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 2141
Topic: 2. Trauma
A locking compression plate is applied as a bridging construct for a highly comminuted distal femur fracture. Which of the following screw configurations provides the most flexible construct to encourage secondary bone healing?
Correct Answer & Explanation
. Increasing the span of empty holes directly over the fracture zone.
Explanation
Omitting screws near the fracture site increases the working length of the bridge plate. A longer working length decreases construct stiffness, allowing for controlled interfragmentary micromotion that stimulates callus formation.
Question 2142
Topic: 2. Trauma
An orthopedic surgeon inserts a partially threaded lag screw across a medial malleolus fracture. The pullout strength of this screw from the surrounding cancellous bone is directly proportional to which of the following parameters?
Correct Answer & Explanation
. The outer thread diameter of the screw.
Explanation
Screw pullout strength is directly proportional to the volume of bone caught between the threads, which is dictated by the outer thread diameter and the length of thread engagement. The core diameter determines the screw's tensile and bending strength, not its pullout strength.
Question 2143
Topic: 2. Trauma
An oversized, unreamed intramedullary nail is forcefully driven into a narrow, unyielding tibial diaphysis, resulting in a sudden iatrogenic longitudinal diaphyseal split fracture. This complication is a result of exceeding the bone's biomechanical tolerance to which type of stress?
Correct Answer & Explanation
. Circumferential tensile (hoop) stress.
Explanation
Driving an oversized nail into a narrow canal generates outward radial forces that stretch the cortical bone. This induces high circumferential tensile stresses, commonly known as hoop stresses, leading to longitudinal split fractures when the bone's tensile limit is exceeded.
Question 2144
Topic: 2. Trauma
A 28-year-old cyclist falls directly onto his left shoulder, sustaining a completely displaced midshaft clavicle fracture with 2.5 cm of shortening and no cortical contact. If this fracture is managed nonoperatively in a sling, what is the most commonly reported complication compared to operative fixation?
Correct Answer & Explanation
. Nonunion
Explanation
Completely displaced midshaft clavicle fractures with greater than 2 cm of shortening have a significantly higher rate of nonunion and symptomatic malunion when treated nonoperatively, which is a major indication for open reduction and internal fixation.
Question 2145
Topic: 2. Trauma
A 45-year-old active male presents to the emergency department after a fall directly onto his shoulder. He complains of severe pain and inability to move his left arm. Radiographs are obtained, as shown below. Based on the provided images and the patient's profile, which of the following best describes the fracture and the most appropriate initial management strategy?
Correct Answer & Explanation
. C. A displaced Neer 2-part surgical neck fracture; managed with a sling, pain control, and consideration for ORIF given patient's age and activity level.
Explanation
Correct Answer: CThe radiographs (AP and axillary lateral views) demonstrate a displaced fracture through the surgical neck of the humerus. There is no clear involvement of the greater or lesser tuberosities as separate fragments, making it a Neer 2-part surgical neck fracture. Given the patient's age (45 years old) and active lifestyle, a displaced fracture of this nature warrants consideration for surgical intervention to optimize functional outcome and reduce the risk of malunion or nonunion. Initial management typically involves immobilization in a sling for comfort and pain control, followed by a thorough discussion of operative versus non-operative options. While non-operative treatment can be considered for patients with very low functional demands, it is less reliably associated with good functional outcomes in active, younger patients with displaced fractures.Option A is incorrectbecause the fracture is clearly displaced, not minimally displaced. While a sling is part of initial management, early range of motion would be inappropriate for a displaced fracture before definitive treatment.Option B is incorrectbecause the images do not clearly show a 3-part fracture involving the greater tuberosity as a separate, displaced fragment. Immediate ORIF is a treatment option, but the description of the fracture is inaccurate.Option D is incorrectbecause the fracture does not appear to be a 4-part fracture with significant head displacement, which would typically involve the anatomical neck, surgical neck, and both tuberosities, often with severe disruption of the blood supply. Reverse total shoulder arthroplasty is generally reserved for older patients with irreparable rotator cuff tears or complex 3- and 4-part fractures, especially in the elderly.Option E is incorrectbecause the fracture is displaced, not non-displaced, and it is a surgical neck fracture, not an anatomical neck fracture. Anatomical neck fractures carry a higher risk of osteonecrosis due to disruption of the blood supply to the humeral head.
Question 2146
Topic: 2. Trauma
Following the initial assessment, the 45-year-old active male with the displaced proximal humerus surgical neck fracture elects for surgical management. The orthopedic surgeon plans for open reduction internal fixation (ORIF) using a proximal humerus locking plate via a deltopectoral approach. During the patient counseling, which of the following statements regarding the rationale for surgical intervention in this specific patient is most accurate?
Correct Answer & Explanation
. For active, physiologically younger patients with displaced fractures, surgery offers a more reliable path to good functional outcomes and reduces the risk of painful malunion or nonunion compared to non-operative treatment.
Explanation
For active, physiologically younger patients with displaced proximal humerus fractures, surgical intervention (such as ORIF with a locking plate) is often recommended because it offers a more reliable means to achieve anatomical reduction and stable fixation, which in turn leads to better functional outcomes and a reduced risk of painful malunion or nonunion. While non-operative treatment can result in functional healing, it is less predictable for displaced fractures in this demographic.
Question 2147
Topic: 2. Trauma
Six months after successful open reduction internal fixation (ORIF) of his displaced proximal humerus surgical neck fracture, the 45-year-old active male reports persistent shoulder pain and limited range of motion, particularly in external rotation and abduction. Radiographs show good fracture healing and plate position. Physical examination reveals tenderness over the greater tuberosity and pain with resisted external rotation. Which of the following is the most likely cause of his ongoing symptoms?
Correct Answer & Explanation
. C. Subacromial impingement due to prominent hardware or malunion of the greater tuberosity
Explanation
Correct Answer: CPersistent shoulder pain and limited range of motion, especially with tenderness over the greater tuberosity and pain with resisted external rotation, 6 months after ORIF of a proximal humerus fracture, with good fracture healing and plate position, strongly suggest subacromial impingement. This can occur due to prominent hardware (e.g., screws extending superiorly, or the plate itself being too proud) or a subtle malunion of the greater tuberosity, which can impinge on the acromion during abduction and rotation. Pain with resisted external rotation specifically points towards rotator cuff involvement, which can be secondary to impingement.Option A (Avascular necrosis of the humeral head)typically presents with progressive pain and collapse of the humeral head, often visible on radiographs as increased density or flattening. While a risk, the description of 'good fracture healing and plate position' makes it less likely to be the primary cause of these specific symptoms at 6 months, especially if the fracture was a surgical neck fracture with intact blood supply to the head.Option B (Nonunion of the surgical neck fracture)would typically present with persistent pain, instability, and lack of radiographic healing. The question states 'good fracture healing,' ruling out nonunion.Option D (Axillary nerve palsy)would primarily manifest as deltoid weakness (difficulty with abduction) and sensory loss over the lateral shoulder. While it can cause weakness and some pain, the specific findings of tenderness over the greater tuberosity and pain with resisted external rotation point more towards a mechanical impingement issue rather than isolated nerve palsy.Option E (Adhesive capsulitis), or 'frozen shoulder,' can cause significant pain and global restriction of range of motion. While it can occur after shoulder trauma or surgery, the specific findings of tenderness over the greater tuberosity and pain with resisted external rotation, combined with the possibility of hardware prominence, make impingement a more specific and likely diagnosis in this context.
Question 2148
Topic: 2. Trauma
A 78-year-old sedentary female with low functional demands presents with a similar displaced proximal humerus surgical neck fracture. She has significant comorbidities, including severe osteoporosis and poorly controlled diabetes. Given her profile, which of the following management strategies would be most appropriate to discuss as a primary option?
Correct Answer & Explanation
. Non-operative management with a sling, early pendulum exercises, and pain control.
Explanation
For an elderly, sedentary patient with low functional demands and significant comorbidities (severe osteoporosis, poorly controlled diabetes), non-operative management with a sling, pain control, and early gentle pendulum exercises is often the most appropriate primary option. Surgical risks are higher in this population, and the potential benefits of surgery in terms of functional outcome may not outweigh these risks.
Question 2149
Topic: 2. Trauma
During the open reduction internal fixation (ORIF) of the displaced proximal humerus surgical neck fracture in the 45-year-old active male, the surgeon uses a proximal humerus locking plate. Which of the following is a primary biomechanical advantage of a locking plate system in this type of fracture compared to a conventional non-locking plate?
Correct Answer & Explanation
. B. It provides a fixed-angle construct, creating a more stable construct in osteoporotic bone.
Explanation
Correct Answer: BA primary biomechanical advantage of a locking plate system is that it provides a fixed-angle construct. The screws lock into the plate, creating a stable angular construct that acts like an internal fixator. This is particularly advantageous in osteoporotic bone or comminuted fractures where traditional screws might pull out. The locking mechanism allows the plate to act as a scaffold, supporting the articular segment and resisting collapse, rather than relying solely on screw purchase into potentially poor bone quality.Option A is incorrect. Conventional non-locking plates, especially with lag screws, are designed to achieve interfragmentary compression. While locking plates can achieve some compression with specific techniques (e.g., using a compression hole), their primary advantage is not greater compression but rather angular stability.Option C is incorrect. While locking plates can be more forgiving in terms of screw trajectory within the humeral head, precise screw placement is still crucial to avoid articular penetration and to maximize purchase in the strongest bone (e.g., calcar region). It does not mean less precise placement is acceptable for adequate fixation.Option D is incorrect. Locking plates provide rigid fixation, which generally limits micromotion at the fracture site. While some controlled micromotion can be beneficial for healing (relative stability), the primary goal of a locking plate in a displaced proximal humerus fracture is often absolute stability to maintain reduction and prevent collapse, especially in the metaphyseal region. Excessive micromotion would be detrimental.Option E is incorrect. While locking plates provide excellent stability, they do not eliminate the need for bone grafting in cases of significant metaphyseal comminution or bone loss, where grafting may still be necessary to promote healing and prevent collapse.
Question 2150
Topic: 2. Trauma
A 45-year-old male with a displaced proximal humerus surgical neck fracture, as depicted in the radiographs, is considering surgical intervention. During the discussion of potential complications, the surgeon emphasizes the risk of osteonecrosis of the humeral head. Which of the following fracture characteristics is most strongly associated with an increased risk of avascular necrosis (AVN) of the humeral head?
Correct Answer & Explanation
. C. Neer 4-part fracture with significant displacement
Explanation
Correct Answer: CA Neer 4-part fracture with significant displacement is most strongly associated with an increased risk of avascular necrosis (AVN) of the humeral head. In a 4-part fracture, the humeral head is completely separated from its muscular and capsular attachments, leading to a severe disruption of its blood supply, particularly the arcuate artery (branch of the anterior circumflex humeral artery) and posterior circumflex humeral artery. This devascularization significantly increases the risk of AVN.Option A (Isolated greater tuberosity fracture)typically does not significantly compromise the blood supply to the humeral head, and thus carries a low risk of AVN.Option B (Minimally displaced surgical neck fracture)generally has a low risk of AVN because the blood supply to the humeral head, primarily through the ascending branch of the anterior circumflex humeral artery and the posterior circumflex humeral artery, is often preserved.Option D (Isolated lesser tuberosity fracture)also typically does not significantly compromise the blood supply to the humeral head and has a low risk of AVN.Option E (Non-displaced anatomical neck fracture), while involving the anatomical neck, is non-displaced. However, even non-displaced anatomical neck fractures carry a higher risk of AVN than surgical neck fractures because the fracture line is closer to the main blood supply entering the head. But adisplaced4-part fracture represents a much more severe disruption of the blood supply, making it the highest risk category among the choices.
Question 2151
Topic: 2. Trauma
The 45-year-old active male, having undergone successful ORIF for his displaced proximal humerus surgical neck fracture, is now 6 weeks post-operative. He is progressing well with passive range of motion exercises. Which of the following is the most appropriate next step in his rehabilitation protocol?
Correct Answer & Explanation
. B. Initiation of active assisted range of motion (AAROM) exercises, while avoiding active abduction against gravity.
Explanation
Correct Answer: BAt 6 weeks post-ORIF for a proximal humerus fracture, with good healing progress, the typical rehabilitation protocol transitions from passive range of motion (PROM) to active assisted range of motion (AAROM). This allows the patient to begin engaging their muscles to assist movement, promoting muscle activation and preventing stiffness, while still protecting the healing fracture site from excessive stress. Active abduction against gravity is often avoided initially to protect the deltoid and rotator cuff repair (if any) and the healing fracture from significant shear forces.Option A is incorrect. Immediate return to full unrestricted activities is far too aggressive at 6 weeks post-ORIF and would risk re-fracture, hardware failure, or soft tissue injury.Option C is incorrect. Continued strict immobilization for another 6 weeks would lead to significant shoulder stiffness and poor functional outcomes. Early, controlled motion is crucial for shoulder rehabilitation.Option D is incorrect. Aggressive strengthening exercises are typically initiated much later in the rehabilitation process (e.g., 10-12 weeks or more post-op), after sufficient bone healing and restoration of basic range of motion. Starting too early could compromise fixation or healing.Option E is incorrect. Discontinuing physical therapy at 6 weeks would be detrimental to the patient's recovery. Rehabilitation for a proximal humerus fracture is a prolonged process, often lasting several months, to regain full strength and function.
Question 2152
Topic: 2. Trauma
A 45-year-old active male presents with a displaced proximal humerus surgical neck fracture, as shown in the images. He is concerned about the long-term implications of non-operative management, specifically the risk of malunion. Which of the following is the most common functional consequence of a significant malunion of a proximal humerus fracture?
Correct Answer & Explanation
. B. Impingement and limited range of motion, particularly abduction and external rotation
Explanation
Correct Answer: BA significant malunion of a proximal humerus fracture, especially with varus angulation or displacement of the tuberosities, can alter the normal anatomy of the shoulder joint. This often leads to subacromial impingement, where the humeral head or greater tuberosity abuts against the acromion during shoulder movement. This impingement causes pain and significantly limits the range of motion, particularly abduction and external rotation, which are critical for overhead activities and daily functions.Option A (Chronic elbow stiffness and pain)is not a direct consequence of a proximal humerus malunion. Elbow issues are more common with distal humerus fractures or prolonged immobilization of the elbow.Option C (Radial nerve palsy with wrist drop)is associated with humeral shaft fractures, not typically with proximal humerus malunion.Option D (Recurrent shoulder dislocation)is usually a consequence of glenohumeral instability, often due to labral tears or bony defects, not typically a direct result of a proximal humerus malunion, although severe malunion could theoretically contribute to altered joint mechanics.Option E (Brachial plexus injury with complete arm paralysis)is a severe acute complication of high-energy trauma or fracture-dislocations, not a chronic consequence of malunion.
Question 2153
Topic: 2. Trauma
The PROFHER trial compared surgical intervention (ORIF) to non-operative treatment for displaced proximal humerus fractures. For the 45-year-old active male with a displaced surgical neck fracture, how should the findings of the PROFHER trial influence the patient counseling regarding his treatment options?
Correct Answer & Explanation
. The trial indicates that there is no significant difference in patient-reported outcomes between surgical and non-surgical treatment at 2 years, suggesting that non-operative treatment is a reasonable option even for displaced fractures, especially if patient demands are lower or surgical risks are high.
Explanation
The PROFHER trial (Proximal Fracture of the Humerus: a Randomised Evaluation of Reverse Shoulder Arthroplasty) is a landmark study that found no significant difference in patient-reported outcomes (e.g., Oxford Shoulder Score) between surgical intervention (ORIF) and non-operative treatment for displaced proximal humerus fractures at 2 years. This is a crucial piece of evidence that informs shared decision-making.
Question 2154
Topic: 2. Trauma
A 45-year-old male sustains a direct fall onto his elbow, resulting in a displaced olecranon fracture. Which of the following structures is *least likely* to be directly involved in the primary function of the olecranon as an anatomical structure and lever arm for extension?
Correct Answer & Explanation
. Radial collateral ligament
Explanation
Correct Answer: DThe olecranon serves as the primary insertion point for the triceps brachii tendon (A), forming a critical lever arm for elbow extension. The anconeus muscle (B) originates from the lateral epicondyle and inserts onto the lateral aspect of the olecranon and proximal ulna, assisting in extension and stabilizing the ulnohumeral joint. The joint capsule (C) encompasses the ulnohumeral joint, and its integrity is often compromised in intra-articular fractures. The ulnar nerve (E) runs in the cubital tunnel posterior to the medial epicondyle, making it vulnerable to injury with olecranon fractures or surgical approaches. The radial collateral ligament (D) is located laterally and stabilizes the humeroradial and proximal ulnar joints against varus stress, having a less direct role in theprimary functionof the olecranon's lever arm for extension compared to the other options. While indirect involvement or associated injury is possible, its direct contribution to the olecranon's lever arm function is less central.
Question 2155
Topic: 2. Trauma
A 68-year-old female presents with an olecranon fracture classified as Mayo Type IIB. Which characteristic best describes this specific fracture pattern?
Correct Answer & Explanation
. Displaced, stable, comminuted.
Explanation
Correct Answer: EThe Mayo Classification for olecranon fractures categorizes them based on displacement, stability, and comminution. Type II fractures are displaced. Subtype IIB specifically denotes a displaced, comminuted, yet stable fracture. Stability implies the ulnohumeral joint remains congruent despite the fracture, meaning the fracture is not associated with elbow instability or dislocation.
Question 2156
Topic: 2. Trauma
A patient falls directly onto the point of their elbow. Which of the following olecranon fracture patterns is *most commonly* associated with this mechanism?
Correct Answer & Explanation
. Highly comminuted fracture with articular involvement
Explanation
Correct Answer: CA direct fall onto the point of the elbow typically results in high-energy trauma, driving the olecranon directly against the trochlea. This commonly leads to highly comminuted fractures with significant articular involvement (C) due to the crushing force. Avulsion fractures (D) are more often due to indirect mechanisms (sudden triceps contraction). Transverse non-displaced fractures (A) or simple oblique fractures (B) can occur with direct trauma but are less characteristic of high-energy impact onto the olecranon apex. Anterior coronoid fractures (E) are often associated with posterior dislocations and varus posteromedial rotatory instability, not typically a direct impact mechanism to the olecranon apex itself.
Question 2157
Topic: 2. Trauma
A 32-year-old male presents after a motorcycle accident with a suspected olecranon fracture. On examination, he has a visible deformity, swelling, and ecchymosis over the posterior elbow. He is unable to actively extend his elbow against gravity. What is the *most critical* initial finding to assess regarding ulnohumeral joint stability?
Correct Answer & Explanation
. Palpation for a palpable gap at the fracture site
Explanation
Correct Answer: BWhile all options are important, the question specifically asks for the 'most critical initial finding to assess regarding ulnohumeral joint stability' in the context of asuspected olecranon fracture. A palpable gap at the fracture site (B) directly indicates significant displacement of the olecranon, which often correlates with profound disruption of the triceps mechanism and compromise of the ulnohumeral joint's posterior stability. The inability to actively extend the elbow against gravity is already mentioned, which points to disruption. Varus/valgus stress testing (D) assesses collateral ligament integrity, which is important, but a displaced olecranon fragment itself significantly compromises the posterior stability. Assessment of ulnar nerve function (C) and distal neurovascular status (E) are crucial for managing complications but do not directly assess ulnohumeralmechanical stabilityrelated to the fracture pattern itself. Passive elbow flexion (A) provides information about potential stiffness but not acute stability.
Question 2158
Topic: 2. Trauma
Which of the following conditions is an absolute contraindication to non-operative management of an olecranon fracture?
Correct Answer & Explanation
. Open fracture with skin breach
Explanation
Correct Answer: DAn open fracture (D) with a breach in the skin over the fracture site is an absolute contraindication to non-operative management. This is due to the extremely high risk of infection, requiring urgent surgical debridement, irrigation, antibiotics, and stabilization. Patient preference (A) is a relative factor. An elderly, low-demand patient (B) or a completely non-displaced fracture (C) are typically indicationsfornon-operative management. Mild comminution without articular step-off (E) can sometimes be managed non-operatively, especially if stable and nondisplaced.
Question 2159
Topic: 2. Trauma
A 40-year-old healthy male sustains a simple transverse, displaced olecranon fracture with intact articular surface. Which surgical technique is generally considered the *gold standard* for fixation in this scenario?
Correct Answer & Explanation
. Tension band wiring
Explanation
Correct Answer: DFor simple transverse, displaced olecranon fractures (especially Mayo Type IIA) with intact articular surface and good bone stock, tension band wiring (D) is considered the gold standard. It effectively converts tensile forces from the triceps pull into compressive forces at the fracture site, promoting healing and allowing for early mobilization. Plate and screw fixation (A) is preferred for comminuted fractures, unstable fractures, or osteoporotic bone. Intramedullary screw fixation (B) has limited, specific indications. Excision of the proximal fragment (C) is reserved for very small, distal fragments in low-demand patients or severely comminuted segments that cannot be reconstructed. Total elbow arthroplasty (E) is a salvage procedure for highly complex, unreconstructable fractures, especially in the elderly.
Question 2160
Topic: 2. Trauma
When considering plate fixation for an olecranon fracture, which of the following scenarios would *most strongly* indicate a locking plate over a conventional compression plate?
Correct Answer & Explanation
. Highly comminuted fracture in an osteoporotic elderly patient
Explanation
Correct Answer: CLocking plates provide angular stability independent of plate-bone compression, making them particularly advantageous in osteoporotic bone or highly comminuted fractures (C) where conventional screw purchase may be inadequate. In these cases, locking screws 'lock' into the plate, creating a fixed-angle construct that resists collapse and provides stable fixation even with poor bone quality. Simple transverse (A) or oblique fractures (B) in good bone quality often respond well to tension band wiring or conventional compression plating. Avulsion fractures (D) are typically managed with tension band wiring or direct suture. Distal ulna shaft extension (E) would indicate a longer plate but not necessarily a locking plate without other factors.
Test Yourself
Switch to an interactive, timed exam simulation to truly master this topic.