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Question 2381

Topic: Shoulder & Hip Sports

A 22-year-old athlete presents with a recurrent anterior shoulder dislocation. An MRI shows an anterior labral tear and a distinct impaction fracture on the posterolateral aspect of the humeral head. Which of the following best describes this bony defect?

. Reverse Hill-Sachs lesion
. Bankart lesion
. Hill-Sachs lesion
. ALPSA lesion
. GLAD lesion

Correct Answer & Explanation

. Reverse Hill-Sachs lesion


Explanation

An anterior shoulder dislocation can result in the posterolateral aspect of the humeral head impacting forcefully against the hard anterior glenoid rim, causing an impaction fracture known as a Hill-Sachs lesion. A reverse Hill-Sachs lesion is an anteromedial impaction fracture seen with posterior dislocations. A Bankart lesion is an avulsion of the anterior-inferior labrum from the glenoid.

Question 2382

Topic: Shoulder & Hip Sports

During an arthroscopic rotator cuff repair, a surgeon identifies a massive, retracted tear involving the entirety of the subscapularis tendon off its footprint on the lesser tuberosity. The surgeon needs to understand the innervation to mobilize the muscle safely. Which of the following peripheral nerves provide the primary motor innervation to the subscapularis?

. Suprascapular nerve
. Axillary nerve
. Upper and lower subscapular nerves
. Musculocutaneous nerve
. Thoracodorsal nerve

Correct Answer & Explanation

. Suprascapular nerve


Explanation

The subscapularis muscle originates on the subscapular fossa and inserts on the lesser tuberosity, functioning primarily as an internal rotator of the humerus. It is innervated by the upper and lower subscapular nerves, which are branches of the posterior cord of the brachial plexus. The suprascapular nerve innervates the supraspinatus and infraspinatus. The axillary nerve innervates the deltoid and teres minor. The thoracodorsal nerve innervates the latissimus dorsi. The musculocutaneous nerve innervates the anterior compartment of the arm (coracobrachialis, biceps, brachialis).

Question 2383

Topic: Shoulder & Hip Sports

In calculating the Instability Severity Index Score (ISIS) for an 18-year-old competitive rugby player with recurrent anterior shoulder instability, which of the following factors would contribute points indicating a higher risk of recurrence after an arthroscopic Bankart repair?

. Age > 20 years
. Absence of a Hill-Sachs lesion on AP radiograph
. Participation in non-contact sports
. Loss of normal contour of the glenoid on AP radiograph
. Positive apprehension test at 45 degrees of abduction

Correct Answer & Explanation

. Age > 20 years


Explanation

The ISIS score evaluates the risk of recurrence after arthroscopic anterior shoulder stabilization. Points are awarded for: age < 20 years (2 pts), participation in competitive sports (2 pts), contact sports (1 pt), loss of inferior glenoid contour on AP radiograph (2 pts), and visible Hill-Sachs lesion on AP radiograph (2 pts). A score > 6 suggests a high risk of failure with arthroscopic repair, and Latarjet should be considered.

Question 2384

Topic: Shoulder & Hip Sports

A 45-year-old male sustains a traumatic subscapularis tear. Physical exam reveals increased passive external rotation compared to the contralateral side. Which special test is most specific for an isolated tear of the upper portion of the subscapularis tendon?

. Lift-off test
. Belly-press test
. Bear-hug test
. Hornblower's sign
. Neer impingement sign

Correct Answer & Explanation

. Lift-off test


Explanation

The Bear-hug test is highly sensitive and specific for identifying tears involving the upper portion of the subscapularis. The Lift-off test is generally more effective at evaluating the inferior portion of the subscapularis. The Belly-press test evaluates the overall subscapularis but can be compensatory.

Question 2385

Topic: Shoulder & Hip Sports

A 23-year-old professional baseball pitcher presents with posterior shoulder pain during the late cocking phase of throwing. MRI arthrogram is likely to reveal which of the following classic findings associated with internal impingement?

. Articular-sided partial tear of the infraspinatus and posterosuperior labral fraying
. Bursal-sided partial tear of the supraspinatus and subacromial bursitis
. Tear of the subscapularis and medial dislocation of the biceps tendon
. Anterosuperior labral tear (SLAP) and complete supraspinatus tear
. Bony Bankart lesion and Hill-Sachs defect

Correct Answer & Explanation

. Articular-sided partial tear of the infraspinatus and posterosuperior labral fraying


Explanation

Internal impingement occurs during hyper-abduction and external rotation (late cocking phase). The greater tuberosity impinges against the posterosuperior glenoid margin, compressing the posterosuperior rotator cuff (supraspinatus/infraspinatus junction) and the posterosuperior labrum. This leads to articular-sided partial "kissing" lesions of the cuff and labrum.

Question 2386

Topic: Shoulder & Hip Sports

A 24-year-old rugby player has recurrent anterior shoulder instability. CT scan with 3D reconstruction reveals 25% anterior glenoid bone loss. A Latarjet procedure is planned. Which of the following accurately describes the 'sling effect' provided by the Latarjet procedure?

. The subscapularis is passed over the conjoint tendon.
. The conjoint tendon acts as a sling across the anterior and inferior capsule when the arm is abducted and externally rotated.
. The coracoacromial ligament is sutured to the subscapularis.
. The long head of the biceps provides a dynamic depressor effect.
. The pectoralis minor tendon is used to reinforce the inferior capsule.

Correct Answer & Explanation

. The subscapularis is passed over the conjoint tendon.


Explanation

The Latarjet procedure stabilizes the shoulder via three mechanisms: 1) the bone block increases the anteroposterior diameter of the glenoid (bony effect); 2) the conjoint tendon acts as a dynamic sling over the lower subscapularis and anteroinferior capsule in the abduction/external rotation position (sling effect); 3) capsular repair to the stump of the coracoacromial ligament (capsular effect).

Question 2387

Topic: Shoulder & Hip Sports

A 19-year-old female dancer complains of a painless snapping sensation over her lateral hip when she walks. Examination reveals a palpable snap over the greater trochanter when the hip is moved from flexion to extension. Which structure is most commonly implicated in this condition?

. Iliopsoas tendon
. Rectus femoris tendon
. Iliotibial band
. Gluteus medius tendon
. Ischiofemoral ligament

Correct Answer & Explanation

. Iliopsoas tendon


Explanation

External snapping hip syndrome (coxa saltans) is caused by the snapping of the iliotibial (IT) band or the anterior border of the gluteus maximus over the greater trochanter during hip flexion and extension. Internal snapping hip is caused by the iliopsoas tendon snapping over the iliopectineal eminence or femoral head.

Question 2388

Topic: Shoulder & Hip Sports

A 25-year-old professional baseball pitcher complains of posterior shoulder pain during the late cocking phase of throwing. Physical exam shows a Glenohumeral Internal Rotation Deficit (GIRD) of 25 degrees compared to the contralateral side, and a positive posterior impingement sign.

What are the hallmark arthroscopic findings of internal impingement in the thrower's shoulder?

. Anterosuperior labral tear and subscapularis tear.
. Posterosuperior labral fraying and partial articular-sided supraspinatus/infraspinatus tendon tears (PASTA).
. Anterior Bankart lesion and Hill-Sachs defect.
. Superior labral tear from anterior to posterior (SLAP) extending into the biceps tendon.
. Complete rotator cuff tear with retraction.

Correct Answer & Explanation

. Anterosuperior labral tear and subscapularis tear.


Explanation

Internal impingement occurs when the arm is in extreme abduction and external rotation (late cocking phase). The greater tuberosity impinges against the posterosuperior glenoid rim. This pinches the posterior cuff and posterosuperior labrum, leading to 'kissing lesions': partial articular-sided tears of the posterior supraspinatus/anterior infraspinatus (PASTA) and posterosuperior labral fraying.

Question 2389

Topic: Shoulder & Hip Sports

A 55-year-old tennis player sustains a fall onto an outstretched hand. He complains of anterior shoulder pain and weakness. Physical exam reveals a positive 'bear-hug' test and increased external rotation compared to the normal side. Which tendon is primarily affected, and what structure is at risk for medial subluxation as a consequence?

. Supraspinatus tendon; long head of the biceps
. Subscapularis tendon; long head of the biceps
. Infraspinatus tendon; short head of the biceps
. Teres minor tendon; long head of the triceps
. Pectoralis major tendon; short head of the biceps

Correct Answer & Explanation

. Supraspinatus tendon; long head of the biceps


Explanation

The bear-hug test and belly-press test are specific for subscapularis tendon tears. An isolated subscapularis tear also leads to increased passive external rotation. The upper border of the subscapularis forms the medial wall of the bicipital groove. When the upper subscapularis tears, the long head of the biceps tendon can subluxate or dislocate medially out of the groove.

Question 2390

Topic: Shoulder & Hip Sports

A 35-year-old tennis player presents with anterior shoulder pain exacerbated by forward flexion and internal rotation. Examination demonstrates increased translation on the load-and-shift test and a positive bear-hug test. An MRI is obtained showing narrowing of the coracohumeral interval. Which structure is most likely to be injured in this condition?

. Supraspinatus tendon
. Subscapularis tendon
. Infraspinatus tendon
. Biceps anchor
. Inferior glenohumeral ligament

Correct Answer & Explanation

. Supraspinatus tendon


Explanation

Coracoid impingement syndrome typically occurs when the coracohumeral interval is narrowed (<6-7 mm), leading to impingement of the subscapularis tendon and the long head of the biceps. The bear-hug test is highly specific for evaluating a subscapularis tendon tear.

Question 2391

Topic: Shoulder & Hip Sports

A 28-year-old professional volleyball player presents with insidious onset of posterior shoulder pain and weakness. Physical examination reveals isolated atrophy of the infraspinatus muscle with normal supraspinatus bulk and strength. Where is the most likely site of nerve compression?

. Suprascapular notch
. Spinoglenoid notch
. Quadrilateral space
. Triangular interval
. Spinal accessory nerve traction

Correct Answer & Explanation

. Suprascapular notch


Explanation

Entrapment of the suprascapular nerve at the spinoglenoid notch affects only the infraspinatus muscle, leading to isolated atrophy and external rotation weakness. Entrapment at the suprascapular notch (more proximal) would affect both the supraspinatus and infraspinatus muscles. Paralabral cysts associated with posterior SLAP tears are a common cause of spinoglenoid notch compression in overhead athletes.

Question 2392

Topic: Shoulder & Hip Sports

A 24-year-old hockey player presents with groin pain with hip flexion and internal rotation. Radiographs are ordered to evaluate for femoroacetabular impingement (FAI). An elevated alpha angle is indicative of which morphology, and on what view is it best measured?

. Pincer morphology; AP pelvis radiograph
. Cam morphology; Dunn lateral radiograph
. Pincer morphology; False profile radiograph
. Cam morphology; Judet radiograph
. Mixed morphology; AP pelvis radiograph

Correct Answer & Explanation

. Pincer morphology; AP pelvis radiograph


Explanation

An elevated alpha angle (typically > 50-55 degrees) is indicative of Cam morphology (asphericity of the femoral head-neck junction). It is best measured on a Dunn lateral, cross-table lateral, or Meyer lateral radiograph. Pincer morphology is associated with acetabular overcoverage and evaluated with the lateral center-edge angle or crossover sign on an AP pelvis radiograph.

Question 2393

Topic: Shoulder & Hip Sports

A 19-year-old female dancer complains of a visible, audible 'snap' over the lateral aspect of her hip when moving from flexion to extension. She has tenderness over the greater trochanter. Which structures are most commonly involved in this condition?

. Iliopsoas tendon snapping over the iliopectineal eminence
. Iliotibial band snapping over the greater trochanter
. Rectus femoris snapping over the anterior inferior iliac spine
. Hamstring tendons snapping over the ischial tuberosity
. Gluteus medius snapping over the acetabular rim

Correct Answer & Explanation

. Iliopsoas tendon snapping over the iliopectineal eminence


Explanation

External snapping hip syndrome (coxa saltans) is most commonly caused by the iliotibial (IT) band or anterior border of the gluteus maximus snapping over the greater trochanter of the femur during hip flexion/extension. Internal snapping hip is caused by the iliopsoas tendon snapping over the iliopectineal eminence or femoral head.

Question 2394

Topic: Shoulder & Hip Sports

During a rotator cuff repair, an understanding of the vascular supply is essential. The 'critical zone' of the supraspinatus tendon, where tears most commonly initiate, is primarily located at what distance proximal to its insertion on the greater tuberosity?

. 0 to 5 mm
. 10 to 15 mm
. 20 to 25 mm
. 30 to 35 mm
. At the musculotendinous junction

Correct Answer & Explanation

. 0 to 5 mm


Explanation

The 'critical zone' of the supraspinatus tendon is an area of relative hypovascularity located approximately 10 to 15 mm proximal to its insertion on the greater tuberosity. This is the most common site for degenerative rotator cuff tears.

Question 2395

Topic: Shoulder & Hip Sports

A 26-year-old professional baseball pitcher presents with posterior shoulder pain during the late cocking phase of throwing. He exhibits a GIRD (glenohumeral internal rotation deficit) of 25 degrees. Which of the following best describes the pathophysiology of internal impingement in this patient?

. Impingement of the supraspinatus against the coracoacromial arch
. Impingement of the subscapularis against the coracoid process
. Impingement of the articular surface of the infraspinatus and posterior superior labrum between the greater tuberosity and posterior superior glenoid
. Impingement of the long head of the biceps within the bicipital groove
. Compression of the suprascapular nerve at the spinoglenoid notch

Correct Answer & Explanation

. Impingement of the supraspinatus against the coracoacromial arch


Explanation

Internal impingement (posterior superior glenohumeral impingement) occurs in overhead throwing athletes during the late cocking phase (abduction and maximal external rotation). It involves the impingement of the undersurface of the posterior supraspinatus and anterior infraspinatus along with the posterosuperior labrum between the greater tuberosity and the posterosuperior glenoid rim.

Question 2396

Topic: Shoulder & Hip Sports

A 22-year-old rugby player presents with recurrent anterior shoulder instability despite a prior arthroscopic Bankart repair. A revision MRI arthrogram demonstrates a 'J-sign' in the axillary pouch rather than the normal U-shape.

Which of the following describes the pathology?

. Avulsion of the anterior band of the IGHL from the glenoid with a bony fragment
. Humeral avulsion of the glenohumeral ligament (HAGL)
. Medialized attachment of the anterior labrum on the glenoid neck (ALPSA)
. Superior labrum anterior to posterior (SLAP) tear extending into the biceps root
. Engaging Hill-Sachs lesion

Correct Answer & Explanation

. Avulsion of the anterior band of the IGHL from the glenoid with a bony fragment


Explanation

A HAGL (Humeral Avulsion of the Glenohumeral Ligament) lesion occurs when the inferior glenohumeral ligament (IGHL) is avulsed from its humeral attachment. On a coronal MRI arthrogram, the normal U-shaped axillary recess is converted to a J-shape due to extravasation of contrast through the humeral-sided defect. Failure to recognize a HAGL lesion is a known cause of recurrent instability following an isolated Bankart repair.

Question 2397

Topic: Shoulder & Hip Sports

A 45-year-old manual laborer presents with a massive, irreparable posterosuperior rotator cuff tear involving the supraspinatus and infraspinatus. The subscapularis is completely intact. He demonstrates a lag sign and pseudoparalysis of external rotation, but maintains forward elevation to 130 degrees. Which of the following tendon transfers is biomechanically optimal to restore external rotation in this patient?

. Latissimus dorsi transfer
. Pectoralis major transfer
. Pectoralis minor transfer
. Teres major transfer
. Lower trapezius transfer

Correct Answer & Explanation

. Latissimus dorsi transfer


Explanation

In the setting of a massive irreparable posterosuperior rotator cuff tear with an intact subscapularis and preserved forward elevation, the primary functional deficit is loss of external rotation. The lower trapezius transfer, often augmented with an Achilles tendon allograft, has a superior line of pull matching the native infraspinatus compared to the latissimus dorsi, making it biomechanically optimal for restoring external rotation.

Question 2398

Topic: Shoulder & Hip Sports

A 22-year-old collegiate hockey player complains of insidious onset anterior groin pain, worse with deep hip flexion. Physical exam reveals a positive FADIR test. Plain radiographs, including a Dunn lateral view, demonstrate an abnormal head-neck junction. An alpha angle greater than what threshold is highly indicative of symptomatic Cam-type femoroacetabular impingement (FAI)?

. 35 degrees
. 45 degrees
. 55 degrees
. 75 degrees
. 85 degrees

Correct Answer & Explanation

. 35 degrees


Explanation

The alpha angle is used to quantify the severity of a Cam deformity in femoroacetabular impingement (FAI). It is measured on a lateral radiograph (like the Dunn view) or axial MRI/CT. An alpha angle > 50-55 degrees indicates a loss of normal sphericity at the femoral head-neck junction, characteristic of Cam impingement.

Question 2399

Topic: Shoulder & Hip Sports

A 26-year-old baseball pitcher presents with posterior shoulder pain that is most severe during the late cocking phase of throwing. He has a 20-degree glenohumeral internal rotation deficit (GIRD). Arthroscopic evaluation reveals 'internal impingement.' Which structures are pathologically abutting each other in this condition?

. Anterior supraspinatus tendon and the coracoacromial ligament
. Subscapularis tendon and the anterior superior labrum
. Long head of the biceps tendon and the superior margin of the subscapularis
. Bursal surface of the rotator cuff and the acromion
. Undersurface of the posterior supraspinatus/anterior infraspinatus and the posterosuperior glenoid labrum

Correct Answer & Explanation

. Anterior supraspinatus tendon and the coracoacromial ligament


Explanation

Internal impingement typically affects overhead-throwing athletes during the late cocking phase (maximum abduction and external rotation). It involves the pathologic abutment of the articular (undersurface) side of the posterior supraspinatus and anterior infraspinatus tendons against the posterosuperior glenoid labrum, leading to 'kissing lesions' (partial-thickness cuff tears and labral fraying).

Question 2400

Topic: Shoulder & Hip Sports

A 21-year-old ballerina presents with an audible and palpable 'clunk' deep in her anterior groin. This consistently occurs when she extends her hip from a flexed, abducted, and externally rotated position. She denies any history of trauma. What is the most likely anatomic cause of this specific snapping?

. Iliotibial band tracking over the greater trochanter
. Gluteus maximus tendon snapping over the greater trochanter
. Acetabular labral tear
. Iliopsoas tendon snapping over the iliopectineal eminence or femoral head
. Ischiofemoral impingement

Correct Answer & Explanation

. Iliotibial band tracking over the greater trochanter


Explanation

This is the classic presentation of Internal Snapping Hip syndrome (Coxa Saltans Interna). It is caused by the iliopsoas tendon snapping over the iliopectineal eminence or the anterior femoral head as the hip is moved from a flexed, abducted, and externally rotated position into extension and internal rotation. External snapping hip involves the IT band over the greater trochanter.