Teres minor is a narrow muscle on the underside of the upper arm that connects the shoulder blade to the upper arm. It’s overlapped by the teres major and infraspinatus muscles.

The head of your upper arm bone, also called the humerus, fits into the socket of your shoulder blade, or scapula. When you extend your arm out away from your body, the rotator cuff muscles keep ...

Injuries to the upper arm muscles and tendons are most common in men 30-50, but women also may experience them. While bruising and swelling are obvious signs of an injury, ...