Labral tears are often caused by a direct injury to the shoulder, such as falling on an outstretched hand. The labrum can also become torn from the wear and tear of activity, a condition called overuse. An injured labrum can lead to shoulder instability. The extra motion of the humerus within the socket causes additional damage to the labrum. An extremely unstable shoulder may slip or dislocate. This can also cause the labrum to tear.
The main symptom caused by a labral tear is a sharp pop or catching sensation in the shoulder during certain shoulder movements. This may be followed by a vague aching for several hours. At other times, the tear may not cause any pain. Shoulder instability from a damaged labrum may cause the shoulder to feel loose, as though it slips with certain movements.