the acromion. Sectioning the superior acromioclavicular ligament results in profound horizontal instability.' The conoid and trapezoid ligaments (coracoclavicular ligaments) are crucial for vertical stability. The coracoacromial ligament is not a primary stabilizer of the AC joint itself, and the articular disc's role in stability is minimal, especially given its degeneration with age.
Question 1395
Topic: Upper Extremity Trauma
A 35-year-old construction worker presents with a Rockwood Type III acromioclavicular joint injury after a fall from scaffolding. He reports significant pain and difficulty performing overhead tasks required for his job. On physical exam, he has dynamic overriding of the clavicle on the acromion during cross-body adduction. Based on the ISAKOS guidelines mentioned in the case, what is the most appropriate management strategy?
Correct Answer & Explanation
. Surgical stabilization with an acute suspensory cortical button fixation.
Explanation
Correct Answer: B. The case highlights the ISAKOS Upper Extremity Committee's subclassification of Type III injuries into Type IIIA (vertically unstable but horizontally stable) and Type IIIB (vertically and horizontally unstable). The consensus suggests that Type IIIA injuries are best managed non-operatively, while Type IIIB injuries, characterized by dynamic overriding of the clavicle on the acromion during cross-body adduction, often experience poor functional outcomes with conservative care and may benefit from early surgical stabilization. This patient is a manual laborer and presents with dynamic overriding during cross-body adduction, which is characteristic of a Type IIIB injury. Since the injury is acute, acute suspensory cortical button fixation is the appropriate surgical technique. Chronic biologic reconstruction is for injuries presenting after six weeks. Distal clavicle excision is typically for chronic osteolysis or arthrosis, not acute instability.
Question 1396
Topic: 2. Trauma
A 22-year-old collegiate football player undergoes arthroscopically assisted suspensory cortical button fixation for an acute Rockwood Type V acromioclavicular joint separation. During the procedure, the surgeon is preparing to drill the coracoid tunnel. Based on the case, what is a critical technical consideration to minimize the risk of iatrogenic coracoid fracture?
Correct Answer & Explanation
. Placing the guide pin centrally at the base of the coracoid.
Explanation
Correct Answer: CUnder the 'Acute Injury Management' section, the case states: 'Coracoid Preparation: The base of the coracoid is exposed. Using fluoroscopic guidance or arthroscopic visualization, a guide pin is placed centrally at the base of the coracoid. It is critical to place this pin centrally to avoid eccentric drilling, which drastically increases the risk of iatrogenic coracoid fracture.' Eccentric drilling, multiple drill holes, or drill holes exceeding 4mm in diameter are all identified as etiologies for coracoid fracture in the 'Complications' table. Avoiding fluoroscopy would increase the risk of malposition, and drilling before exposure would be unsafe.
Question 1397
Topic: Upper Extremity Trauma
The ISAKOS Upper Extremity Committee has provided consensus guidelines for the management of Rockwood Type III acromioclavicular joint injuries. According to these guidelines, which of the following patient presentations would most likely benefit from early surgical stabilization?
Correct Answer & Explanation
. A 40-year-old manual laborer with a Type IIIB injury, demonstrating dynamic overriding of the clavicle on the acromion during cross-body adduction.
Explanation
Correct Answer: C. The ISAKOS consensus guidelines subclassified Type III injuries into Type IIIA (vertically unstable but horizontally stable) and Type IIIB (vertically and horizontally unstable). The current consensus suggests that Type IIIA injuries are best managed non-operatively, while Type IIIB injuries, characterized by dynamic overriding of the clavicle on the acromion during cross-body adduction, often experience poor functional outcomes with conservative care and may benefit from early surgical stabilization. Option C describes a manual laborer with a Type IIIB injury, which is the specific indication for early surgical stabilization.
Question 1398
Topic: 2. Trauma
A 42-year-old patient undergoes ORIF for a greater tuberosity fracture. Intraoperatively, the surgeon uses the technique shown in the image below to achieve stable fixation of a large, single fragment.
Which of the following principles is best demonstrated by the fixation method depicted, and what is its primary advantage for this type of fracture?
Correct Answer & Explanation
. Lag screw fixation; provides interfragmentary compression for rigid stability.
Explanation
Correct Answer: BThe image depicts screws crossing the fracture line, which is characteristic of lag screw fixation. The case describes lag screw fixation as a technique where screws are placed across the fracture site in a lag fashion to achieve interfragmentary compression. This provides rigid fixation and excellent compression, which is advantageous for larger, single, well-corticated fragments. Tension band wiring typically involves wires, not screws. Neutralization plating uses a plate to protect screws from bending forces, which is not the primary principle shown. Suture anchor repair uses anchors and sutures, not screws, to reattach the rotator cuff footprint. Intramedullary nailing involves a rod placed within the medullary canal, which is not shown.
Question 1399
Topic: 2. Trauma
During an orthopedic grand rounds, a debate arises regarding the optimal fixation method for a displaced greater tuberosity fracture in a 50-year-old patient with good bone quality. One surgeon advocates for suture anchors, another for lag screws, and a third for a small plate. Based on the provided case material, which statement best reflects the current consensus and controversies regarding fixation methods for greater tuberosity fractures?
Correct Answer & Explanation
. There is no single universally accepted 'best' fixation method, with choice depending on fragment characteristics, bone quality, and surgeon preference.
Explanation
Correct Answer: DThe 'Summary of Key Literature / Guidelines' section explicitly states, 'There is no single universally accepted 'best' fixation method.' It further elaborates that the decision often comes down to surgeon preference, fragment characteristics, and bone quality. Suture fixation is often preferred for smaller avulsion fragments or osteoporotic bone, but also for broad reattachment of the rotator cuff footprint. Screw fixation is suitable for larger, sturdy fragments. Plate fixation is less common for isolated GT fractures. Therefore, options A, B, and C represent oversimplifications or incorrect statements regarding the indications or contraindications of specific methods. Option E is also incorrect, as the role of arthroscopy is still an evolving concept, and it has not been definitively proven superior in all cases, nor is it suitable for all fracture types.
Question 1400
Topic: 2. Trauma
A 35-year-old male presents to the emergency department after a fall onto an outstretched arm, sustaining the injury shown in the radiograph below. He reports numbness in the dorsal first web space and inability to extend his wrist and fingers.
Correct Answer & Explanation
. C. A spiral or oblique fracture of the distal one-third of the humerus, uniquely predisposing the radial nerve to entrapment.
Explanation
Correct Answer: CThe radiograph depicts a spiral or oblique fracture of the distal one-third of the humerus, consistent with a Holstein–Lewis fracture. The clinical presentation of numbness in the dorsal first web space and inability to extend the wrist and fingers is characteristic of a radial nerve palsy. The case description explicitly states that the Holstein–Lewis fracture is a specific spiral or oblique fracture of the distal one-third of the humerus, characterized by its high association with radial nerve injury (10-20% incidence). The sharp, displaced proximal fracture fragment uniquely predisposes the radial nerve to entrapment or direct laceration.Option A is incorrect because Holstein–Lewis fractures are typically spiral or oblique, not transverse, and have a significantly high risk of radial nerve injury. Option B is incorrect as Holstein–Lewis fractures are associated with radial nerve injury, not typically median nerve injury, and are not primarily supracondylar in the classic sense of pediatric supracondylar fractures. Option D is incorrect as Holstein–Lewis fractures typically spare the articular surface. Option E is incorrect as the fracture is in the distal humerus, not the proximal humerus, and is not managed with shoulder arthroplasty.
Test Yourself
Switch to an interactive, timed exam simulation to truly master this topic.
