Menu

2. Trauma MCQs

Practice Set 232 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 4621

Topic: 2. Trauma

A 65-year-old female sustains a comminuted, intra-articular distal humerus fracture (AO/OTA type 13-C3).

During open reduction and internal fixation using dual plating, what is the consensus regarding the biomechanical stability of parallel versus orthogonal plating constructs?

. Orthogonal plating is vastly superior to parallel plating
. Parallel plating is vastly superior to orthogonal plating
. Properly applied orthogonal and parallel plating provide equivalent functional outcomes and comparable stability
. Single column plating is preferred for type 13-C3 fractures
. Intramedullary nailing provides the best stability for intra-articular extension

Correct Answer & Explanation

. Orthogonal plating is vastly superior to parallel plating

Explanation

For bicolumnar distal humerus fractures, both parallel (plates on the medial and lateral ridges) and orthogonal (one medial, one posterolateral) plating techniques are acceptable. Biomechanical studies and randomized controlled trials have shown that properly applied parallel and orthogonal constructs provide equivalent clinical outcomes and comparable biomechanical stability, provided the principles of stable fixation (maximizing screws in the distal fragments) are met.

Question 4622

Topic: 2. Trauma
A 35-year-old male falls onto an outstretched hand. Radiographs reveal a comminuted radial head fracture with 4 distinct articular fragments, none of which are attached to the radial neck (Mason Type III). There is no clinical or radiographic evidence of elbow instability or interosseous membrane injury. What is the most appropriate surgical treatment?
. Nonoperative management with early range of motion
. Radial head excision without replacement
. Open reduction and internal fixation with mini-fragment plates
. Radial head arthroplasty
. Ligamentous repair only

Correct Answer & Explanation

. Radial head arthroplasty

Explanation

For Mason Type III (comminuted) radial head fractures with > 3 fragments that are entirely displaced from the radial neck, open reduction and internal fixation (ORIF) has a high failure rate and risk of nonunion or avascular necrosis. Radial head arthroplasty is the treatment of choice. Excision alone is no longer favored due to the risk of proximal radial migration.

Question 4623

Topic: 2. Trauma

A 30-year-old male sustains a closed fracture of the distal third of the humerus. On examination, he has weak wrist extension and numbness in the first dorsal web space. Which of the following describes the most common mechanism of radial nerve injury in this specific fracture pattern?

. Stretching of the nerve over the proximal fragment
. Entrapment of the nerve in the lateral intermuscular septum
. Laceration of the nerve by the distal fragment
. Entrapment of the nerve between the fracture fragments
. Traction injury at the axilla

Correct Answer & Explanation

. Stretching of the nerve over the proximal fragment

Explanation

A spiral fracture of the distal third of the humeral shaft (Holstein-Lewis fracture) has a high association with radial nerve palsy (up to 22%). As the nerve pierces the lateral intermuscular septum, it is relatively tethered. The most common mechanism of nerve injury in this pattern is direct contusion or entrapment between the fracture fragments, especially during injury or attempted closed reduction.

Question 4624

Topic: 2. Trauma

A 28-year-old cyclist falls onto his right shoulder. Radiographs demonstrate a completely displaced, shortened midshaft clavicle fracture. Which of the following represents an absolute indication for open reduction and internal fixation of this acute clavicle fracture?

. 15 mm of shortening
. Complete displacement with no cortical contact
. Open fracture
. Z-deformity with a vertical intermediate fragment
. Associated non-displaced scapular spine fracture

Correct Answer & Explanation

. 15 mm of shortening

Explanation

Absolute indications for operative treatment of an acute clavicle fracture include: open fracture, associated neurovascular injury, skin tenting with impending breakdown, and severe polytrauma. Shortening >2 cm, complete displacement, and Z-deformity are relative indications based on increased risk of nonunion and symptomatic malunion, but they are not absolute indications.

Question 4625

Topic: 2. Trauma

A 55-year-old smoker presents with persistent arm pain and mobility 9 months after sustaining a midshaft humerus fracture treated nonoperatively. Radiographs confirm an atrophic nonunion. What is the most appropriate surgical management?

. Functional bracing for an additional 3 months and use of a bone stimulator
. Intramedullary nailing with locked screws
. Open reduction, internal fixation with dynamic compression plating, and autologous bone grafting
. External fixation with a circular frame
. Surgical exploration and radial nerve release only

Correct Answer & Explanation

. Open reduction, internal fixation with dynamic compression plating, and autologous bone grafting

Explanation

The treatment of choice for an atrophic humerus shaft nonunion is rigid stabilization and biologic stimulation. Open reduction and internal fixation (ORIF) with plate and screws provides superior compression and stability compared to intramedullary nailing for nonunions. Autologous bone grafting (e.g., iliac crest bone graft) is necessary because it is an atrophic nonunion, providing osteogenic, osteoinductive, and osteoconductive properties.

Question 4626

Topic: 2. Trauma

A 22-year-old motorcyclist is brought to the trauma bay after a high-speed collision. He has massive swelling over his left shoulder and is pulseless in the left upper extremity. Radiographs reveal a completely displaced clavicle fracture, multiple rib fractures, and marked lateral displacement of the scapula relative to the spine. What is the most appropriate initial diagnostic or therapeutic step regarding the vascular injury?

. Immediate above-elbow amputation
. CT angiography of the left upper extremity
. Closed reduction of the clavicle fracture to restore perfusion
. Application of a shoulder spica cast
. Immediate operative exploration of the brachial plexus

Correct Answer & Explanation

. CT angiography of the left upper extremity

Explanation

The patient has a scapulothoracic dissociation, a highly lethal and devastating injury characterized by complete disruption of the scapulothoracic articulation. It is often accompanied by severe vascular (subclavian or axillary artery) and neurologic (brachial plexus avulsion) injuries. In a hemodynamically stable patient with an ischemic limb, CT angiography or formal angiography is critical to delineate the vascular injury before operative intervention (vascular bypass/repair). Closed reduction of the clavicle will not restore perfusion.

Question 4627

Topic: 2. Trauma

A 45-year-old male sustains a severe closed chest injury with multiple rib fractures and a scapular fracture. Which of the following is considered an absolute indication for operative fixation of a scapular fracture?

. Scapular body fracture with 10 mm of displacement
. Glenoid neck fracture with 20 degrees of angulation
. Intra-articular glenoid fracture with 5 mm step-off
. Coracoid base fracture without AC joint separation
. Spine of scapula fracture with 5 mm displacement

Correct Answer & Explanation

. Scapular body fracture with 10 mm of displacement

Explanation

Absolute indications for operative fixation of a scapula fracture include an intra-articular glenoid fracture with >4-5 mm of step-off, or significant displacement that leads to glenohumeral instability. Scapular body fractures, even with up to 15-20 mm of displacement, are generally treated non-operatively. Glenoid neck fractures are typically treated operatively if angulation exceeds 40 degrees or displacement is >1 cm.

Question 4628

Topic: 2. Trauma

A 72-year-old female sustains a 4-part proximal humerus fracture. Which of the following radiographic findings (Hertel criteria) is the most reliable predictor of humeral head ischemia?

. Displacement of the greater tuberosity > 1 cm
. Posterior medial hinge disruption > 2 mm
. Calcar length < 8 mm attached to the articular segment
. Angulation of the articular segment > 45 degrees
. Extension of the fracture into the bicipital groove

Correct Answer & Explanation

. Displacement of the greater tuberosity > 1 cm

Explanation

Hertel identified specific radiographic predictors for humeral head ischemia following proximal humerus fractures. The most significant predictors include a posteromedial metaphyseal head extension (calcar length) of <8 mm attached to the articular segment, disruption of the medial hinge >2 mm, and an anatomical neck fracture pattern. A calcar length <8 mm and medial hinge disruption >2 mm are highly predictive of ischemia, as the main blood supply (ascending branch of the anterior humeral circumflex artery) is compromised.

Question 4629

Topic: Upper Extremity Trauma

A 34-year-old male developed severe heterotopic ossification (HO) following open reduction and internal fixation of a terrible triad elbow injury 6 months ago. He complains of a rigid block to flexion and extension. Serum alkaline phosphatase levels are normal. Radiographs demonstrate mature trabeculated bone bridging the radiocapitellar joint. When is the most appropriate timing for surgical excision of the HO?

. Wait at least 12 months from the injury regardless of radiographic appearance
. Wait at least 18 months to ensure complete metabolic inactivity
. Proceed with excision now, as the bone appears mature radiographically and clinically
. Perform immediate manipulation under anesthesia
. Proceed with a total elbow arthroplasty

Correct Answer & Explanation

. Wait at least 12 months from the injury regardless of radiographic appearance

Explanation

Historical teaching recommended waiting 12-18 months before excising HO to allow it to "burn out" and prevent recurrence. However, modern evidence suggests that early excision (at 6 months or even earlier, often between 4-6 months) is safe and effective as long as the bone appears radiographically mature (trabeculated) and there is a clear clinical plateau in range of motion. Normalizing alkaline phosphatase or bone scans are no longer strictly required before excision.

Question 4630

Topic: 2. Trauma

A 25-year-old male sustains a closed mid-distal third spiral fracture of the humerus (Holstein-Lewis). At presentation, he has normal wrist and finger extension. Following closed reduction and splinting in the emergency department, he is unable to extend his wrist or fingers. What is the most appropriate management?

. Observation and electromyography (EMG) at 6 weeks
. Immediate surgical exploration of the radial nerve and fracture fixation
. Immediate removal of the splint and re-manipulation
. Ultrasound-guided nerve block for pain control
. Surgical exploration only if no recovery by 3 months

Correct Answer & Explanation

. Observation and electromyography (EMG) at 6 weeks

Explanation

A secondary radial nerve palsy (a deficit that develops after closed reduction or manipulation) is a widely accepted indication for immediate surgical exploration and fracture fixation. Primary radial nerve palsies (present on initial examination before manipulation) are generally observed. A Holstein-Lewis fracture is a spiral fracture of the distal third of the humerus, which carries a higher risk of radial nerve entrapment as the nerve pierces the lateral intermuscular septum.

Question 4631

Topic: 2. Trauma

A 50-year-old female is being evaluated for nonoperative treatment of a midshaft clavicle fracture. Which of the following factors has the highest predictive value for the development of a nonunion?

. Age > 40 years
. Female gender
. Displacement greater than 100% (width of the clavicle)
. Presence of a butterfly fragment
. Smoking

Correct Answer & Explanation

. Age > 40 years

Explanation

Displacement >100% (i.e., complete lack of cortical contact) is the single most significant predictive factor for nonunion in midshaft clavicle fractures treated nonoperatively. Other factors like advanced age, female gender, smoking, and comminution also increase the risk, but profound displacement (often combined with shortening >1.5 to 2 cm) has the strongest correlation with nonunion, making it a relative indication for ORIF.

Question 4632

Topic: 2. Trauma
A 35-year-old trauma patient presents with an ipsilateral midshaft clavicle fracture and a fracture of the scapular neck. This 'floating shoulder' disrupts the superior shoulder suspensory complex (SSSC). Which of the following best describes the anatomical components of the SSSC?
. Clavicle, coracoid, humerus, and acromioclavicular joint
. Glenoid, coracoid process, coracoclavicular ligaments, distal clavicle, acromioclavicular joint, and acromion
. Scapular body, clavicle, sternoclavicular joint, and glenohumeral joint
. Acromion, humeral head, greater tuberosity, and superior labrum
. Coracoid, short head of biceps, pectoralis minor, and coracoacromial ligament

Correct Answer & Explanation

. Glenoid, coracoid process, coracoclavicular ligaments, distal clavicle, acromioclavicular joint, and acromion

Explanation

The Superior Shoulder Suspensory Complex (SSSC) is a bone-and-soft-tissue ring that secures the upper extremity to the axial skeleton. It is composed of the glenoid, the coracoid process, the coracoclavicular (CC) ligaments, the distal clavicle, the acromioclavicular (AC) joint, and the acromion process. A 'floating shoulder' typically involves double disruptions of this ring (e.g., fractures of the surgical neck of the scapula and the clavicle).

Question 4633

Topic: 2. Trauma

A 78-year-old female with a history of severe osteoporosis and rheumatoid arthritis sustains a heavily comminuted, intra-articular distal humerus fracture (AO/OTA 13-C3). Based on current evidence, how does primary total elbow arthroplasty (TEA) compare to open reduction and internal fixation (ORIF) in this patient demographic?

. ORIF provides significantly better long-term functional scores
. TEA is associated with higher rates of nonunion
. TEA offers more reliable early clinical outcomes and fewer reoperations
. ORIF permits immediate unrestricted weight-bearing through the upper extremity
. TEA has a lower risk of ulnar neuropathy but higher risk of radial neuropathy

Correct Answer & Explanation

. ORIF provides significantly better long-term functional scores

Explanation

In elderly patients with severe osteopenia/osteoporosis and complex, comminuted intra-articular distal humerus fractures, primary Total Elbow Arthroplasty (TEA) has been shown to provide more reliable early and midterm functional outcomes with fewer complications and reoperations compared to ORIF. ORIF in osteoporotic bone is fraught with hardware failure, nonunion, and stiffness. TEA does restrict lifting to 5-10 lbs for life, which must be considered.

Question 4634

Topic: Upper Extremity Trauma

A 45-year-old carpenter presents with a 2-week history of a swollen, erythematous, and exquisitely tender bursa over his left olecranon. He denies fever, but the overlying skin is warm, and he has extreme pain with any degree of passive elbow flexion. Aspiration yields 5 cc of turbid fluid with a WBC count of 85,000 cells/mm3. What is the most appropriate initial management?

. Compressive wrapping and oral NSAIDs
. Corticosteroid injection into the bursa
. Intravenous antibiotics, and surgical bursectomy if no improvement in 24-48 hours
. Immediate arthroscopic synovectomy of the elbow joint
. Observation and warm compresses

Correct Answer & Explanation

. Compressive wrapping and oral NSAIDs

Explanation

The presentation (warmth, erythema, severe pain with motion, and a bursal aspirate WBC > 50,000 cells/mm3) is highly suggestive of septic olecranon bursitis. The initial management consists of prompt administration of antibiotics (intravenous for severe cases). If the condition does not improve or worsens within 24-48 hours of appropriate antibiotic therapy, or if there is impending skin necrosis, surgical excision of the bursa (bursectomy) is indicated. Corticosteroid injections are strictly contraindicated in the presence of infection.

Question 4635

Topic: 2. Trauma

A 19-year-old man sustains a closed, highly displaced midshaft clavicle fracture from a motorcycle accident. He has diminished radial and ulnar pulses with pallor of the hand. CT angiogram shows an intimal tear of the subclavian artery. At what anatomical location does the subclavian artery typically pass in relation to the scalene muscles?

. Anterior to the anterior scalene
. Between the anterior and middle scalene
. Between the middle and posterior scalene
. Posterior to the posterior scalene
. Through the substance of the anterior scalene

Correct Answer & Explanation

. Anterior to the anterior scalene

Explanation

The subclavian artery and the brachial plexus pass through the interscalene triangle, which is bordered anteriorly by the anterior scalene muscle, posteriorly by the middle scalene muscle, and inferiorly by the first rib. The subclavian vein passes anterior to the anterior scalene.

Question 4636

Topic: 2. Trauma

A 65-year-old woman is undergoing open reduction and internal fixation (ORIF) of a 3-part proximal humerus fracture. The surgeon is careful to avoid varus malreduction. Which of the following surgical techniques best prevents postoperative varus collapse?

. Placement of a lateral locking plate with unicortical screws
. Routine excision of the greater tuberosity
. Achieving medial cortical contact or placing inferomedial calcar screws
. Over-reduction into 15 degrees of valgus
. Resection of the biceps tendon

Correct Answer & Explanation

. Placement of a lateral locking plate with unicortical screws

Explanation

In the surgical management of proximal humerus fractures, restoring medial column support is critical to prevent varus collapse and screw cut-out. This can be achieved by anatomic reduction of the medial cortex, use of an intramedullary fibular strut allograft, or precise placement of inferomedial locking screws (calcar screws) into the inferomedial quadrant of the humeral head.

Question 4637

Topic: 2. Trauma

A 28-year-old motorcyclist is brought in after a high-speed collision. He has massive swelling over his left shoulder, an ipsilateral clavicle fracture, and an acromioclavicular separation. His arm is completely flail and pulseless. Chest radiograph reveals lateral displacement of the scapula compared to the contralateral side. What is the most critical initial step in management?

. Immediate exploration of the brachial plexus
. Emergent CT angiography and vascular surgery consultation
. Application of an arm sling and delayed MRI
. Immediate open reduction internal fixation of the clavicle
. Forequarter amputation

Correct Answer & Explanation

. Immediate exploration of the brachial plexus

Explanation

Scapulothoracic dissociation is a devastating, high-energy injury characterized by complete disruption of the scapulothoracic articulation. It is highly associated with massive vascular injuries (subclavian/axillary artery) and complete brachial plexus avulsions. Due to the high mortality rate from exsanguination, emergent vascular assessment (CT angiography) and life-saving hemorrhage control in conjunction with vascular surgery is the most critical initial step.

Question 4638

Topic: 2. Trauma



A 72-year-old woman sustains a 4-part proximal humerus fracture. Which of the following radiographic findings (Hertel criteria) is the most reliable predictor of subsequent avascular necrosis (AVN) of the humeral head?

. Metaphyseal head extension (calcar length) of 12 mm
. Integrity of the medial hinge (periosteum)
. Greater tuberosity displacement > 5 mm
. Angulation of the head > 45 degrees
. Metaphyseal head extension (calcar length) < 8 mm

Correct Answer & Explanation

. Metaphyseal head extension (calcar length) of 12 mm

Explanation

Hertel described reliable predictors of humeral head ischemia. The most important predictors for AVN in proximal humerus fractures include a short metaphyseal head extension (< 8 mm of calcar attached to the articular segment), disruption of the medial hinge (> 2 mm of displacement between the shaft and head), and an anatomic neck fracture pattern. An intact medial hinge and a calcar segment > 8 mm protect the blood supply (anterior and posterior circumflex humeral arteries).

Question 4639

Topic: 2. Trauma



An orthopedic surgeon is planning an olecranon osteotomy approach for open reduction and internal fixation of an AO type 13-C3 distal humerus fracture. To optimize the repair of the osteotomy at the end of the procedure and minimize articular step-off, what type of osteotomy is recommended?

. Transverse osteotomy at the deepest portion of the greater sigmoid notch
. Chevron osteotomy with the apex pointed distally into the bare area of the greater sigmoid notch
. Oblique osteotomy from dorsal-proximal to volar-distal
. Sagittal osteotomy splitting the olecranon
. Chevron osteotomy with the apex pointed proximally at the coronoid base

Correct Answer & Explanation

. Transverse osteotomy at the deepest portion of the greater sigmoid notch

Explanation

For a transolecranon approach to the distal humerus, a chevron (V-shaped) osteotomy with the apex directed distally is preferred. The osteotomy is directed into the 'bare area' (a region devoid of articular cartilage) of the greater sigmoid notch. This shape provides rotational stability and interdigitation upon repair, decreasing the risk of malunion and articular step-off.

Question 4640

Topic: 2. Trauma



A 65-year-old osteoporotic female sustains a highly comminuted, intra-articular distal humerus fracture (AO type 13-C3) that cannot be anatomically reconstructed. The surgeon opts for a Total Elbow Arthroplasty (TEA). Which of the following is an absolute contraindication to primary TEA for a distal humerus fracture?

. Age greater than 60 years
. Pre-existing rheumatoid arthritis
. Active infection or inadequate soft tissue coverage
. Concomitant radial head fracture
. Severe osteoporosis

Correct Answer & Explanation

. Age greater than 60 years

Explanation

Total elbow arthroplasty (TEA) is an excellent option for elderly patients with unreconstructible, comminuted distal humerus fractures. Osteoporosis and rheumatoid arthritis are indications or favorable conditions for TEA over ORIF. Active infection or inadequate soft-tissue coverage are absolute contraindications to joint arthroplasty due to the unacceptable risk of deep periprosthetic joint infection.

Test Yourself

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

On this Page