Menu

9. Shoulder and Elbow MCQs

Practice Set 145 of 197

This practice set contains high-yield board review questions covering key concepts in 9. Shoulder and Elbow. Each clinical scenario is designed to test your diagnostic and management skills relevant to this subspecialty.

Question 2881

Topic: 9. Shoulder and Elbow

A 50-year-old woman develops a rapidly progressive, destructive arthropathy of her right elbow without significant trauma. Neurological exam reveals absent reflexes and cape-like sensory loss. MRI confirms a large cervical syrinx. What is the most appropriate initial management for her elbow?

. Total elbow arthroplasty
. Elbow arthrodesis
. Splinting and joint protection while addressing the neurological lesion
. Intra-articular corticosteroid injection
. Open reduction and internal fixation of the fragmented joint

Correct Answer & Explanation

. Splinting and joint protection while addressing the neurological lesion

Explanation

The patient has a Charcot elbow secondary to syringomyelia. Surgical interventions like arthroplasty, arthrodesis, or ORIF in Charcot joints have notoriously high failure and complication rates. Initial management involves bracing/protection and neurosurgical evaluation of the syrinx.

Question 2882

Topic: 9. Shoulder and Elbow

A 45-year-old female presents with painless swelling, crepitus, and instability of the right shoulder. Radiographs show severe destruction of the glenohumeral joint with massive osseous debris but no signs of infection. Neurological exam reveals a loss of pain and temperature sensation in the upper extremities. What is the primary pathophysiology?

. Dorsal column degeneration from tertiary syphilis
. Cavitation of the central spinal cord
. Avascular necrosis of the humeral head secondary to corticosteroids
. Amyloid deposition in the articular cartilage
. Infection with an indolent organism such as Cutibacterium acnes

Correct Answer & Explanation

. Cavitation of the central spinal cord

Explanation

This patient has neuropathic (Charcot) arthropathy of the shoulder secondary to syringomyelia. Cavitation of the central spinal cord (syrinx) damages crossing spinothalamic tracts in the anterior white commissure, leading to the classic "cape-like" loss of pain and temperature.

Question 2883

Topic: 9. Shoulder and Elbow

A 40-year-old male with a history of a chronic, untreated cervical syrinx presents with a massively swollen, painless right shoulder. Radiographs demonstrate severe joint destruction, bony debris, and disorganization of the glenohumeral joint. Infection is ruled out via aspiration. What is the fundamental pathophysiology driving this joint destruction?

. Autoimmune targeting of type II collagen in the articular cartilage
. Deposition of monosodium urate crystals causing a cytokine storm
. Loss of protective proprioception and nociception leading to repetitive microtrauma
. Ischemic necrosis of the humeral head secondary to autonomic vascular dysregulation
. Hyperproliferation of the synovial membrane secondary to increased beta-catenin signaling

Correct Answer & Explanation

. Loss of protective proprioception and nociception leading to repetitive microtrauma

Explanation

This patient has a neuropathic (Charcot) arthropathy of the shoulder, classically associated with syringomyelia in the upper extremity. The underlying mechanism is the disruption of pain and proprioceptive pathways, leading to unrecognized repetitive microtrauma and progressive joint destruction.

Question 2884

Topic: 9. Shoulder and Elbow

In differentiating the diffuse cutaneous form of systemic sclerosis from the limited form (CREST syndrome), which of the following clinical features is highly typical of the diffuse form?

. Early onset of severe interstitial lung disease (pulmonary fibrosis)
. Late onset of internal organ involvement
. Predominant involvement of skin isolated distal to the elbows and knees
. High association with anti-centromere antibodies
. Presence of esophageal dysmotility as the sole visceral manifestation

Correct Answer & Explanation

. Early onset of severe interstitial lung disease (pulmonary fibrosis)

Explanation

Diffuse cutaneous systemic sclerosis is characterized by rapid progression of skin thickening (both proximal and distal) and early, severe internal organ involvement. This notably includes interstitial lung disease (pulmonary fibrosis) and scleroderma renal crisis.

Question 2885

Topic: Elbow & Forearm

In a patient with Multiple Hereditary Exostoses (MHE), which of the following forearm deformities is most characteristic of the 'Bessel-Hagen' deformity?

. Radial shortening with ulnar translocation of the carpus
. Ulnar shortening, increased radial bow, and progressive radial head dislocation
. Madelung deformity with volar-ulnar tilt of the distal radius
. Isolated hypertrophy of the radial styloid
. Synostosis of the proximal radius and ulna

Correct Answer & Explanation

. Ulnar shortening, increased radial bow, and progressive radial head dislocation

Explanation

Correct Answer: BThe Bessel-Hagen deformity in MHE is characterized by disproportionate shortening of the ulna (due to its smaller diameter and greater relative growth plate involvement), which leads to secondary bowing of the radius, ulnar tilt of the distal radial articular surface, and often, proximal translocation (dislocation) of the radial head.

Question 2886

Topic: Elbow & Forearm
Which of the following describes a capitellar fracture according to the Bryan and Morrey classification?
. Type I: Coronal shear fracture of the capitellum with significant displacement
. Type II: Fracture involving both the capitellum and the trochlea (bicondylar)
. Type III: Fracture of the entire capitellum with a large amount of lateral epicondyle
. Type IV: Comminuted fracture of the entire distal humerus
. Type I: Coronal shear fracture of the capitellum without displacement

Correct Answer & Explanation

. Type I: Coronal shear fracture of the capitellum with significant displacement

Explanation

The Bryan and Morrey classification is commonly used for capitellar fractures. Type I is a complete coronal shear fracture of the capitellum that is displaced. Type II (Hahn-Steinthal) is a larger fragment including subchondral bone but often nondisplaced. Type III (Kocher-Lorenz) is an articular cartilage-only fracture. Type IV is for fractures involving the trochlea as well (Cunha-Bryan).

Question 2887

Topic: 9. Shoulder and Elbow

When assessing a distal humerus fracture, what specific radiographic view is crucial for evaluating articular extension, particularly for coronal shear fractures?

. Anteroposterior (AP) view
. Lateral view
. Oblique views (internal and external)
. Axial view of the capitellum (often part of CT)
. True lateral of the elbow with 90-degree flexion

Correct Answer & Explanation

. True lateral of the elbow with 90-degree flexion

Explanation

While AP and lateral views are standard, a true lateral view of the elbow with the elbow flexed to 90 degrees is critical for assessing articular extension and the presence of coronal shear fractures (e.g., capitellar fractures), which can be subtle on other views. This view provides an optimal profile of the trochlea and capitellum. While axial views of the capitellum are often obtained with a CT, the question refers to radiographic views. Oblique views can be helpful but are not as specific for articular extension as a true lateral.

Question 2888

Topic: 9. Shoulder and Elbow

Regarding the elbow's vascular supply, which arterial branches form an important collateral network around the elbow, critical for maintaining perfusion after injury or surgery?

. Deep femoral artery and popliteal artery branches
. Axillary artery and circumflex humeral arteries
. Radial recurrent, ulnar recurrent, and superior/inferior ulnar collateral arteries
. Posterior interosseous artery and anterior interosseous artery
. Subclavian artery and vertebral artery

Correct Answer & Explanation

. Radial recurrent, ulnar recurrent, and superior/inferior ulnar collateral arteries

Explanation

The elbow joint has a rich collateral arterial network, primarily formed by branches of the brachial artery. Key contributors include the radial recurrent artery (from radial), ulnar recurrent arteries (anterior and posterior from ulnar), and the superior and inferior ulnar collateral arteries (from brachial). These form an anastomosis around the joint, crucial for maintaining blood supply, especially when the main brachial artery or one of its major branches is compromised by injury or clamped during surgery. The other options refer to different anatomical regions or main trunk arteries, not the direct collateral network around the elbow.

Question 2889

Topic: 9. Shoulder and Elbow

A 35-year-old male sustains a posterior elbow dislocation after falling onto an outstretched hand. Radiographs confirm a simple posterior dislocation with no obvious fractures. Neurovascular exam is intact. What is the MOST appropriate initial management step post-reduction for this patient?

. Immediate surgical exploration to assess ligamentous integrity.
. Casting in 90 degrees of flexion and pronation for 6 weeks.
. Application of a hinged elbow brace, initiating early range of motion within the stable arc.
. Immobilization in full extension for 3 weeks to allow capsular healing.
. Referral for immediate MRI to rule out occult chondral injuries.

Correct Answer & Explanation

. Application of a hinged elbow brace, initiating early range of motion within the stable arc.

Explanation

For a simple, stable posterior elbow dislocation after successful reduction and confirmation of stability through a range of motion, the most appropriate management is early range of motion (ROM) within a stable arc, typically initiated with a hinged elbow brace. This prevents stiffness, a common complication, while protecting the healing ligaments. Immobilization for prolonged periods (e.g., 6 weeks) increases the risk of severe stiffness and heterotopic ossification. Full extension promotes posterior subluxation and is biomechanically unstable. Surgical exploration is generally reserved for complex dislocations or irreducible dislocations. MRI is not routinely indicated for simple, stable dislocations.

Question 2890

Topic: Elbow & Forearm
Which of the following ligamentous structures is considered the primary static stabilizer against varus stress in the elbow?
. Anterior bundle of the medial ulnar collateral ligament (MUCL)
. Lateral ulnar collateral ligament (LUCL)
. Radial collateral ligament (RCL)
. Posterior bundle of the medial ulnar collateral ligament (MUCL)
. Annular ligament

Correct Answer & Explanation

. Radial collateral ligament (RCL)

Explanation

The Radial Collateral Ligament (RCL) complex, specifically the Radial Collateral Ligament proper, is the primary static stabilizer against varus stress. The Anterior Bundle of the Medial Ulnar Collateral Ligament (MUCL) is the primary stabilizer against valgus stress. The Lateral Ulnar Collateral Ligament (LUCL) is critical for posterolateral rotatory stability, preventing subluxation of the ulna and radius from the humerus. The Annular ligament stabilizes the radial head against the ulna but is not a primary varus stabilizer for the humeroulnar joint. The posterior bundle of the MUCL contributes to valgus stability but is less critical than the anterior bundle.

Question 2891

Topic: Elbow & Forearm

A patient presents with an elbow dislocation associated with a radial head fracture and a coronoid process fracture. This constellation of injuries is classically termed a 'terrible triad' injury. Which aspect of this injury typically dictates the need for surgical intervention and directly impacts the stability of the elbow after reduction?

. The extent of the radial head comminution.
. The degree of soft tissue swelling.
. The presence of an associated ulnar nerve palsy.
. The integrity of the lateral ulnar collateral ligament (LUCL) complex.
. The specific location and size of the coronoid fracture.

Correct Answer & Explanation

. The integrity of the lateral ulnar collateral ligament (LUCL) complex.

Explanation

While all components contribute to the 'terrible triad,' the posterolateral rotatory instability caused by disruption of the lateral ulnar collateral ligament (LUCL) complex is the fundamental issue that dictates the need for surgical stabilization and affects post-reduction stability. The LUCL is crucial in preventing posterolateral rotatory instability, which is a common pattern in terrible triad injuries. Coronoid fractures (especially involving the sublime tubercle) and radial head fractures contribute significantly to instability, but the LUCL injury is often the primary driver for surgical intervention to restore stability. Radial head comminution influences the choice of radial head management (repair vs. replacement), and swelling is a consequence, not a primary driver of instability. Ulnar nerve palsy is a potential complication but not the defining feature dictating stability management.

Question 2892

Topic: 9. Shoulder and Elbow

During closed reduction of a posterior elbow dislocation, what is the MOST effective maneuver to achieve reduction?

. Direct posterior force applied to the olecranon with the elbow in extension.
. Hyperflexion of the elbow with concomitant axial traction.
. Longitudinal traction with forearm supination, followed by gentle flexion and direct anterior pressure on the olecranon.
. Application of a valgus stress while simultaneously extending the elbow.
. Vigorous adduction with rotation of the forearm.

Correct Answer & Explanation

. Longitudinal traction with forearm supination, followed by gentle flexion and direct anterior pressure on the olecranon.

Explanation

The most effective and commonly taught method for closed reduction of a posterior elbow dislocation involves longitudinal traction applied to the forearm, with the elbow slightly flexed. Concurrently, an anteriorly directed force is applied to the olecranon to disengage it from the humerus. The forearm is often supinated to 'unlock' the radial head from the capitellum, followed by gentle flexion to complete the reduction. Option C correctly describes this. Direct posterior force (Option A) would worsen the dislocation. Hyperflexion alone (Option B) is insufficient without traction and anterior pressure. Valgus stress (Option D) or vigorous adduction (Option E) may cause further injury to the collateral ligaments or neurovascular structures.

Question 2893

Topic: 9. Shoulder and Elbow

Following successful closed reduction of a simple posterior elbow dislocation, the elbow is found to be unstable in extension beyond 30 degrees, but stable at 60 degrees of flexion and beyond. What is the MOST appropriate next step in management?

. Immediate operative repair of the lateral collateral ligament.
. Begin immediate active range of motion exercises in all planes.
. Immobilize in a long arm cast at 30 degrees of flexion for 4 weeks.
. Apply a hinged elbow brace and allow active range of motion from 30 to 90 degrees of flexion.
. Perform a repeat reduction attempt with increased force.

Correct Answer & Explanation

. Immobilize in a long arm cast at 30 degrees of flexion for 4 weeks.

Explanation

The finding of instability in extension beyond 30 degrees (but stability at 60 degrees) indicates a degree of posterolateral rotatory instability, often due to a stretched or partially torn lateral collateral ligament complex. While a hinged brace with protected motion is often used for stable simple dislocations, persistent instability into extension suggests the need for more protection. Immobilization in a long arm cast at 30 degrees of flexion for 4 weeks is a reasonable approach to allow for ligamentous healing, keeping the elbow out of the unstable arc. Immediate surgical repair is generally reserved for more complex dislocations or profound instability. Immediate active ROM would jeopardize healing. Repeat reduction is unnecessary if the elbow is already reduced.

Question 2894

Topic: 9. Shoulder and Elbow
A 40-year-old male presents with an open posterior elbow dislocation after a high-energy fall. The wound is clean but communicates with the joint. What is the priority management step after initial wound irrigation and debridement in the emergency department?
. Closed reduction and immobilization in a long arm cast
. Application of an external fixator across the elbow joint
. Surgical exploration, formal irrigation, debridement, and primary repair of disrupted structures
. Administration of systemic antibiotics and delayed surgical intervention
. Immediate elbow arthroplasty to restore joint congruity

Correct Answer & Explanation

. Surgical exploration, formal irrigation, debridement, and primary repair of disrupted structures

Explanation

For an open elbow dislocation, after initial wound care and administration of prophylactic antibiotics, the priority management is surgical exploration, formal irrigation, debridement, and reduction in the operating theatre. This allows for thorough cleaning of the joint, assessment of associated injuries (fractures, neurovascular structures, ligaments), and appropriate management of the open wound. While primary repair of disrupted structures might be considered, the primary goal is to prevent infection and achieve reduction. External fixation (Option B) may be used for highly unstable cases or those with significant soft tissue compromise, but not as the initial definitive step for an open dislocation. Closed reduction alone (Option A) is insufficient for an open injury. Delayed surgery (Option D) increases infection risk. Arthroplasty (Option E) is not an acute management option.

Question 2895

Topic: Elbow & Forearm

A 60-year-old patient undergoes reduction of a posterior elbow dislocation. Post-reduction radiographs show excellent congruity. However, the elbow remains grossly unstable in all planes. What is the MOST likely underlying reason for this persistent instability?

. Inadequate muscle relaxation during reduction.
. Missed radial head fracture.
. Complete disruption of both medial and lateral collateral ligament complexes.
. Undiagnosed osteochondral fragment within the joint.
. Early development of heterotopic ossification.

Correct Answer & Explanation

. Complete disruption of both medial and lateral collateral ligament complexes.

Explanation

Gross instability in all planes after reduction of an elbow dislocation, despite good radiographic congruity, strongly suggests complete disruption of both the medial (ulnar) and lateral collateral ligament complexes. While other factors like radial head or coronoid fractures contribute to instability, isolated injuries to these structures typically result in more specific patterns of instability (e.g., posterolateral rotatory instability with LUCL injury, valgus instability with MUCL injury). When both major collateral complexes are significantly compromised, the elbow becomes globally unstable. Inadequate muscle relaxation (Option A) would hinder reduction, not cause post-reduction global instability. A missed radial head fracture (Option B) would lead to more specific instability patterns (posterolateral rotatory). An osteochondral fragment (Option D) might block reduction or cause mechanical symptoms but not global instability. Heterotopic ossification (Option E) is a late complication causing stiffness, not acute instability.

Question 2896

Topic: Elbow & Forearm

What is the primary role of the coronoid process in elbow stability?

. It serves as the attachment point for the lateral collateral ligament.
. It acts as the primary bony block to valgus stress.
. It provides the main resistance to varus stress.
. It is a critical anterior buttress, preventing posterior subluxation of the ulna on the humerus.
. It enhances radial head articulation with the capitellum.

Correct Answer & Explanation

. It is a critical anterior buttress, preventing posterior subluxation of the ulna on the humerus.

Explanation

The coronoid process acts as a critical anterior buttress, preventing posterior subluxation and dislocation of the ulna relative to the humerus. Fractures of the coronoid process, especially larger fragments, significantly compromise elbow stability, particularly in conjunction with collateral ligament injuries. It is not the primary attachment for the lateral collateral ligament (Option A), nor is it the main bony block to valgus (Option B) or varus (Option C) stress (these are more related to the olecranon and radial head articulation with the capitellum, and the collateral ligaments). It does not primarily enhance radial head articulation (Option E), though it contributes to overall joint congruity.

Question 2897

Topic: 9. Shoulder and Elbow

A 28-year-old active male suffers a posterior elbow dislocation that is irreducible by closed means in the emergency department despite adequate sedation. What is the MOST likely cause of irreducibility in this scenario?

. Interposition of the ulnar nerve.
. Chronic dislocation that has fibrosed.
. Entrapment of the medial epicondyle within the joint.
. A large associated coronoid fracture fragment blocking reduction.
. Significant heterotopic ossification preventing motion.

Correct Answer & Explanation

. Entrapment of the medial epicondyle within the joint.

Explanation

The most common cause of an irreducible posterior elbow dislocation is entrapment of the medial epicondyle (or occasionally the lateral epicondyle) within the joint, acting as a block to reduction. This is especially true in younger patients where the physis is not yet fused. A large coronoid fracture fragment (Option D) can also block reduction, but less commonly than soft tissue or epicondyle entrapment. Ulnar nerve interposition (Option A) is rare but possible. Chronic dislocation (Option B) implies a prolonged duration, which isn't specified here and leads to fibrous ankylosis rather than acute irreducibility. Heterotopic ossification (Option E) is a late complication leading to stiffness, not acute irreducibility.

Question 2898

Topic: 9. Shoulder and Elbow

Which radiographic view is essential for adequately assessing the coronoid process after an elbow dislocation?

. Anterior-posterior (AP) view.
. Lateral view.
. Oblique views (internal and external).
. Stress radiographs in valgus and varus.
. Distal humerus axial view.

Correct Answer & Explanation

. Lateral view.

Explanation

The lateral view of the elbow is the most critical for assessing the coronoid process and its involvement in fractures associated with elbow dislocations. While AP and oblique views (Options A and C) provide supplementary information, the coronoid is best visualized as an anterior buttress on the true lateral view. Stress radiographs (Option D) are for instability assessment, not fracture morphology. A distal humerus axial view (Option E) is not a standard view for the coronoid.

Question 2899

Topic: 9. Shoulder and Elbow
What is the primary concern when managing a chronic, unreduced elbow dislocation (present for >3 weeks)?
. High risk of ulnar nerve palsy post-reduction.
. Increased likelihood of avascular necrosis of the radial head.
. Significant soft tissue contracture and bone remodeling, making closed reduction difficult and potentially dangerous.
. Development of post-traumatic arthritis, necessitating early arthroplasty.
. Inability to achieve stable fixation with internal constructs.

Correct Answer & Explanation

. Significant soft tissue contracture and bone remodeling, making closed reduction difficult and potentially dangerous.

Explanation

For chronic unreduced elbow dislocations, significant soft tissue contracture, adhesions, and potential bone remodeling (e.g., heterotopic ossification, articular cartilage changes) make closed reduction very difficult and prone to complications such as neurovascular injury, iatrogenic fractures, or skin avulsion. Open reduction and often extensive soft tissue release are typically required. While ulnar nerve palsy is a risk, the overarching challenge is the established contracture.

Question 2900

Topic: Elbow & Forearm

A patient presents with a 'terrible triad' injury of the elbow. Which surgical approach is generally preferred for addressing all components (radial head, coronoid, and lateral collateral ligament) in a single setting?

. Medial approach to address the coronoid and medial collateral ligament.
. Direct posterior approach to the olecranon.
. Posterolateral approach with conversion to a Kocher interval.
. Anterior approach to decompress the median nerve.
. Anconeus interval approach, avoiding muscle dissection.

Correct Answer & Explanation

. Posterolateral approach with conversion to a Kocher interval.

Explanation

For a terrible triad injury, a posterolateral approach (often via the Kocher interval between the anconeus and extensor carpi ulnaris) is generally preferred. This approach allows for excellent visualization and access to the radial head, the lateral ulnar collateral ligament (LUCL) for repair, and the coronoid process (especially anteromedial facets) can often be accessed through this approach, potentially through a window created in the anconeus muscle or by extending the interval. A medial approach (Option A) would not allow access to the radial head or LUCL. A direct posterior approach (Option B) is less ideal for radial head or LUCL. Anterior (Option D) or anconeus interval (Option E) approaches are less comprehensive for all components of the triad.

Test Yourself

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

On this Page