Superior Labrum Anterior Posterior
The shoulder is a complicated joint that allows an incredible range of motion. The shoulder joint consists of the humeral head (ball) and the glenoid (socket).
The labrum is a small rim of cartilage that acts to deepen the glenoid and keep the shoulder from dislocating. At the top part of the glenoid, one of the two biceps tendons originates off the labrum and runs along the top of the humeral head and into the arm.
Labral tears are classified by type:
I. Fraying of the superior labrum, often degenerative
II. Detachment of the superior labrum with biceps anchor attached
III. Bucket handle tear of the superior labrum with the biceps anchor intact
IV. Bucket handle tear of the superior labrum with the biceps anchor attached
Injuries to the superior labrum are very common, especially in throwers and active athletes. These injuries are commonly called “SLAP” tears (Superior Labrum Anterior and Posterior). Injuries either occur from repetitive activity such as throwing or serving in tennis, or from a fall onto the shoulder. Labral injuries are commonly seen along with shoulder separations as well.
Patients with labral tears often complain of pain with overhead activity, pain with lifting heavy objects, and inability to perform well in sports.
The diagnosis of labral tears is made by the patients’ history and physical exam. An MRI is often performed to confirm the diagnosis, and can be very helpful in determining the type of labral injury. The MRI is usually performed with a small amount of dye placed into the joint (arthrogram).