I keep hearing about athletes who tear their rotator cuff. What is it and why do they tear it?

The rotator cuff is a group of four muscles and several tendons around the top of the humerus, the bone that connects the arm to the shoulder. It helps you move your arm in the many directions it's able to. If you tear one of the tendons, you end up with a torn rotator cuff. This can cause quite a bit of pain and make it hard to use your arm properly.

Rotator cuffs are torn when the arm is subjected to heavy or sudden stresses. In the case of a baseball or football player, this can be from throwing the ball too hard too often. The tears are repaired with surgery, but how effective the surgery is depends on how badly it's torn and how many of the tendons are torn. If you tear two or more tendons, your condition is called a massive rotator cuff injury.