Shoulder braces are designed to help prevent injuries and help repair the damage that has already occurred to the shoulder. They also serve to stabilize the joint for people who have injured their rotator cuff or damaged the ligaments in their shoulder.A rotator cuff is a group of four muscles that can tear or become strained from sports or other activities that involve repetitive overhead motion. In order to prevent this, the surrounding tendons and tissues need to be strengthened through rehabilitation exercises. Shoulder braces fall under one of two categories: immobilizers (non-movable) and stabilizers (movable). Stabilizers are designed to provide support for the shoulder, but also allow some range of motion. Immobilizers prevent all movement of the shoulder.Stabilizers are prescribed for those who have injured their rotator cuff or damaged the ligaments around their shoulder, or for those who are trying to protect a damaged area of their shoulder.