There seems to be a lot of talk, and some confusion, about the rotator cuff. It’s not just one muscle, it’s made up of 4 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 arm.
Each one of these muscles is part of the rotator cuff and plays an important role:
- Supraspinatus. This holds your humerus in place and keeps your upper arm stable. And helps lift your arm.
- Infraspinatus. This is the main muscle that lets you rotate and extend your shoulder.
- Teres Minor. This is the smallest rotator cuff muscle. Its main job is to assist with rotation of the arm away from the body.
- Subscapularis. This holds your upper arm bone to your shoulder blade and helps you rotate your arm, hold it straight out and lower it.