The rotator cuff is a group of tendons and muscles in your shoulder. They form a “cuff” over the top end of your arm. It helps you lift and rotate your arm. And it keeps the shoulder steady as your ...

What Is a Rotator Cuff? Your rotator cuff is made up of muscles and tendons that keep the ball (head) of your upper arm bone (humerus) in your shoulder socket. It also helps you raise and rotate your ...