Front View of the Left Shoulder

Anatomical Overview

The term SLAP tear refers to a tear of the superior labrum of the shoulder. The labrum is a piece of fibrous tissue made of cartilage, called fibrocartilage, which surrounds the glenoid or the socket of the shoulder. It forms a rim like structure which aids in stabilizing the shoulder joint and provides an attachment for the ligaments of the shoulder.

The superior (upper) part of the labrum anchors one of the two tendons of the biceps muscle. If the arm is forcefully bent inward and twists at the shoulder, the humeral head acts as a lever and tears the biceps tendon and labrum cartilage from the glenoid bone in a front-to-back (anterior-posterior) direction.

What causes a SLAP tear?

A SLAP tear can be caused by many different ways. The most common cause is a fall or some other sort of injury to the shoulder. Dislocation of the joint is associated with SLAP tears but commonly occurs in sportsmen with weightlifting, throwing injury or tackle. Another cause of SLAP tears is repetitive overhead activities seen in tennis players, baseball players and volleyball players. Overhead and contact sports pose a greater risk of labral tears.  Also when the shoulder is in maximum abduction and external rotation, the peel-back and shear forces are maximized, increasing the chances of a SLAP lesion and its impact on the rotator cuff. The increased torsional forces on the rotator cuff cause fiber failure. Partial and full rotator cuff tears have been associated with up to 40 percent of SLAP lesions in overhead athletes. Shoulders with tight posteroinferior capsules are particularly at risk.

Inside View of Glenoid Cavity (shoulder socket)

What are common complaints?

The most common complaint is pain. The typical symptoms are pain at the top of the shoulder, clicking and pain with overhead activities. In addition, patients with SLAP tears will also complain of:

Diagnosis for SLAP lesions

A thorough physical, orthopedic and imagine should take place by a qualified sports medicine practicioner for proper diagnosis and treatment. Orthopedic tests place either a tensile or torsional load on the biceps—stressing the loose anchor of the biceps-superior labrum complex. This stress will elicit pain in those patients with a type II SLAP lesion.Xrays may be taken and MR arthrogram will most likely be recommended, which is a more sensitive imaging test than MRI due to injected contrast to detect tears and swelling.

Classification of SLAP Lesions

Categorizing SLAP depends on the morphology of the tear and the involvement of the long head of the biceps anchor to the superior labrum.  The image below reflect SLAP Lesion Tears grade 1-IV (image is looking into glenoid cavity/shoulder socket)

Type I

SLAP lesions were described as being indicative of isolated fraying of the superior labrum with a firm attachment of the labrum to the glenoid.  These lesions are typically degenerative in nature.  It is currently believed that the majority of the active population may have a Type I SLAP lesion.

Type II

SLAP lesions are characterized by a detachment of the superior labrum and the origin of the tendon of the long head of the biceps brachii from the glenoid resulting in instability of the biceps-labral anchor.  These is the most common type of SLAP tear.  Different types of patients and mechanisms of injuries will result in slightly different Type II lesions.  The majority of overhead athletes present with posterosuperior lesions while individuals who have traumatic SLAP lesions typically present with anterosuperior lesions.  These variations are important when selecting which special tests to perform based on the patient’s history and mechanism of injury.

Type III

SLAP lesions are characterized by a "bucket-handle" tear of the labrum with an intact biceps insertion.  The labrum tears and flips into the joint similar to a meniscus.  The important concept here is that the biceps anchor is attached, unlike a Type II.

Type IV

SLAP lesions have a bucket-handle tear of the labrum that extends into the biceps tendon.  In this lesion, instability of the biceps-labrum anchor is also present, similar to that seen in the type II SLAP lesion.  This is basically a combination of a Type II and III lesion.

(To further complicate things,  Maffet et al: AJSM ’95 noted that 38% of the SLAP lesions identified in their retrospective review of 712 arthroscopies were not classifiable using the I-IV terminology previously defined by Snyder et al (49).  They suggested expanding the classification scale for SLAP lesions to a total of 7 categories, adding descriptions for types V-VII as these 3 types typically involve a concomitant pathology in conjunction with a SLAP lesion)

Prevention and Treatment

If you have been diagnosed with a SLAP lesion type 2 or more, arthroscopy or surgical intervention may be necessary.  If type one SLAP lesion tear is suspected, exercise rehab, soft tissue therapy and physiotherapy (ultrasound, electrical stim) may be recommended to facilitate healing or pre-operative rehab.

*Incorporate these two stretches in your daily routine to avoid a SLAP tear lesion, or a type 1 lesion, from further progressing to type 2. Hold each stretch 30-60 seconds and can be performed multiple times throughout the day

Posterior Capsule stretch (keep arm in straight alignment, place support under head to avoid strain)	Pectoralis Minor Stretch (Stretch should involve both shoulders at same time)