GLENOID LABRUM TEAR – COURSE OF INJURY (Shoulder) A glenoid labrum tear usually begins with a specific event or repeated stress to the shoulder. The labrum is a fibrocartilaginous rim that deepens the shoulder socket and adds stability. Injury commonly occurs during a fall on an outstretched hand, a sudden traction force, shoulder dislocation, or repetitive overhead activities like throwing, swimming, or weightlifting. In athletes, the damage may start subtly, without a single memorable injury.