The glenoid labrum is a rubbery fibrocartilage ring that encircles the socket of the shoulder and provides increased depth and stability to the shoulder joint. Labrum disorders generally come in two forms, those related to the wear and tear effects of normal shoulder use and aging, and those that occur as a result of acute injury.
The labrum can be injured anywhere throughout its course but chronic overuse injury most commonly occurs in the superior aspect where it is a termed a superior labrum anterior and posterior (SLAP) tear. SLAP tears are quite common in those of middle age or older and in this setting may not need surgery. SLAP tears that exist as the result of an injury or that are clearly impairing shoulder function are more likely to require surgical repair. SLAP tears can be elusive to identify even with the use of imaging such as MRI scan and the ultimate diagnosis involves a combination of clinical history, physical examination and imaging tests.
The labrum is also injured in cases of acute traumatic shoulder dislocation where the ball becomes separated from the socket. Remarkably, the labrum and the ligaments that attach to it heal adequately following some dislocations and a percentage of patients never require surgical treatment. In many cases, however, the healing of the labrum and shoulder ligaments is incomplete or improperly positioned and surgical repair of the labrum and ligaments is necessary to restore shoulder stability.