The rotator cuff is a group of four muscles and tendons that slip over the shoulder like an envelope. One or more of the tendons can develop a tear or tendonitis. It isn't always easy to identify which one(s) are involved.

Shoulder pain patterns aren't specific for rotator cuff tears (RCTs). For example pain can occur in the front, side, or back of the shoulder with a RCT. Since there aren't a lot of pain nerve endings in the rotator cuff itself, doctors think most of the pain comes from the bursa getting pinched.

The doctor can apply specific tests for each tendon to help narrow down the problem area. MRI or arthroscopic exam is really needed to show what is wrong and the extent of the damage. This information will help the doctor plan the best treatment approach.