SLAP Tear: Understanding Superior Labrum Tears

What Is a SLAP Tear?

SLAP stands for Superior Labrum Anterior to Posterior — describing a tear in the cartilage ring (labrum) at the top (superior) of the shoulder socket (glenoid), extending from the front (anterior) to the back (posterior). Critically, the biceps tendon anchors to the top of the glenoid at exactly this location (the biceps anchor).

The labrum serves two functions in the shoulder:

Deepens the socket: Increases the depth of the shallow glenoid by 50%, improving ball-in-socket stability
Biceps anchor: Provides the attachment point for the long head of the biceps tendon

When this region tears, both shoulder stability and biceps function can be affected.

Classification

SLAP tears are classified into four types:

Type	Description
Type I	Fraying of the superior labrum, biceps anchor intact
Type II	Detachment of the biceps anchor from the glenoid (most common; requires repair)
Type III	Bucket-handle tear of superior labrum, biceps anchor intact
Type IV	Bucket-handle tear extending into the biceps tendon itself

Type II is by far the most common and clinically significant type.

Causes

Overhead throwing: Baseball pitching generates enormous rotational forces that stress the biceps anchor — SLAP tears are extremely common in pitchers
Traction injury: Sudden downward pull on the arm (catching a heavy object, preventing a fall)
Compression injury: Falling onto an outstretched arm
Degeneration: In older patients (>40), superior labrum fraying is a normal aging change

Who Gets SLAP Tears?

Baseball pitchers and overhead throwers (highest risk group)
Swimmers, tennis players, volleyball players
Weightlifters (especially bench press)
Workers performing repetitive overhead work

Symptoms

Deep, aching shoulder pain that is difficult to localize — often described as "inside the shoulder"
Mechanical symptoms: Clicking, popping, or locking with shoulder movement
Pain with overhead activities, especially the "late cocking" phase of throwing
Loss of velocity or accuracy in throwing athletes
Night pain
A sense of shoulder instability or "dead arm" in overhead athletes

Diagnosis

SLAP tears are notoriously difficult to diagnose clinically — no single clinical test is highly reliable.

Clinical tests (limited sensitivity):

O'Brien's active compression test
Biceps load test
Anterior slide test

MR Arthrogram (MRI with contrast injected into the joint) is the most sensitive imaging study for SLAP tears — more accurate than standard MRI for this injury.

Diagnostic arthroscopy: Definitive diagnosis requires looking inside the shoulder with an arthroscope.

Treatment

Conservative Treatment

Physical therapy: Posterior capsule stretching, rotator cuff strengthening, scapular stability
Activity modification: Reduced throwing volume
NSAIDs and occasional corticosteroid injections

Older, lower-demand patients (>40) often respond well to conservative management as superior labral changes are expected with age.

Surgical Treatment (SLAP Repair)

Arthroscopic repair using suture anchors to reattach the detached labrum/biceps anchor. Indicated for:

Young athletes with Type II tears failing conservative treatment
Overhead athletes wanting to return to high-level throwing

Biceps tenodesis: In patients over 35–40, or with associated biceps tendon pathology, the biceps tendon is detached from the glenoid and reattached lower on the humerus — a simpler, more reliable procedure with faster recovery than SLAP repair.

Recovery

SLAP repair: 6–12 months to return to overhead throwing
Biceps tenodesis: 3–5 months to return to sport