Definition
- Superior Labrum Anterior & Posterior
- Lesions of the Superior labral complex at biceps insertion
Aetiology
Two mechanisms 1. Compression force applied to GHJ
- Commonest
- FOOSH
- Arm in abduction & forward flexion
- Head subluxes superiorly over glenoid edge
- Detaches labrum by shear & compression
- Force ↑ by biceps co-contraction
2. Traction on Arm
- Sudden pull on arm
- Grab while falling
- Overhead motion
- Throwing
Epidemiology
- Young athletes involved in overhead throwing activities
- Most common in young males
- Often associated with rotator cuff tear or other pathology > 50%
Anatomy
Pathology
Classification
Snyder – based on arthroscopic findings
Type 1 Frayed
- Fraying & degeneration of superior labrum
- No detachment of labrum or biceps
- 11%
Type 2 Detached
- Detached
- Superior labrum & attached biceps tendon stripped off glenoid
- Differentiate from normal anatomy
- Articular cartilage of glenoid normally extends to the attachment of labrum
- 41%
Type 3 Bucket handle tear of superior labrum
- Displacement of central rim of labrum into joint
- Peripheral labrum & biceps tendon attached to glenoid
- 33%
Type 4 Bucket handle involving biceps
- Bucket handle tear of superior labrum
- Extension into biceps tendon which remains attached but with partial tear
Added by Miller et al 1997
Type 5 Labral tear + SLAP (extension of type 2 further down labrum)
Type 6 Superior flap tear (like parrot-beak tear of meniscus)
Type 7 Capsular tear + SLAP
History
- Pain in shoulder with overhead activities
- Catching or popping with overhead activities
- mimic cuff tear
Examination
1. Speed’s Test Positive
2. McMurray’s Shoulder Test Positive
- Compression-Rotation test
- Patient supine
- Shoulder abducted 90°
- Elbow Flexed 90°
- Compression force to humerus
- Humerus rotated
- Attempt to trap torn labrum
- Positive if pain & click
3. Positive apprehension 39%, positive apprehension suppression 4%
Investigations
May be demonstrated on
1. CT-Arthrogram
2. MRI with Gadolinium
- Sensitivity 96% with arthrography
- Less with standard MR
- Buford complex normal varient
- Cordlike MGHL attaches to base biceps
- With absence of labral tissue
- Often missed or misdiagnosed
3. Arthroscopy
- Definitive diagnostic technique
Differential Diagnosis
Treatment
Usually arthroscopic diagnosis
Treated at time of Arthroscopy
Consists of
- Shaving of frayed labrum
- Abrasion of superior rim of glenoid (encourages healing)
- Reattachment of superior labrum with bone tacks or sutures
- Biceps tenodesis to bicipital groove if significant biceps involvement
- Capsule repair if involved
Type 1 Debridement
Type 2 Debridement & fixation back to glenoid
Type 3 Debridement
Type 4 Debridement & possible biceps tenodesis
- If less than 30% of tendon involved : simply resect
- If > 30% tendon involved : biceps tenodesis to bicipital groove
Type 5 Stabilise both
Type 6 Debridement
Type 7 Repair & stabilise
Postoperative
- 4-5 weeks before active biceps strengthening
- No stressful biceps activity for 3 months
Results variable with satisfactory results up to 2 years
Maybe relationship with glenohumeral instability