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 2281
Topic: 9. Shoulder and Elbow
A 72-year-old woman with pseudoparalysis of the shoulder secondary to a massive, irreparable rotator cuff tear undergoes a reverse total shoulder arthroplasty. How does this specific implant design alter the biomechanics of the shoulder joint to restore active elevation?
Correct Answer & Explanation
. Lateralizes the center of rotation to increase the supraspinatus moment arm
Explanation
The reverse total shoulder arthroplasty (RTSA) is designed to medialise the center of rotation (placing it at the glenoid bone-implant interface) and distalize the humerus. Medializing the center of rotation recruits more deltoid fibers for elevation and increases the deltoid's moment arm. Distalizing the humerus tensions the deltoid, further increasing its efficiency to compensate for the absent rotator cuff.
Question 2282
Topic: Elbow & Forearm
A 45-year-old man falls on an outstretched hand and sustains a 'terrible triad' injury of the elbow. Imaging confirms a posterior elbow dislocation, a comminuted radial head fracture, and a Regan-Morrey Type 2 coronoid fracture. During surgical reconstruction, after addressing the radial head and repairing the anterior capsule/coronoid, the elbow remains unstable to varus stress and tends to subluxate posterolaterally. Which of the following structures must be repaired next to restore stability?
Correct Answer & Explanation
. Lateral ulnar collateral ligament (LUCL)
Explanation
The standard surgical sequence for a terrible triad injury of the elbow involves: 1) fixing or replacing the radial head, 2) repairing the coronoid fracture or anterior capsule, 3) repairing the lateral collateral ligament (specifically the LUCL) to the lateral epicondyle, and 4) evaluating and repairing the medial collateral ligament only if the elbow remains unstable in extension after the lateral side is fixed. Posterolateral rotatory instability is prevented by restoring the LUCL.
Question 2283
Topic: 9. Shoulder and Elbow
A 40-year-old man falls from a ladder and sustains an elbow injury. Imaging reveals a posterior elbow dislocation, a comminuted radial head fracture, and a type II coronoid fracture. The patient is taken to the operating room for surgical stabilization. What is the generally recommended sequence of reconstruction for this specific pattern of injury?
The 'terrible triad' of the elbow consists of an elbow dislocation, a radial head fracture, and a coronoid fracture. The standard surgical protocol established to restore stability typically progresses from deep to superficial, moving from the inside out. The sequence generally recommended is: 1) Fixation of the coronoid fracture (restoring the anterior buttress), 2) Repair or replacement of the radial head (restoring the anterior/valgus buttress), and 3) Repair of the lateral collateral ligament (LCL) complex. MCL repair is only considered if the elbow remains unstable in extension after these three steps have been completed.
Question 2284
Topic: Shoulder Arthroplasty & Arthritis
A 78-year-old right-hand-dominant woman sustains a closed right proximal humerus fracture after a mechanical fall. Radiographs demonstrate a 4-part fracture pattern with a head-split component, severe comminution of the tuberosities, and significant osteopenia. She lives independently but leads a sedentary lifestyle. What is the most appropriate surgical management to provide the most predictable pain relief and restoration of forward elevation?
Correct Answer & Explanation
. Nonoperative management with early passive range of motion
Explanation
In elderly patients with poor bone stock (osteopenia/osteoporosis) and complex 4-part proximal humerus fractures, reverse total shoulder arthroplasty (RTSA) has been shown to provide more predictable outcomes regarding pain relief and functional recovery (specifically forward elevation) compared to hemiarthroplasty or ORIF. The functional success of hemiarthroplasty relies heavily on anatomic tuberosity healing, which is highly unpredictable in the elderly with comminuted, osteoporotic bone. ORIF in this demographic carries an unacceptably high rate of screw cutout, avascular necrosis, and hardware failure. RTSA allows the deltoid to elevate the arm even in the absence of a functioning rotator cuff or healed tuberosities.
Question 2285
Topic: Shoulder Arthroplasty & Arthritis
Which of the following component design modifications or surgical techniques in reverse total shoulder arthroplasty has been shown to decrease the incidence of scapular notching?
Correct Answer & Explanation
. Superior placement of the glenosphere
Explanation
Scapular notching is a common mechanical complication of reverse total shoulder arthroplasty (RTSA) occurring when the medial aspect of the humeral component impinges against the inferior scapular neck during adduction. Techniques to minimize it include inferior placement of the baseplate (overhanging the inferior rim), inferior tilt of the baseplate, lateralization of the glenosphere (or center of rotation), using a larger glenosphere, and decreasing the neck-shaft angle of the humeral component (e.g., to 135 or 145 degrees).
Question 2286
Topic: Elbow & Forearm
A 42-year-old man falls on his outstretched hand and sustains a "terrible triad" injury of the elbow. Which of the following represents the most widely accepted sequence of surgical reconstruction for this specific injury pattern?
Correct Answer & Explanation
. LCL repair, MCL repair, radial head fixation/replacement, coronoid fixation
Explanation
The standard surgical sequence for a terrible triad injury (defined as an elbow dislocation with fractures of the radial head and coronoid process) proceeds from deep to superficial. The classic algorithmic approach described by Ring and Jupiter is to first fix or reconstruct the coronoid fracture, followed by radial head fixation or arthroplasty, and finally repair of the lateral collateral ligament (LCL) complex. The medial collateral ligament (MCL) is rarely repaired unless there is gross persistent valgus instability after the lateral and anterior structures are stabilized.
Question 2287
Topic: Shoulder Arthroplasty & Arthritis
In reverse total shoulder arthroplasty (RTSA), which of the following glenosphere configurations has been shown to most effectively minimize the risk of scapular notching?
Correct Answer & Explanation
. Superior tilt and medialization
Explanation
Scapular notching is a well-documented complication in RTSA resulting from mechanical impingement of the humeral component against the inferior scapular neck. Implementing an inferior tilt of the glenosphere along with lateralization increases the clearance between the humeral component and the scapular pillar during adduction, thereby significantly reducing the incidence of scapular notching.
Question 2288
Topic: 9. Shoulder and Elbow
A 45-year-old male presents with a 'terrible triad' injury of the elbow following a fall from a height. After closed reduction, surgical management is indicated due to persistent instability. Which of the following represents the most widely accepted sequence of surgical repair for this injury pattern?
Correct Answer & Explanation
. Lateral collateral ligament (LCL) repair, followed by radial head fixation/replacement, and finally coronoid fixation
Explanation
The standard surgical protocol for a terrible triad injury involves a 'deep-to-superficial' approach working from the inside out. First, the coronoid is addressed (via fixation or anterior capsular repair), followed by the radial head (fixation or arthroplasty), and finally the lateral collateral ligament (LCL) complex is repaired. The medial collateral ligament (MCL) is typically only addressed if the elbow remains unstable after the lateral side has been stabilized.
Question 2289
Topic: Shoulder Arthroplasty & Arthritis
A 72-year-old female undergoes an uncomplicated reverse total shoulder arthroplasty (rTSA) for massive rotator cuff tear arthropathy. Postoperatively, she demonstrates significantly improved forward elevation but exhibits an isolated, severe loss of active external rotation with the arm at the side. Preoperatively, she had a positive hornblower's sign. Deficiency in which of the following muscles is most directly responsible for this specific functional loss following an rTSA?
Correct Answer & Explanation
. Subscapularis
Explanation
In reverse total shoulder arthroplasty, the deltoid is tensioned to provide forward elevation, compensating for the absent supraspinatus. However, the teres minor remains the primary active external rotator with the arm at the side. If the teres minor is absent or non-functional (indicated preoperatively by a positive hornblower's sign or drop sign, and significant fatty infiltration on MRI), the patient will lack active external rotation postoperatively.
Question 2290
Topic: 9. Shoulder and Elbow
A 21-year-old collegiate baseball pitcher reports medial elbow pain during the late cocking phase of throwing. Magnetic resonance arthrography confirms a full-thickness tear of the anterior bundle of the ulnar collateral ligament (UCL). Which of the following biomechanical principles best describes the primary restraint provided by this specific structure?
Correct Answer & Explanation
. It is the primary restraint to valgus stress at 0 to 30 degrees of elbow flexion.
Explanation
The anterior bundle of the ulnar collateral ligament (UCL) is the primary static restraint to valgus stress at the elbow between 30 and 120 degrees of flexion. In full extension (0 to 30 degrees), the bony articulation (olecranon engaging in the olecranon fossa) and the anterior joint capsule provide a significant portion of valgus stability.
Question 2291
Topic: Shoulder Pathology
A 35-year-old female is diagnosed with neurogenic thoracic outlet syndrome characterized by chronic upper extremity paresthesias and weakness exacerbated by overhead activity. She has failed six months of conservative management. Surgical decompression is planned. What is the most widely accepted and definitive surgical intervention for this condition?
Correct Answer & Explanation
. Resection of the clavicle and subclavius muscle
Explanation
Neurogenic thoracic outlet syndrome is most frequently caused by compression of the brachial plexus within the scalene triangle, which is bordered by the anterior scalene, the middle scalene, and the first rib. When surgical intervention is required, decompression classically involves resection of the first rib combined with an anterior scalenectomy (and often a middle scalenectomy) to effectively widen the thoracic outlet and relieve neurovascular compression.
Question 2292
Topic: Shoulder Arthroplasty & Arthritis
Scapular notching is a common complication following reverse total shoulder arthroplasty (RTSA). Which of the following component positioning strategies is most effective in minimizing the risk of inferior scapular notching?
Correct Answer & Explanation
. Superior placement and neutral tilt of the glenosphere
Explanation
Scapular notching is a well-known complication of RTSA, caused by mechanical impingement of the humeral component against the inferior scapular neck during adduction. Placing the glenosphere more inferiorly (overhanging the inferior glenoid bone by 2-4 mm) and with an inferior tilt can help to reduce this mechanical conflict. Lateralizing the center of rotation also decreases notching. Increasing the humeral neck-shaft angle to 155 degrees (more valgus) actually increases the risk of notching compared to an angle of 135 degrees.
Question 2293
Topic: 9. Shoulder and Elbow
The medial ulnar collateral ligament (MUCL) of the elbow consists of anterior, posterior, and transverse bundles. During the late cocking and early acceleration phases of throwing, which specific structure is the primary restraint to valgus stress?
Correct Answer & Explanation
. The transverse bundle of the MUCL
Explanation
The anterior bundle of the MUCL is the primary restraint to valgus stress at the elbow. It is further subdivided into anterior and posterior bands. The anterior band of the anterior bundle is tight in extension and is the primary restraint to valgus stress up to 90 degrees of flexion, which covers the late cocking and early acceleration phases of throwing. The posterior band is tight in flexion (greater than 90 degrees). The radiocapitellar joint acts as a secondary restraint.
Question 2294
Topic: Elbow & Forearm
A 35-year-old male sustains a "terrible triad" injury to his left elbow following a fall from a height. The standard surgical sequence for reconstruction typically involves which of the following steps?
Correct Answer & Explanation
. Medial collateral ligament repair, followed by radial head fixation/replacement, then coronoid fixation, and finally lateral collateral ligament repair.
Explanation
The "terrible triad" of the elbow includes an elbow dislocation, a radial head fracture, and a coronoid process fracture. The classic surgical treatment algorithm, as described by Pugh and McKee, proceeds from deep to superficial and typically from medial to lateral (when approaching from the lateral side). The standard sequence is: 1) Fixation of the coronoid fracture (to restore the anterior buttress), 2) Fixation or replacement of the radial head (to restore the anterior and valgus buttress), 3) Repair of the lateral collateral ligament complex (specifically the LUCL, to restore posterolateral rotatory stability). Repair of the medial collateral ligament (MCL) or application of a hinged external fixator is reserved for cases where the elbow remains unstable after the first three steps are completed.
Question 2295
Topic: 9. Shoulder and Elbow
A 42-year-old male bodybuilder feels a "pop" in his anterior elbow while performing heavy deadlifts. He presents with weakness in forearm supination and elbow flexion. If surgical repair is performed using a two-incision technique rather than a single anterior incision, which of the following complications is more significantly increased?
Correct Answer & Explanation
. Lateral antebrachial cutaneous nerve injury
Explanation
Surgical repair of distal biceps tendon ruptures can be performed via a single anterior incision or a two-incision technique (anterior and posterolateral). The two-incision technique was historically developed to reduce the risk of radial nerve injury associated with the extensile single anterior incision. However, the two-incision technique carries a significantly higher risk of heterotopic ossification and proximal radioulnar synostosis, which can severely limit forearm rotation. Injury to the lateral antebrachial cutaneous nerve (LABCN) is the most common neurologic complication overall, but it is typically associated with the anterior approach. The radial nerve is more at risk with a single anterior incision, particularly if retractors are placed aggressively.
Question 2296
Topic: Elbow & Forearm
A 45-year-old male presents after a fall on an outstretched hand, sustaining a 'terrible triad' injury of the elbow. Which of the following best describes the appropriate surgical sequence and principles to restore joint stability?
Correct Answer & Explanation
. Fix coronoid, replace radial head, repair medial collateral ligament (MCL), then lateral ulnar collateral ligament (LUCL) if still unstable
Explanation
The standard surgical protocol for a terrible triad injury (coronoid fracture, radial head fracture, and elbow dislocation resulting in a LUCL tear) follows an inside-out or deep-to-superficial approach. The sequence typically involves: 1) fixing the coronoid process, 2) fixing or replacing the radial head, and 3) repairing the LUCL to the lateral epicondyle. If the elbow remains unstable after these steps, the MCL is repaired or a hinged external fixator is placed.
Question 2297
Topic: 9. Shoulder and Elbow
A 72-year-old female presents with chronic right shoulder pain and an inability to actively elevate her arm above 60 degrees. Passive range of motion is full. Radiographs show a Hamada Grade 3 arthropathy (acromiohumeral interval < 7mm with acetabularization of the acromion). MRI reveals a massive, retracted, and fatty-infiltrated tear of the supraspinatus and infraspinatus. What is the most reliable surgical option to restore active elevation?
Correct Answer & Explanation
. Arthroscopic rotator cuff repair
Explanation
This patient presents with pseudoparalysis due to a massive, irreparable rotator cuff tear and concurrent rotator cuff arthropathy (Hamada grade 3). Reverse total shoulder arthroplasty (RTSA) is the most reliable treatment to restore forward elevation in this scenario. RTSA medializes and distalizes the center of rotation, recruiting the deltoid to act as the primary elevator. Superior capsular reconstruction and tendon transfers are generally contraindicated in the setting of significant glenohumeral arthritis and established pseudoparalysis.
Question 2298
Topic: Shoulder Pathology
A 28-year-old female overhead athlete complains of numbness and tingling in her medial forearm and hand that worsens with overhead activity. The Adson test is positive, and EMG confirms delayed conduction across the brachial plexus. If the neurovascular compression is occurring in the primary anatomic space implicated in neurogenic thoracic outlet syndrome, what are its boundaries?
Correct Answer & Explanation
. Anterior scalene, middle scalene, and first rib
Explanation
The patient has symptoms of neurogenic thoracic outlet syndrome (nTOS). The most common site of compression in nTOS is the scalene triangle. The borders of the interscalene triangle are the anterior scalene muscle (anterior), the middle scalene muscle (posterior), and the first rib (inferiorly). The brachial plexus roots/trunks and the subclavian artery pass through this interval, whereas the subclavian vein passes anterior to the anterior scalene.
Question 2299
Topic: 9. Shoulder and Elbow
A 22-year-old collegiate baseball pitcher presents with medial elbow pain and decreased pitching velocity. An MRI arthrogram demonstrates a full-thickness tear of the anterior bundle of the ulnar collateral ligament (UCL). During a Tommy John reconstruction, which specific anatomic footprint on the ulna must be restored to ensure normal kinematics and valgus stability?
Correct Answer & Explanation
. Olecranon tip
Explanation
The anterior bundle of the ulnar collateral ligament (UCL) is the primary restraint to valgus stress at the elbow. Its anatomic distal footprint is located on the sublime tubercle, which is situated on the medial aspect of the coronoid process of the ulna. Accurately restoring this footprint during UCL reconstruction is crucial to re-establishing normal elbow kinematics and preventing recurrent valgus instability.
Question 2300
Topic: Shoulder Arthroplasty & Arthritis
A 65-year-old female underwent an anatomic total shoulder arthroplasty (TSA) 6 weeks ago utilizing a standard deltopectoral approach with subscapularis peel and repair. She now complains of increased pain and profound weakness with internal rotation. On examination, she has a positive bear-hug test and increased passive external rotation compared to the contralateral side. What is the most appropriate next step in management?
Correct Answer & Explanation
. Physical therapy focusing on anterior deltoid strengthening
Explanation
The patient's presentation of new-onset internal rotation weakness, a positive bear-hug test, and increased passive external rotation 6 weeks post-TSA is classic for acute subscapularis failure. Early recognition is critical. When diagnosed in the acute or subacute postoperative period, primary revision surgery to repair the subscapularis tendon is indicated to restore function and prevent secondary anterior instability of the prosthesis. If the condition is chronic and the subscapularis is irreparable or the patient has developed anterior escape, conversion to a reverse TSA may be required.
Test Yourself
Switch to an interactive, timed exam simulation to truly master this topic.
