Glenoid Labrum Lesions

The glenoid labrum lesions is fibrocartilaginous tissue within the glenoid cavity of the shoulder joint. The purpose of the glenoid labrum is to provide stability and shock absorption within the joint.

A SLAP lesion (superior labrum, anterior [front] to posterior [back]) is a tear of the rim above the middle of the socket that may also involve the biceps tendon. A tear of the rim below the middle of the glenoid socket that also involves the inferior glenohumeral ligament is called a Bankart lesion. The glenoid, or socket joint of the shoulder, is surrounded by a fibrocartilaginous supporting structure called the labrum. Injuries to the tissue surrounding the shoulder socket can be caused by acute trauma or repetitive shoulder motions.

Typically, patients with SLAP injuries that are less severe, involving either a partially torn labrum or frayed labrum, will find that physical therapy alone will improve their symptoms. However, if symptoms do not resolve after 6-12 weeks of physical therapy, surgery is necessary for a full recovery.

Other Names

  • Labral Tear
  • Glenoid Labral Tear
  • Superior Labrum Anterior Posterior (SLAP) tear

Background

  • This page currently refers to all lesions of the Glenoid Labrum
  • Including:
    • Superior Labrum Anterior Posterior (SLAP) tear
    • Andrew’s Lesion
    • Anterior Labral Tear
    • Posterior Labral Tear
    • Antero-inferior Labral Tear
    • Postero-inferior Labral Tear
    • Inferior Tear
  • SLAP Tear
    • Accounts for 80-90% of labral pathology (need citation)
  • Anterior-inferior (Bankart)
    • Most common (need citation, conflicts with statement about SLAP tear)
  • Posterior
    • Rare, seen on only 2-6% of arthroscopies

Pathophysiology

  • Pathology can an be divided into 6 glenoid sectors per Synder

Pathoanatomy

  • Glenoid Labrum
    • Fibrocartilage of the shoulder joint
    • Runs along the outer rim of the glenoid
    • Provides up to 10% of glenohumeral stability
  • Other structures
    • Continuous with the insertion of the long head of the Biceps Brachii onto the supraglenoid tubercle
    • Glenohumeral Ligaments

SLAP Tear

  • SLAP: Superior Labrum from Anterior to Posterior
  • Accounts for 80-90% of labral pathology
  • Can be challenging to diagnose due to concomitant shoulder pathology
    • 88% of patients with arthroscopy confirmed SLAP tear have other intra-articular lesions
  • Due to tightness of posterior-inferior glenohumeral ligament, shifting GH contact posteriorly increases shearing forces

Causes

  • Can be acute or insidious
  • Occurs in throwing and overhead athletes in the dominant shoulder

Associated Injuries

  • Glenohumeral Internal Rotation Deficit
  • Internal Impingement
  • Rotator Cuff Tear
  • Instability
  • Scapular Dyskinesis

Andrew’s Lesion

  • Pure superior labrum detachment without extension into biceps footplate
  • Mainly found in throwers

Anterior Labral Tear

  • Pure anterior labral tear
  • Associated with a middle glenohumeral ligament tear
  • Rare
  • Location: Sector 2

Posterior Labral Tear

  • Rare, less common than anterior tear
  • Sector 6 labral injury
  • Due to posteriorly directed force
  • Sometimes referred to as a reverse bank
  • Weightlifting (bench press), football linemen (blocking), swimmers, gymnasts, wrestlers

Associated Injuries

  • Kim Lesion: Incomplete avulsion of the posterior inferior labrum

Antero-inferior Labral Tear

  • Associated injuries
    • Acute or chronic anterior Shoulder Instability
    • Injuries to the Glenohumeral Ligament Complex
    • Perth’s Lesion: Antero-inferior labral detachment
    • Gleno-labral Articular Disrupotion (GLAD)
    • Bankart Lesion
    • ALPSA lesion: Anterior Labroligamentous Periosteal Sleeve Avulsion
  • Sector 3, 4

Postero-inferior Labral Tear

Inferior Labral Tear

  • Sector 4 (between 4 o’clock and 8 o’clock position)
  • Poorly described in the literature with case reports and series only
  • In case series, dislocation does not appear to be associated
  • Suspect repetitive microtrauma
  • Unclear in limited case series
  • Patients endorse pain, not instability

Associated Injuries

  • Paralabral Cyst
  • General
    • Labral dysplasia (buferd complex)
    • Scapular hyperlaxity
    • Scapular Dyskinesis
  • Posterior
    • Weightlifting (bench press)
    • Football lineman (blocking)
    • Swimmers, gymnasts, wrestlers
  • SLAP
    • Glenohumeral Internal Rotation Deficit

Differential Diagnosis

  • Fractures
    • Proximal Humerus Fracture
    • Humeral Shaft Fracture
    • Clavicle Fracture
    • Scapula Fracture
    • First Rib Fracture (traumatic or atraumatic)
  • Dislocations & Seperations
    • Acromioclavicular Joint Separation
    • Glenohumeral Dislocation (Acute)
    • Sternoclavicular Joint Dislocation
    • Glenohumeral Instability (Chronic)
  • Arthropathies
    • Glenohumeral Arthritis
    • Acromioclavicular Joint Arthritis
  • Muscle & Tendon Injuries
    • Pectoralis Major Injuries
    • Pectoralis Minor Injuries
    • Proximal Biceps Tendon Injuries
    • Scapular Dyskinesis
  • Rotator Cuff
    • Rotator Cuff Tear
    • Rotator Cuff Tendonitis
    • Calcific Tendinitis of the Rotator Cuff
    • Subcoracoid Impingement Syndrome
  • Bursopathies
    • Subacromial Bursitis
    • Scapulothoracic Bursitis
  • Ligament Injuries
    • Glenoid Labral Tears
  • Neuropathies
    • Suprascapular Nerve Injury
    • Parsonage-Turner Syndrome
    • Quadrilateral Space Syndrome
    • Winged Scapula
  • Other
    • Adhesive Capsulitis
    • Paget-Schroetter Syndrome
  • Pediatrics
    • Coracoid Avulsion Fracture
    • Humeral Head Epiphysiolysis (Little League Shoulder)

Symptoms

  • A sense of instability in the shoulder.
  • Shoulder dislocations.
  • Pain, usually with overhead activities.
  • Catching, locking, popping, or grinding.
  • Occasional night pain or pain with daily activities.
  • Decreased range of motion.
  • Loss of strength.

Diagnosis

  • History
    • Patients will typically report pain, instability
    • May have a history of shoulder injury or dislocation
    • Pain will be vague, nonspecific
    • May endorse clicking or popping
    • Throwers may endorse a loss of throwing velocity, ball control or changes to mechanics
  • Physical: Physical Exam Shoulder
    • Important to perform a thorough shoulder examination
    • The labrum in general is best tested with provocative testing
  • Special Tests
    • Jobe Relocation Test: Supine with abducted, externally rotated shoulder and a posterior force
    • Internal Rotation Resistance Test: Arm abducted to 90°, internally and externally rotate against resistance
    • Crank Test: Hyper-abducted shoulder, axial load on humerus with internal and external rotation
    • OBriens Test: Shoulder flex to 90°, upward force against resistance in supination and pronation
    • Apprehension Test: Flexes elbow to 90°, abduct shoulder to 90°, slowly externally rotate the shoulder
    • Load and Shift Test: Arm slightly abducted, apply anterior-posterior force to humeral head assessing translation
    • Clunk Test: fully abduct arm then apply anterior force
    • Anterior Slide Test: Place the patient’s hand on the hip, apply anterior force along the axis of the humerus
    • New Pain Provocation Test: Arm abducted, elbow flexed to 90°, supinate and pronate the forearm
  • Posterior-inferior
    • Kim Test: Arm abducted to 90°, apply axial load and elevate arm cranially and anterior
    • Jerk Test: Arm abducted to 90°, internally rotated with axial load, and arm is abducted anteriorly in the same plane
  • SLAP Lesion (not specific)
    • Passive Compression Test: Arm abducted to 30°, externally rotated, axial load into joint with extension
    • Dynamic Labral Shear Test: Externally rotate the arm and abduct to 90°, bring form 90-120° to reproduce symptoms
    • Compression Rotation Test: Shoulder and elbow flexed to 90°, apply a compressive force, rotate the humerus
  • Inferior
    • Sulcus Sign: Place axial traction on affected limb with arm resting at side
  • Posterior
    • Posterior Apprehension Test: Apply a posterior force through flexed, adducted shoulder
  • Biceps
    • Speeds Test: Shoulder flex to 90°, upward force against resistance in supination and pronation
    • Biceps Load Test: Resisted flexion with the arm abducted to 90°, maximal external rotation
    • Biceps Load Test II: Resisted flexion with the arm abducted to 120°, maximal external rotation
    • Yergasons Test: Elbow flexed to 90°, forearm pronated, attempt to supinate against resistance
Coronal T2-weighted fat-suppressed MRI shows superior labral tear and overlying paralabral cyst (arrow) and a low-grade intrasubstance tear of the supraspinatus tendon (arrowhead)[7]

Radiographs

  • Start with Standard Radiographs Shoulder
  • Often normal
  • Useful for excluding other causes of shoulder pain
  • Posterior: may see glenoid retroversion, posterior glenoid erosion

CT

  • Arthrography[8]
    • Sensitivity: 94-98%
    • Specificity: 73-88%
  • The advantage over MRI in evaluating bone

MRI

  • Arthrography
    • Sensitivity: 82-89%
    • Specificity: 91-98%
    • Arthrography may not be necessary if magnet is 3T or larger[9]
  • SLAP: T2 signal intensity between superior labrum, lateral to glenoid rim, posterior to biceps

Classification

SLAP Tear

  • Type I: degenerative lesion, fraying of the labrum
  • Type II: Labrum, long head of biceps torn
  • Type III: Bucket handle detachment of superior aspect
  • Type IV: Type III lesion extending into the biceps brachii
  • Type V: Type II tear with anterior shoulder instability
  • Type VI: Large labral flap without detachment of biceps
  • Type VII: Type II tear with affected middle, inferior glenohumeral ligament tear
  • Type VIII: Type II tear involving cartilage adjacent to biceps footplate

Treatment

Nonoperative

  • Posterior
    • First line treatment
    • Activity Modification
    • NSAIDS
    • Physical Therapy
  • SLAP
    • First-line treatment
    • Address GIRD if present, stretch the posterior capsule
    • Activity Modification
    • NSAIDS
    • Physical Therapy
    • Similar outcomes to surgical management for pain, function, and QOL. However, the return to overhead sports was inferior[10]

Operative

  • Posterior
    • Indications: Failure of conservative management
    • Technique: Posterior labral repair, capsulorrphaphy
  • SLAP
    • Indications: Failure of conservative management
    • Technique: arthroscopic debridement, possible repair of the labrum, biceps tenotomy or tenodesis