When polyethylene is exposed to radiation and subsequently heated, certain chemical changes occur in the material. Which of the following statements best describes these changes?

The process improves (lowers) the wear rate but may increase the risk of fracture.

Which of the following preoperative findings is a predictor of poor outcome following arthroscopic debridement for glenohumeral arthritis? Review Topic

Nonconcentric joint space on preoperative radiographs

Figures A and B show the six-month follow-up radiographs of a 62-year-old woman who sustained a hip fracture in a fall. Prior to the fall, the patient was active and had no difficulty with ambulation. The patient underwent open reduction and internal

Conversion to total hip arthroplasty with a long cementless stem

A 58-year-old woman with rheumatoid arthritis has progressive neck pain, upper extremity and lower extremity weakness, and difficulty with fine motor movements. Examination reveals hyperreflexia with mild to moderate objective weakness but the patien

Posterior atlanto-dens interval of greater than 14 mm

A 34-year-old man has had a 13-month history of an equinovarus deformity of the foot and ankle after a motorcycle accident. His foot and ankle are flexible, but bracing has become uncomfortable. Active dorsiflexion and eversion are absent. What is th

Posterior tibialis tendon transfer to the lateral midfoot with Achilles tendon lengthening

Shoulder & Elbow EMQs Review by Dr Hutaif Shoul

Question 1

A 22-year-old rugby player presents with recurrent anterior shoulder instability. An MRI shows an engaging Hill-Sachs lesion. According to the glenoid track concept, which of the following best describes the criteria for an 'off-track' Hill-Sachs lesion?

Explanation

According to the glenoid track concept described by Di Giacomo et al., if the Hill-Sachs interval (HSI) - defined as the width of the Hill-Sachs lesion plus the intact anterior bone bridge - is greater than the glenoid track width (which is 83% of the intact glenoid width minus any anterior bone loss), the lesion will engage the anterior glenoid rim. This is termed an 'off-track' lesion.

Question 2

In the biomechanical design of a Grammont-style reverse total shoulder arthroplasty (RTSA), how is the center of rotation (COR) altered compared to a native anatomic shoulder?

Explanation

The Grammont-style RTSA medializes and distalizes the center of rotation. Medialization increases the deltoid lever arm and decreases torque on the glenoid component, while distalization tensions the deltoid, improving its efficiency for forward elevation in the absence of a functional rotator cuff.

Question 3

A 65-year-old man undergoes revision shoulder arthroplasty for presumed aseptic loosening. Intraoperative cultures subsequently grow Cutibacterium acnes (formerly Propionibacterium acnes). Which of the following best describes the microbiological profile of this organism?

Explanation

Cutibacterium acnes is a Gram-positive, anaerobic (or microaerophilic), non-spore-forming pleomorphic bacillus. It is a slow-growing commensal organism commonly found in the sebaceous glands of the shoulder and is a leading cause of indolent periprosthetic joint infections following shoulder arthroplasty.

Question 4

A 40-year-old woman falls on an outstretched hand and sustains a 'terrible triad' injury of the elbow. During surgical reconstruction, what is the most widely accepted sequence of repair to restore elbow stability?

Explanation

The standard surgical algorithm for a terrible triad injury of the elbow is to build from 'deep to superficial' or 'inside out'. This typically involves: 1) Fixation of the coronoid fracture, 2) Fixation or replacement of the radial head, and 3) Repair of the lateral collateral ligament (LCL) complex. The MCL is only repaired if the elbow remains unstable after these steps.

Question 5

A patient with a history of recurrent elbow giving way describes a clicking sensation when pushing out of a chair. Examination reveals a positive lateral pivot-shift test. This condition is most directly caused by incompetence of which of the following structures?

Explanation

The patient's presentation is classic for posterolateral rotatory instability (PLRI) of the elbow. The primary pathoanatomy of PLRI is a deficiency or avulsion of the lateral ulnar collateral ligament (LUCL), which normally acts as a crucial restraint against posterolateral subluxation of the radial head.

Question 6

A 52-year-old recreational tennis player presents with persistent anterior shoulder pain and mechanical symptoms. An MRI arthrogram confirms an isolated Type II SLAP tear. After failed conservative management, what is the most appropriate surgical intervention for this patient?

Explanation

In older or middle-aged patients (typically >40-45 years), particularly those who are not elite overhead athletes, biceps tenodesis provides more predictable pain relief and functional improvement with fewer complications (like postoperative stiffness) compared to a formal Type II SLAP repair.

Question 7

A 28-year-old male sustains blunt trauma to his right posterolateral neck and shoulder. He subsequently presents with medial winging of his scapula, which worsens when he pushes against a wall. Which nerve is most likely injured, and what is its segmental origin?

Explanation

Medial scapular winging is caused by paralysis of the serratus anterior muscle, which is innervated by the long thoracic nerve. The long thoracic nerve arises from the ventral rami of the C5, C6, and C7 nerve roots.

Question 8

A 50-year-old patient with an irreparable posterosuperior rotator cuff tear requires a tendon transfer to restore external rotation. Which of the following tendon transfers provides a line of pull that most closely replicates the native infraspinatus muscle vector?

Explanation

The lower trapezius transfer (typically using an Achilles or hamstring tendon allograft for length) has a line of pull that very closely matches the native vector of the infraspinatus, making it biomechanically superior to the latissimus dorsi for primarily restoring external rotation in massive posterosuperior cuff tears.

Question 9

A surgeon performs a primary distal biceps tendon repair utilizing a single-incision anterior approach. Postoperatively, the patient reports numbness and tingling along the radial aspect of the forearm. Which nerve is most likely injured?

Explanation

The lateral antebrachial cutaneous nerve (LABC) is the most commonly injured nerve during a single-incision anterior approach to the distal biceps. It courses just lateral to the biceps tendon in the subcutaneous tissue. The PIN is more at risk during a two-incision approach or if retractors are placed too deeply on the radial neck.

Question 10

During surgical decompression of the ulnar nerve for cubital tunnel syndrome, a tight fascial band spanning between the olecranon and the medial epicondyle is identified overlying the two heads of the flexor carpi ulnaris (FCU). What is the anatomical name of this structure?

Explanation

Osborne's ligament (or the cubital tunnel retinaculum) forms the roof of the cubital tunnel, bridging the olecranon and medial epicondyle over the two heads of the FCU. The Arcade of Struthers is a fascial band approximately 8 cm proximal to the medial epicondyle. The Ligament of Struthers is associated with the median nerve and a supracondylar process.

Question 11

Current anatomical studies evaluating the vascular supply to the proximal humerus demonstrate that the principal blood supply to the humeral head is derived primarily from which of the following vessels?

Explanation

Historically, the anterior humeral circumflex artery (via its anterolateral ascending branch, the arcuate artery) was thought to be the main blood supply. However, more recent quantitative anatomical studies (e.g., Brooks et al., and Hettrich et al.) have demonstrated that the posterior humeral circumflex artery actually provides the majority (up to 64%) of the blood supply to the humeral head.

Question 12

The Dubberley classification is used to describe coronal shear fractures of the distal humerus. What does the 'B' modifier in this classification system indicate?

Explanation

In the Dubberley classification for coronal shear fractures (capitellum/trochlea), Type 1 is a capitellar fracture, Type 2 includes the capitellum and lateral trochlea in one piece, and Type 3 features the capitellum and lateral trochlea as separate fragments. The modifiers 'A' and 'B' denote the absence or presence of posterior condylar comminution, respectively. The 'B' modifier often dictates the need for a posterior approach with an olecranon osteotomy.

Question 13

A 29-year-old male volleyball player presents with isolated weakness in external rotation of the right shoulder. Forward elevation strength is 5/5. MRI reveals a paralabral cyst. At which anatomical location is the cyst most likely compressing the suprascapular nerve?

Explanation

The suprascapular nerve innervates the supraspinatus muscle and then passes through the spinoglenoid notch to innervate the infraspinatus. Entrapment at the spinoglenoid notch (commonly by a paralabral cyst associated with a posterior labral tear) causes isolated infraspinatus weakness (external rotation deficit). Entrapment at the suprascapular notch would affect both the supraspinatus and infraspinatus.

Question 14

During a coracoclavicular (CC) ligament reconstruction for a chronic Type V acromioclavicular joint separation, the surgeon must replicate the native anatomy of the conoid and trapezoid ligaments. Which of the following best describes the anatomical orientation of the conoid ligament insertion on the clavicle relative to the trapezoid ligament?

Explanation

The coracoclavicular (CC) ligaments consist of the conoid and trapezoid. The conoid ligament is positioned medial and posterior to the trapezoid ligament. It inserts on the conoid tubercle of the posterior-inferior clavicle, while the trapezoid inserts anterolaterally on the trapezoid line.

Question 15

A 13-year-old elite baseball pitcher presents with insidious onset of shoulder pain during the late cocking phase of throwing. Radiographs demonstrate widening and lateral fragmentation of the proximal humeral physis. What is the most appropriate initial management?

Explanation

The patient has 'Little League Shoulder', which is a proximal humeral epiphysiolysis caused by repetitive rotational stress on the open physis during throwing. The standard of care is non-operative, primarily consisting of complete rest from throwing for 2 to 3 months, followed by physical therapy focusing on core/scapular mechanics, and finally a graduated return-to-throwing program.

Question 16

A 32-year-old bodybuilder experiences a sharp pop and sudden pain in his anterior chest wall while performing a heavy bench press. He is diagnosed with a complete pectoralis major rupture. Regarding the normal anatomy of the pectoralis major tendon insertion on the humerus, which of the following statements is true?

Explanation

The pectoralis major tendon has a unique twisted insertion on the lateral lip of the bicipital groove. The clavicular head inserts anteriorly (superficial) and distally. The sternocostal head twists upon itself so that its most inferior fibers insert superiorly, resulting in the sternocostal head inserting deep and proximal to the clavicular head. It is the sternocostal head that is most commonly ruptured during a bench press.

Question 17

A 55-year-old diabetic woman presents with stage II 'freezing' adhesive capsulitis of the shoulder. Histological evaluation of the joint capsule in this condition typically reveals dense fibroblastic proliferation. Which specific anatomical structures are primarily contracted and thickened early in the pathogenesis of this disease?

Explanation

The primary site of pathology in early idiopathic adhesive capsulitis is the rotator interval, which contains the coracohumeral ligament (CHL) and the superior glenohumeral ligament (SGHL). Contracture of these structures, particularly the CHL, heavily restricts external rotation, which is the hallmark clinical finding in frozen shoulder.

Question 18

In the surgical management of recalcitrant lateral epicondylitis (tennis elbow), debridement is primarily targeted at the macroscopic degenerative tissue (angiofibroblastic hyperplasia) found within the origin of which muscle?

Explanation

Lateral epicondylitis is characterized by angiofibroblastic tendinosis primarily involving the origin of the extensor carpi radialis brevis (ECRB). During surgical release/debridement, the ECRB origin is located deep to the extensor digitorum communis (EDC) aponeurosis at the lateral epicondyle.

Question 19

In the throwing athlete, the medial ulnar collateral ligament (UCL) of the elbow is subjected to significant stress. Which specific bundle of the UCL provides the primary restraint to valgus stress at 90 degrees of elbow flexion?

Explanation

The anterior bundle of the medial ulnar collateral ligament (UCL) is the primary restraint to valgus instability of the elbow from 30 to 120 degrees of flexion. The posterior bundle is a secondary restraint, taut in flexion >90 degrees, and the transverse ligament (Cooper's) has no significant role in elbow stability.

Question 20

A 19-year-old male is brought to the trauma bay after a high-speed motor vehicle collision. He has dyspnea, dysphagia, and an obvious depression at the medial aspect of his right clavicle. A CT scan confirms a posterior sternoclavicular dislocation. What is the most appropriate next step in management?

Explanation

Posterior sternoclavicular dislocations are orthopedic emergencies due to the proximity of the great vessels, trachea, and esophagus. Up to 30% are associated with intrathoracic injury. The standard of care is urgent closed reduction under general anesthesia in the operating room, with a cardiothoracic surgeon present or on immediate standby in case of a catastrophic vascular injury during reduction.

Question 21

A 35-year-old male presents with elbow trauma after a fall. Computed tomography shows a fracture of the anteromedial facet of the coronoid process. What is the primary mechanism of injury, and what is the recommended surgical approach for fixation if required?

Explanation

Anteromedial facet fractures of the coronoid occur due to a varus posteromedial rotatory instability (VPMRI) mechanism. The lateral collateral ligament (LCL) is typically avulsed from the lateral epicondyle, and the anteromedial coronoid facet is sheared off. Fixation is usually required to restore stability, specifically via a medial-based approach (such as a flexor carpi ulnaris split or Hotchkiss over-the-top approach) combined with lateral LCL repair.

Question 22

In the design of a semi-constrained (linked) total elbow arthroplasty, the 'sloppy hinge' (a degree of toggle between the components) is incorporated primarily to accomplish which of the following?

Explanation

Early rigid hinge elbow arthroplasties failed at high rates due to aseptic loosening caused by transmission of rotational and varus/valgus forces directly to the implant-cement-bone interface. Modern linked (semi-constrained) implants utilize a 'sloppy hinge' with several degrees of toggle. This design intentionally dissipates these forces at the articulation rather than at the stem interfaces, dramatically reducing the rate of aseptic loosening.

Question 23

A 42-year-old recreational weightlifter undergoes an anterior single-incision approach for a distal biceps tendon repair. Which of the following is the most common neurologic complication specifically associated with this surgical approach?

Explanation

The lateral antebrachial cutaneous nerve (LABCN) is the most frequently injured nerve during a single-incision anterior approach to the distal biceps, due to its proximity to the cephalic vein and the superficial dissection plane. Posterior interosseous nerve (PIN) injury is also a severe risk if retractors are placed too deeply or blindly on the radial neck, but LABCN neuropraxia is significantly more common.

Question 24

To minimize the risk of inferior scapular notching in a reverse total shoulder arthroplasty (RTSA), the glenosphere baseplate should ideally be positioned with which of the following orientations?

Explanation

Scapular notching is a well-documented complication of RTSA, caused by mechanical impingement of the humeral polyethylene insert against the inferior scapular neck during adduction. To minimize this, the glenosphere baseplate should be placed as inferiorly as possible on the glenoid, usually flush with or slightly overhanging the inferior rim, and with a neutral to slightly inferior tilt.

Question 25

A 45-year-old bodybuilder feels a 'pop' in his posterior distal arm while performing heavy bench presses. MRI confirms a complete triceps tendon rupture. During surgical repair, an anatomical understanding of the triceps footprint is essential. The normal triceps insertion is best described as:

Explanation

The triceps tendon does not insert merely on the tip of the olecranon. Its anatomic footprint is broad, dome-shaped, and covers a wide area on the posterior-proximal olecranon. Restoring this broad footprint during repair (often using transosseous-equivalent double-row or strong single-row techniques) is important to recreate normal biomechanical pull and strength.

Question 26

A 24-year-old rugby player has recurrent anterior shoulder instability. CT evaluation demonstrates an engaging Hill-Sachs lesion ('off-track') with 10% anterior glenoid bone loss. What is the most appropriate surgical management?

Explanation

In the setting of recurrent anterior instability with 'subcritical' glenoid bone loss (typically <15-20%) but an off-track (engaging) Hill-Sachs lesion, arthroscopic Bankart repair combined with a Remplissage procedure (infraspinatus tenodesis and capsulodesis into the defect) effectively converts the lesion to 'on-track' and prevents engagement. Latarjet is generally reserved for critical bone loss (>20%).

Question 27

A 28-year-old volleyball player presents with painless weakness of her dominant shoulder. Physical examination reveals isolated atrophy of the infraspinatus with normal supraspinatus bulk and strength. Where is the most likely site of nerve compression?

Explanation

The suprascapular nerve innervates both the supraspinatus and infraspinatus muscles. Compression at the suprascapular notch affects both muscles. However, as the nerve traverses the spinoglenoid notch, it innervates only the infraspinatus. Therefore, a lesion at the spinoglenoid notch (commonly a paralabral cyst associated with a posterior labral tear) results in isolated infraspinatus atrophy and weakness.

Question 28

A 40-year-old female sustains a coronal shear fracture of the capitellum and lateral trochlea. CT scan reveals extensive posterior comminution of the lateral condyle. According to the Dubberley classification, what is the surgical implication of this posterior comminution?

Explanation

The Dubberley classification of capitellum fractures distinguishes between Type A (no posterior comminution) and Type B (posterior comminution). Type B fractures lack a stable posterior buttress. Therefore, anterior-to-posterior headless compression screws alone will fail due to lack of posterior support. These require a posterior buttress plate to prevent displacement.

Question 29

A 32-year-old male tears his pectoralis major while performing a maximal bench press. Which of the following represents the typical sequence of tearing of the pectoralis major tendon at its humeral insertion?

Explanation

The sternal head of the pectoralis major inserts deep and proximal to the clavicular head. During a bench press (specifically at the lowest point of the lift when the arm is extended, abducted, and externally rotated), the sternal head is placed under maximum tension and is predictably the first part of the tendon to rupture, followed by the clavicular head if the force continues.

Question 30

A 12-year-old male baseball pitcher presents with medial elbow pain and decreased pitching velocity. Radiographs reveal widening of the medial epicondyle apophysis. The pathophysiology of this condition (Little League Elbow) is best characterized by which biomechanical pattern during the late cocking and early acceleration phases of throwing?

Explanation

The throwing motion places severe valgus stress on the elbow. In skeletally immature athletes, this valgus overload causes excessive tension forces on the medial elbow structures (leading to medial epicondyle apophysitis or avulsion) and excessive compression forces on the lateral elbow structures (which can lead to osteochondritis dissecans of the capitellum).

Question 31

A 45-year-old male sustains a 'terrible triad' injury of the elbow (dislocation, radial head fracture, and coronoid fracture) requiring operative fixation. What is the classic, biomechanically recommended sequence of surgical reconstruction for this injury complex?

Explanation

The standard surgical algorithm for a terrible triad injury involves an inside-out approach: 1) Fixation of the coronoid process (to restore the anterior buttress), 2) Fixation or replacement of the radial head (to restore the anterior and lateral column), and 3) Repair of the lateral collateral ligament (LCL) complex to the lateral epicondyle. The MCL is only repaired if gross instability remains after these steps.

Question 32

A 55-year-old manual laborer with an irreparable posterosuperior rotator cuff tear is evaluated for a latissimus dorsi tendon transfer. He has intact forward elevation to 100 degrees but persistent pain and severe external rotation weakness. Which of the following preoperative findings is a recognized contraindication to a successful latissimus dorsi transfer?

Explanation

A successful latissimus dorsi transfer for a massive posterosuperior cuff tear relies on an intact force couple in the transverse plane. An irreparable subscapularis tear compromises the anterior aspect of this force couple, making a latissimus dorsi transfer functionally ineffective and historically a strict contraindication. Advanced age, deltoid deficiency, and pseudoparalysis are also contraindications.

Question 33

A 19-year-old football player sustains a high-energy blow to the medial clavicle. He presents in the trauma bay with shortness of breath, venous engorgement of the ipsilateral arm, and dysphagia. What is the most critical initial step in the management of this patient?

Explanation

This patient has a posterior sternoclavicular (SC) joint dislocation with signs of mediastinal compression (dyspnea, venous engorgement, dysphagia). This is a surgical emergency. The standard of care mandates obtaining a CT scan to define the exact relationship of the clavicle to the great vessels and trachea, and cardiothoracic surgery must be on standby during reduction due to the high risk of catastrophic vascular injury during manipulation.

Question 34

A 50-year-old diabetic female presents with globally restricted active and passive shoulder range of motion. Arthroscopic evaluation reveals dense, mature collagenous adhesions in the rotator interval and a thickened coracohumeral ligament, but minimal active synovitis. This presentation is consistent with the 'frozen' stage of adhesive capsulitis. Which cytokine is most strongly associated with the profibrotic cascade in this condition?

Explanation

Adhesive capsulitis is characterized by an initial inflammatory phase followed by a dense fibrotic phase. Transforming Growth Factor-beta (TGF-b) and Platelet-Derived Growth Factor (PDGF) are the primary profibrotic cytokines responsible for fibroblast proliferation and collagen deposition in the joint capsule and rotator interval, distinguishing the 'frozen' stage (Stage III) from the earlier, highly vascular 'freezing' stage (Stage II).

Question 35

During shoulder arthroscopy for recurrent anterior instability in a 25-year-old athlete, the surgeon notes an intact labrum but an avulsion of the inferior glenohumeral ligament from the anatomic neck of the humerus. Which associated injury has a notable incidence with this specific lesion?

Explanation

The scenario describes a HAGL (Humeral Avulsion of the Glenohumeral Ligament) lesion. HAGL lesions are an important cause of recurrent instability in patients without a Bankart lesion. They have a known and notable association with subscapularis tendon tears (often occurring concomitantly during the traumatic event), and the subscapularis must be carefully evaluated.

Question 36

A 34-year-old male sustains a closed, highly comminuted olecranon fracture that extends distally past the level of the coronoid process. What is the preferred method of internal fixation to minimize the risk of hardware failure and maximize stability?

Explanation

Tension band wiring relies on the anterior cortex acting as a buttress to convert tension forces into compression at the articular surface. In comminuted olecranon fractures, or those extending distal to the coronoid process, the anterior buttress is deficient. Tension band wiring in this setting will lead to collapse, shortening, and failure. A posterior pre-contoured locking plate is the treatment of choice to span the comminution and provide rigid stability.

Question 37

A 22-year-old collegiate baseball pitcher undergoes medial ulnar collateral ligament (MUCL) reconstruction using a palmaris longus autograft via the modified Jobe (figure-of-eight) technique. Postoperatively, what is the most frequently reported complication specific to this procedure?

Explanation

Ulnar neuropathy is the most common complication following medial ulnar collateral ligament (MUCL) reconstruction (Tommy John surgery). It can occur due to traction, compression during exposure, or issues related to ulnar nerve transposition (if performed). While modern techniques (like the docking technique) have reduced this rate by minimizing nerve handling, it remains the leading complication.

Question 38

During normal human shoulder elevation from 30 degrees to 150 degrees, normal kinematics dictate a coordinated movement between the glenohumeral joint and the scapulothoracic articulation. What is the generally accepted overall ratio of glenohumeral to scapulothoracic motion (scapulohumeral rhythm)?

Explanation

The classic 'scapulohumeral rhythm' described by Inman et al. dictates a 2:1 ratio of glenohumeral joint motion to scapulothoracic motion during active arm elevation. For every 3 degrees of total shoulder elevation, 2 degrees occur at the glenohumeral joint and 1 degree occurs at the scapulothoracic articulation.

Question 39

A 40-year-old carpenter presents with numbness in his small finger and the ulnar half of the ring finger. During an in situ decompression for cubital tunnel syndrome, the surgeon releases a thick fascial band spanning between the olecranon and the medial epicondyle (connecting the two heads of the flexor carpi ulnaris). What is the eponym for this specific structure?

Explanation

Osborne's ligament (or the arcuate ligament) forms the roof of the cubital tunnel. It is a fibrous band connecting the humeral and ulnar heads of the flexor carpi ulnaris (FCU), spanning from the medial epicondyle to the olecranon. Release of this structure is the key step in surgical decompression of the ulnar nerve at the elbow. The Arcade of Struthers is a different potential compression site located 8-10 cm proximal to the medial epicondyle.

Question 40

A 68-year-old male with primary glenohumeral osteoarthritis is evaluated for shoulder arthroplasty. Axillary radiographs and CT imaging reveal a biconcave glenoid with 25 degrees of posterior retroversion and significant posterior subluxation of the humeral head (Walch B2 glenoid). What is the most reliable surgical option to prevent early component failure in this older patient?

Explanation

Managing a severe Walch B2 glenoid (high retroversion >15-20 degrees and significant posterior subluxation) with a standard anatomic total shoulder arthroplasty (TSA) is fraught with high failure rates. Asymmetric reaming to correct 25 degrees of retroversion would remove too much subchondral bone, violating the glenoid vault. In an older patient, Reverse Total Shoulder Arthroplasty (RTSA) provides much more reliable stability, corrects the subluxation, and has excellent long-term survivorship compared to standard anatomic TSA in this setting.

Question 41

A 35-year-old male presents with recurrent catching and clicking in his right elbow, particularly when pushing himself up from a seated position. Physical examination reveals apprehension with axial compression, supination, and valgus stress applied to the elbow during flexion. Which of the following structures is most likely deficient?

Explanation

The clinical scenario and provocative maneuver (lateral pivot-shift test of the elbow) are classic for Posterolateral Rotatory Instability (PLRI). PLRI is the most common pattern of chronic elbow instability and is caused by an insufficiency of the lateral ulnar collateral ligament (LUCL). The LUCL serves as the primary restraint to posterolateral rotatory forces. It originates on the lateral epicondyle and inserts on the supinator crest of the ulna.

Question 42

In the surgical management of a 'terrible triad' injury of the elbow (elbow dislocation, radial head fracture, and coronoid fracture), standard surgical principles dictate a specific sequence of repair. Which of the following represents the most widely accepted sequence of structural reconstruction?

Explanation

The standard surgical algorithm for a terrible triad injury generally progresses from deep to superficial and from anterior to posterior if performed through a single lateral approach, though modern techniques often utilize a dual incision. The accepted structural sequence is to establish the anterior buttress first by repairing or fixing the coronoid, followed by restoring the radiocapitellar contact via radial head fixation or arthroplasty, and finally restoring lateral stability by repairing the LUCL. Medial collateral ligament repair or hinged external fixation is reserved for residual instability.

Question 43

A 12-year-old gymnast sustains a medial epicondyle fracture of the humerus. Which of the following is considered an absolute indication for open reduction and internal fixation in this patient?

Explanation

Absolute indications for operative intervention in pediatric medial epicondyle fractures include incarceration of the fragment within the joint space and an open fracture. Relative indications include significant displacement (traditionally >5mm, though controversial), ulnar neuropathy, and valgus instability, particularly in high-level throwing athletes or gymnasts who require absolute stability.

Question 44

A 14-year-old female gymnast presents with chronic, dull lateral elbow pain and catching. Radiographs demonstrate a radiolucent lesion in the capitellum. MRI confirms a 12 mm osteochondral defect with a detached, loose fragment and underlying sclerotic subchondral bone. What is the most appropriate definitive management?

Explanation

The patient has Osteochondritis Dissecans (OCD) of the capitellum, typically seen in adolescent athletes with repetitive compressive forces (gymnasts, pitchers). Because the MRI demonstrates a detached fragment and underlying sclerotic bone, the lesion is unstable and unlikely to heal with in situ fixation. For unstable lesions without a salvable bone fragment (sclerotic base), the standard of care is fragment excision and marrow stimulation (microfracture) to encourage fibrocartilage fill. OATS is typically reserved for large, uncontained defects or failures of primary microfracture.

Question 45

Scapulothoracic dissociation is a high-energy injury characterized by complete disruption of the scapulothoracic articulation. Which of the following associated injuries dictates the functional prognosis of the upper extremity in these patients?

Explanation

Scapulothoracic dissociation involves severe lateral displacement of the scapula, often accompanied by clavicle fractures or AC/SC joint disruptions. The most devastating and prognosis-dictating complication is a traction injury to the brachial plexus, which occurs in the vast majority of cases. Complete brachial plexus avulsions are common and often lead to a flail limb, sometimes necessitating early amputation despite vascular repairs.

Question 46

A 20-year-old rugby player presents with acute dyspnea, dysphagia, and severe pain over the medial clavicle after falling directly onto the posterolateral aspect of his shoulder. Clinical examination suggests a posterior sternoclavicular (SC) joint dislocation. What is the most appropriate imaging modality to confirm the diagnosis and assess associated injuries?

Explanation

Posterior sternoclavicular dislocations are orthopedic emergencies due to the proximity of the great vessels, trachea, and esophagus to the medial clavicle. While a serendipity radiograph can suggest the diagnosis, a CT scan of the chest with intravenous contrast is the gold standard. It precisely delineates the bony displacement and evaluates for compression or injury to the critical retrosternal structures.

Question 47

A 'floating shoulder' results from ipsilateral fractures of the clavicle and the scapular neck, causing a double disruption of the superior shoulder suspensory complex. Which of the following isolated radiographic findings represents the strongest indication for operative intervention?

Explanation

The superior shoulder suspensory complex (SSSC) is a bony/soft tissue ring. A double disruption (floating shoulder) was historically thought to be an absolute surgical indication. However, modern evidence suggests many do well with nonoperative management unless there is severe displacement. Operative fixation is strongly indicated when there is significant translation (medialization of the glenoid >10-20 mm) or severe angulation (>40 degrees) of the scapular neck, which alters the glenohumeral biomechanics and rotator cuff tension.

Question 48

When performing a 2-incision (modified Boyd-Anderson) approach for a distal biceps tendon rupture repair, which of the following complications occurs at a significantly higher rate compared to the single-incision anterior approach?

Explanation

The 2-incision technique for distal biceps repair was developed to avoid the radial/posterior interosseous nerve injuries associated with extensive anterior dissection. However, due to the dissection between the radius and ulna and the creation of a bone tunnel from a separate posterior approach, the rate of heterotopic ossification and resultant radioulnar synostosis is higher than in the single-incision anterior approach. LABCN injury is the most common complication of the single-incision approach.

Question 49

A 45-year-old male with chronic renal failure on hemodialysis presents with severe localized pain above the posterior elbow after lifting a heavy box. He is unable to actively extend his elbow against gravity. A lateral radiograph reveals a 'flake sign.' What is the pathognomonic mechanism of the anatomic injury suggested by this sign?

Explanation

The 'flake sign' on a lateral elbow radiograph refers to a small avulsed cortical bone fragment from the tip of the olecranon. In the setting of loss of active elbow extension, this is pathognomonic for a triceps tendon avulsion. Risk factors for spontaneous tendon ruptures include chronic kidney disease/secondary hyperparathyroidism, anabolic steroid use, and local corticosteroid injections.

Question 50

A 28-year-old competitive weightlifter presents with medial elbow pain and parasthesias in the ring and small fingers. He describes feeling two distinct 'snaps' at the posteromedial elbow when moving from flexion to extension under load. The first snap corresponds to the ulnar nerve dislocating over the medial epicondyle. What anatomical structure is responsible for the second snap?

Explanation

Snapping triceps syndrome involves the sequential dislocation of the ulnar nerve and the medial head of the triceps over the medial epicondyle during elbow flexion, creating two distinct palpable and audible snaps. Hypertrophy of the medial head of the triceps in weightlifters is a common predisposing factor. Management often requires surgical transposition of the ulnar nerve and excision of the subluxating portion of the medial triceps head.

Question 51

A 22-year-old collegiate baseball pitcher complains of posterior elbow pain that is worse during the deceleration phase of throwing. Examination reveals a 15-degree flexion contracture and point tenderness over the posteromedial olecranon. If a conservative program fails, what is the best initial surgical intervention?

Explanation

This patient has valgus extension overload (Pitcher's elbow), which results from repetitive valgus stress and extreme extension during the deceleration phase of throwing. This leads to posteromedial impingement and the formation of a posteromedial olecranon osteophyte. The appropriate surgical treatment is excision of the osteophyte. Care must be taken not to resect too much olecranon (typically limiting resection to <3 mm), as over-resection dramatically increases the strain on the anterior bundle of the MUCL, potentially causing iatrogenic valgus instability.

Question 52

The medial ulnar collateral ligament (MUCL) of the elbow consists of three main bundles. Which specific bundle is considered the primary restraint to valgus stress from 30 to 120 degrees of elbow flexion?

Explanation

The MUCL complex has an anterior bundle, a posterior bundle, and a transverse bundle. The anterior bundle is the primary restraint to valgus stress throughout the functional arc of motion (30 to 120 degrees of flexion). It is the structure most commonly injured in overhead throwing athletes and is the target of 'Tommy John' reconstruction. The posterior bundle is a secondary restraint, most active at higher degrees of flexion, while the transverse bundle does not cross the joint line and provides no significant stability.

Question 53

A 25-year-old minor league pitcher is evaluated for a decline in throwing velocity and vague shoulder pain. Range of motion testing reveals 30 degrees of internal rotation and 120 degrees of external rotation in his throwing shoulder, compared to 60 degrees of internal rotation and 90 degrees of external rotation in his non-throwing shoulder. What is the most appropriate initial management for this condition?

Explanation

The patient demonstrates Glenohumeral Internal Rotation Deficit (GIRD). The definition of pathologic GIRD is a loss of internal rotation (IR) that exceeds the gain in external rotation (ER), leading to an overall loss of total arc of motion compared to the contralateral side. In this case, the throwing shoulder has a total arc of 150 (30+120) compared to the normal 150 (60+90), which represents a symmetric shift in the arc of motion (adaptive GIRD), rather than pathologic. However, regardless of whether it is adaptive or early pathologic GIRD, the initial treatment is always conservative, centered on a posterior capsular stretching program ('sleeper stretches') to address the acquired posterior capsular contracture.

Question 54

A 55-year-old patient presents with acute anterior shoulder pain and weakness after a fall on an outstretched hand. On examination, the patient has a positive belly-press test and a positive bear-hug test. The 'lift-off' test cannot be performed due to restricted internal rotation. These examination findings indicate a tear of which structure?

Explanation

The belly-press, bear-hug, and lift-off tests are all specific physical examination maneuvers designed to evaluate the integrity of the subscapularis tendon. The subscapularis is the primary internal rotator of the shoulder. The belly-press and bear-hug tests are particularly useful when the lift-off test cannot be performed because the patient lacks the necessary passive internal rotation to place their hand behind their lower back.

Question 55

A 32-year-old male presents with severe pain and a cosmetic deformity in his anterior axillary fold after attempting a heavy 1-rep maximum bench press. An MRI confirms a complete rupture of the pectoralis major tendon. What is the most common anatomical site of rupture for the pectoralis major in this demographic?

Explanation

Pectoralis major ruptures occur most frequently in weightlifters (particularly during the bench press) when the muscle is maximally contracted in an eccentric, stretched position (shoulder extension and external rotation). The most common site of rupture is a direct avulsion from its insertion on the lateral lip of the bicipital groove of the humerus. Due to the significant functional and cosmetic deficits, surgical repair is typically indicated in young, active patients.

Question 56

A 40-year-old female presents with vague shoulder pain, weakness in overhead activities, and a visible deformity of the back 3 months after a lymph node biopsy in the posterior triangle of the neck. Physical examination demonstrates lateral winging of the scapula, which worsens with resisted shoulder abduction. Which muscle is paralyzed?

Explanation

Lateral winging of the scapula is caused by paralysis of the trapezius muscle, which is innervated by the spinal accessory nerve (cranial nerve XI). This nerve is highly susceptible to iatrogenic injury during procedures in the posterior cervical triangle (e.g., lymph node biopsy). In contrast, medial winging of the scapula is caused by paralysis of the serratus anterior muscle secondary to a long thoracic nerve injury, typically observed when the patient pushes against a wall.

Question 57

A 68-year-old female is evaluated for severe right elbow pain. Radiographs show advanced post-traumatic arthritis with severe metaphyseal bone loss in both the distal humerus and proximal ulna, as well as gross ligamentous instability. Unlinked (resurfacing) total elbow arthroplasty (TEA) is considered. Which of the following is an absolute contraindication to an unlinked TEA in this patient?

Explanation

Total elbow arthroplasties are generally classified as linked (semi-constrained) or unlinked (resurfacing). Unlinked implants rely completely on the integrity of the collateral ligaments and the surrounding bony architecture for stability. Therefore, profound ligamentous insufficiency and severe metaphyseal bone loss are absolute contraindications to unlinked TEA. In such cases, a linked (semi-constrained) prosthesis is required to prevent dislocation.

Question 58

During the surgical management of a severely comminuted radial head fracture, the radial head is deemed unsalvageable and is excised without replacement. Three months postoperatively, the patient returns with progressive ulnar-sided wrist pain, grip weakness, and proximal migration of the radius seen on radiographs. Injury to which anatomic structure was most likely missed initially?

Explanation

The clinical presentation describes an Essex-Lopresti lesion, which involves a highly comminuted radial head fracture accompanied by a longitudinal disruption of the interosseous membrane (IOM) and the distal radioulnar joint (DRUJ). The radial head and the central band of the IOM are the primary stabilizers against proximal migration of the radius. If the radial head is excised in the presence of an IOM rupture, the radius migrates proximally, leading to severe positive ulnar variance, DRUJ incongruity, and ulnar impaction syndrome. Radial head replacement is strictly indicated to prevent this.

Question 59

A 45-year-old male falls onto an outstretched hand and sustains a coronal shear fracture of the distal humerus. A CT scan reveals a fracture that completely separates the capitellum and the majority of the lateral trochlea from the distal humerus as a single articular piece. According to the Bryan and Morrey classification modified by McKee, how is this fracture classified?

Explanation

The Bryan and Morrey classification describes capitellum fractures. Type I (Hahn-Steinthal) is a large osseous piece of the capitellum. Type II (Kocher-Lorenz) is a thin shell of articular cartilage with minimal subchondral bone. Type III (Broberg-Morrey) is a severely comminuted capitellum fracture. McKee modified the classification by adding Type IV, which is a coronal shear fracture that involves the capitellum and extends medially to include most or all of the trochlea. It often exhibits a double-arc sign on the lateral radiograph.

Question 60

A 45-year-old male presents with a 2-week history of severe, unremitting, burning right shoulder pain that woke him from sleep. The pain has recently subsided, but he now has profound weakness in overhead elevation and external rotation. He reports no preceding trauma. An MRI of the shoulder is unremarkable without evidence of rotator cuff tearing. EMG performed 4 weeks later shows acute denervation potentials isolated to the supraspinatus and infraspinatus muscles. What is the most likely diagnosis?

Explanation

Parsonage-Turner syndrome (acute brachial neuritis or neuralgic amyotrophy) is characterized by the sudden onset of severe, unremitting pain about the shoulder girdle (often waking the patient at night), followed by patchy muscle weakness and atrophy as the pain begins to subside. The suprascapular nerve (innervating the supraspinatus and infraspinatus) is commonly involved, mimicking a massive rotator cuff tear. The absence of trauma, normal shoulder MRI, and EMG findings confirm a neurogenic etiology. Suprascapular nerve entrapment at the spinoglenoid notch would typically present with isolated infraspinatus involvement without the antecedent severe, acute pain phase.

Question 61

A 35-year-old falls on an outstretched hand, sustaining a varus posteromedial rotatory instability (PMRI) injury of the elbow. Imaging shows a fracture of the anteromedial facet of the coronoid process. What ligamentous injury is most predictably associated with this specific fracture pattern?

Explanation

Fractures of the anteromedial facet of the coronoid are the hallmark of posteromedial rotatory instability (PMRI) of the elbow. The mechanism involves a varus force that first disrupts the lateral collateral ligament complex (specifically the LUCL), followed by the anteromedial coronoid facet fracturing against the medial trochlea. The AMCL typically remains intact, maintaining a medial hinge.

Question 62

Which of the following design modifications or surgical techniques in a reverse total shoulder arthroplasty (RTSA) most effectively decreases the incidence of inferior scapular notching?

Explanation

Inferior scapular notching in RTSA is caused by mechanical impingement of the humeral component against the scapular neck during adduction. To minimize this, the baseplate should be placed inferiorly (flush or slightly overhanging the inferior glenoid rim) and tilted inferiorly. Lateralizing the center of rotation and using a larger glenosphere also reduce notching.

Question 63

A 28-year-old professional volleyball player presents with insidious onset of right shoulder weakness. Examination reveals isolated atrophy of the infraspinatus with preserved supraspinatus bulk. External rotation strength is 3/5. Which of the following is the most likely etiology?

Explanation

Isolated infraspinatus atrophy implies compression of the suprascapular nerve distal to its innervation of the supraspinatus. This typically occurs at the spinoglenoid notch. In overhead athletes, this is frequently associated with posterior superior labral tears that act as a one-way valve, leading to a paralabral cyst that compresses the nerve in the spinoglenoid notch.

Question 64

A 40-year-old patient undergoes a radical neck dissection. Postoperatively, he notes shoulder weakness and an inability to abduct the arm above 90 degrees. Examination shows lateral winging of the scapula at rest, which worsens with attempted shoulder abduction. Injury to which nerve is most likely?

Explanation

Injury to the spinal accessory nerve (CN XI) causes trapezius palsy, leading to lateral winging of the scapula (the scapula translates laterally and rotates inferiorly). This is a known complication of neck dissections. Medial winging is caused by serratus anterior palsy (long thoracic nerve injury) and is accentuated by forward elevation or wall push-ups.

Question 65

A 13-year-old elite baseball pitcher presents with vague shoulder pain during the late cocking and early acceleration phases of throwing. Radiographs show widening and sclerosis of the proximal humeral physis. What is the most appropriate initial management?

Explanation

'Little League shoulder' is a proximal humeral epiphysiolysis (stress fracture of the physis) caused by repetitive torsional forces during throwing. Treatment involves absolute cessation of throwing (usually for 3 months) until symptoms resolve and radiographs show healing, followed by a gradual return-to-throwing program.

Question 66

A 45-year-old female sustains an elbow injury. Radiographs reveal a coronal shear fracture of the distal humerus involving the capitellum and extending medially into the lateral trochlear ridge. Which classification best describes this fracture, and what is the preferred treatment?

Explanation

A coronal shear fracture involving the capitellum and lateral trochlear ridge is classified as a Bryan-Morrey Type IV (McKee modification). The involvement of the lateral trochlear ridge compromises elbow stability, making open reduction and internal fixation (typically with headless compression screws) the standard of care to restore articular congruity and stability.

Question 67

Recent anatomical studies, notably by Gerber et al., have redefined the primary arterial blood supply to the humeral head. Which vessel provides the dominant blood supply and is most at risk of disruption in a severe 4-part proximal humerus fracture?

Explanation

While older literature suggested the anterior humeral circumflex artery (arcuate branch) was the main blood supply to the humeral head, newer quantitative studies (e.g., Gerber et al., JBJS 1990) established that the posterior humeral circumflex artery provides the dominant intraosseous vascularity to the humeral head.

Question 68

A 29-year-old male bodybuilder feels a pop in his anterior axilla while bench pressing. Examination reveals loss of the anterior axillary fold and weakness in shoulder internal rotation. Which anatomical portion of the pectoralis major tendon is most commonly torn, and what is its normal insertion pattern on the humerus?

Explanation

Pectoralis major ruptures most commonly involve the sternal head during heavy eccentric loading (bench press). As the muscle inserts onto the lateral lip of the bicipital groove, the tendon twists 180 degrees such that the inferior (sternal) head inserts deep (posterior) and proximal to the superior (clavicular) head.

Question 69

A 25-year-old cyclist falls directly onto his shoulder. Radiographs demonstrate the distal clavicle is displaced superiorly by 200% compared to the uninjured side. Which structures are disrupted in this specific grade of acromioclavicular (AC) joint injury?

Explanation

This describes a Rockwood Type V AC joint separation, characterized by >100% (up to 300%) superior displacement of the distal clavicle. Pathologically, it involves rupture of the AC ligaments, the coracoclavicular (CC) ligaments, and extensive detachment/tearing of the deltotrapezial fascia, allowing the clavicle to severely elevate subcutaneously.

Question 70

A 32-year-old male sustains a comminuted radial head fracture from a high-energy fall. During examination, he reports severe ipsilateral wrist pain. Radiographs suggest disruption of the distal radioulnar joint (DRUJ). What is the most appropriate management of the radial head to prevent long-term proximal radial migration?

Explanation

The patient has an Essex-Lopresti injury: radial head fracture, interosseous membrane tear, and DRUJ disruption. Radial head excision is absolutely contraindicated as it will result in severe proximal migration of the radius, ulnocarpal impaction, and chronic wrist pain. Radial head replacement (arthroplasty) is required to restore longitudinal forearm stability.

Question 71

In a patient with a suspected acute distal biceps tendon rupture, the O'Driscoll Hook Test is performed. The examiner attempts to hook an index finger under the intact biceps tendon. Which structure can yield a false-negative Hook test by remaining intact despite a complete avulsion of the main distal biceps tendon?

Explanation

The lacertus fibrosus (bicipital aponeurosis) can remain intact even when the primary distal biceps tendon is completely avulsed from the radial tuberosity. An intact lacertus fibrosus limits proximal retraction of the muscle belly and can simulate an intact tendon on palpation, potentially leading to a false-negative Hook test.

Question 72

A 30-year-old recreational weightlifter complains of vague posterior shoulder pain and weakness. An MRI reveals an isolated paralabral cyst in the quadrilateral space. Which muscle is most likely to demonstrate denervation changes on electromyography (EMG)?

Explanation

The quadrilateral space contains the axillary nerve and the posterior humeral circumflex artery. Compression here (Quadrilateral Space Syndrome) predominantly affects the axillary nerve branches, notably causing denervation and atrophy of the teres minor muscle, and sometimes the deltoid.

Question 73

A 21-year-old collegiate baseball pitcher presents with right shoulder pain. Examination reveals 25 degrees of internal rotation and 130 degrees of external rotation on the right, compared to 60 degrees of internal rotation and 95 degrees of external rotation on the left. The total arc of motion is symmetric. What is the most appropriate primary treatment?

Explanation

This pitcher exhibits Glenohumeral Internal Rotation Deficit (GIRD) with a preserved total arc of motion (155 degrees bilaterally). This is a physiologic adaptation in throwers caused by posteroinferior capsular contracture. The primary treatment is nonoperative, focusing on posteroinferior capsular stretching (sleeper stretches, cross-body adduction).

Question 74

A 42-year-old female sustains a 'terrible triad' injury to her elbow. Surgical intervention is planned. Which of the following describes the most widely accepted sequence of surgical repair to predictably restore stability?

Explanation

The classic, widely accepted sequence for repairing a terrible triad of the elbow follows a deep-to-superficial (or inside-out) approach: 1) Coronoid fracture fixation or capsular repair, 2) Radial head fixation or arthroplasty, and 3) Lateral collateral ligament (LCL) complex repair. The MCL is typically only explored if gross instability remains after these three steps.

Question 75

A 9-year-old male gymnast presents with lateral elbow pain and stiffness. Radiographs show sclerosis and fragmentation of the entire capitellum without a discrete osteochondral defect or loose body. What is the most likely diagnosis, and what is the expected outcome with rest?

Explanation

Panner's disease is an osteochondrosis of the capitellum affecting children (usually <10 years old). It involves the entire capitellum, presents with lateral elbow pain, and almost always resolves spontaneously with rest. In contrast, Osteochondritis Dissecans (OCD) of the capitellum affects older adolescents (12-16) and has a much higher rate of loose body formation requiring surgery.

Question 76

A 28-year-old weightlifter presents with medial elbow pain and a snapping sensation when moving from flexion to extension. Examination shows ulnar neuropathy symptoms and a palpable 'double snap' over the medial epicondyle during flexion. Ultrasound demonstrates dynamic subluxation of the ulnar nerve along with an adjacent muscular structure. What is the involved muscular structure?

Explanation

Snapping triceps syndrome occurs when the medial head of the triceps dynamically subluxates over the medial epicondyle during elbow flexion. It often pushes the ulnar nerve out of the cubital tunnel ahead of it, causing a characteristic 'double snap' (first the nerve, then the triceps) and secondary ulnar neuropathy.

Question 77

A 35-year-old male suffers a seizure and presents with his shoulder locked in internal rotation. A CT scan confirms an irreducible posterior shoulder dislocation with a reverse Hill-Sachs lesion (anteromedial humeral head impaction) involving 35% of the articular surface. What is the most appropriate surgical management for this humeral head defect to prevent recurrent instability?

Explanation

For a reverse Hill-Sachs lesion involving 20-40% of the articular surface, filling the defect is required to prevent it from engaging the posterior glenoid rim. The modified McLaughlin procedure (transfer of the lesser tuberosity with the attached subscapularis tendon into the defect) is the standard of care for defects of this size.

Question 78

A 25-year-old male with a complete, irreversible flail arm from a brachial plexus injury is planned for a glenohumeral arthrodesis to provide a stable proximal strut for eventual hand positioning (following distal reconstruction). What is the currently recommended optimal position for shoulder arthrodesis?

Explanation

Modern recommendations for shoulder arthrodesis advocate for a position of 20-30 degrees of abduction, 20-30 degrees of forward flexion, and 20-30 degrees of internal rotation. This minimizes disabling scapular winging at rest while allowing the hand to reach the mouth. Historical positions with higher abduction led to severe pain and winging.

Question 79

A 45-year-old male on chronic hemodialysis falls directly onto his elbow. He presents with an inability to actively extend his elbow against gravity. A lateral radiograph demonstrates a small cortical avulsion fracture (fleck sign) 1 cm superior to the olecranon tip. What is the most likely diagnosis?

Explanation

Chronic renal failure is a significant risk factor for tendon ruptures. The inability to extend the elbow against gravity, combined with a 'fleck sign' (small avulsion off the olecranon tip) on a lateral radiograph, is pathognomonic for a complete triceps tendon rupture, which requires operative repair.

Question 80

A 25-year-old male sustains a closed, distal-third spiral fracture of the humerus (Holstein-Lewis fracture). On initial presentation in the emergency department, he is unable to extend his wrist or fingers. He undergoes closed reduction and splinting. Post-reduction examination shows his radial nerve deficit is unchanged. What is the next best step in management?

Explanation

This patient has a primary radial nerve palsy associated with a closed humeral shaft fracture. The vast majority of these are neuropraxias that will recover spontaneously. The standard of care is observation for 3-4 months. Immediate surgical exploration is indicated for open fractures, associated vascular injuries, or a secondary palsy (palsy that occurs newly after closed reduction).

Question 81

A 45-year-old male sustains a 'terrible triad' injury of the elbow. What is the generally recommended surgical sequence for reconstructing this injury pattern?

Explanation

The standard surgical sequence for a terrible triad is deep-to-superficial: coronoid fixation first, followed by radial head repair or replacement, and then lateral collateral ligament (LCL) repair. The MCL is only repaired if the elbow remains unstable after these steps.

Question 82

A 30-year-old volleyball player presents with isolated weakness in external rotation of the shoulder. MRI reveals a paralabral cyst. Compression of the suprascapular nerve at the spinoglenoid notch will typically result in denervation of which of the following muscles?

Explanation

The suprascapular nerve innervates the supraspinatus before passing through the spinoglenoid notch. Therefore, a cyst at the spinoglenoid notch selectively compresses the distal nerve branch, causing isolated infraspinatus denervation.

Question 83

When performing a two-incision distal biceps tendon repair, how should the forearm be positioned during the posterolateral muscle-splitting approach to the radial tuberosity to maximally protect the posterior interosseous nerve (PIN)?

Explanation

During the posterior approach to the radial tuberosity, the forearm must be placed in full pronation. This shifts the posterior interosseous nerve (PIN) anteriorly, moving it safely away from the operative field.

Question 84

A 25-year-old male undergoes a Latarjet procedure for recurrent anterior shoulder instability. Postoperatively, he has profound weakness in elbow flexion and decreased sensation over the lateral forearm. Which nerve was most likely injured during coracoid retraction?

Explanation

The musculocutaneous nerve typically enters the coracobrachialis 5 to 8 cm distal to the coracoid process. Vigorous medial retraction of the conjoined tendon during a Latarjet procedure places this nerve at high risk for neuropraxia.

Question 85

According to the Hertel criteria, which of the following radiographic features is the most reliable predictor of subsequent avascular necrosis (AVN) following a proximal humerus fracture?

Explanation

Hertel identified three major risk factors for AVN in proximal humerus fractures: metaphyseal extension less than 8 mm, disruption of the medial hinge, and an anatomical neck fracture pattern.

Question 86

A patient with posterolateral rotatory instability (PLRI) of the elbow demonstrates a positive pivot-shift test. Which essential ligamentous structure is deficient in this condition?

Explanation

Posterolateral rotatory instability (PLRI) is caused by insufficiency of the lateral ulnar collateral ligament (LUCL). Reconstruction of the LUCL is required to restore posterolateral stability to the elbow.

Question 87

In a patient undergoing total elbow arthroplasty (TEA) for rheumatoid arthritis, a triceps-sparing (triceps-on) approach is utilized. Compared to a triceps-reflecting approach, the triceps-sparing approach is primarily associated with a decreased risk of which complication?

Explanation

Triceps-sparing approaches maintain the anatomic insertion of the triceps tendon on the olecranon. This significantly reduces the postoperative risk of triceps weakness or insufficiency compared to approaches that detach and repair the mechanism.

Shoulder And Elbow: Review | Dr Hutaif Shoulder & Elbow -...

Shoulder And Elbow: And Emqs A Review | Dr Hutaif Shoul -...

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Shoulder And Elbow: And Emqs A Review | Dr Hutaif Shoul -...

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