Infraspinatus

The infraspinatus is a muscle located on the back of your shoulder blade (scapula). It plays a key role in shoulder movement and stability by helping you rotate your arm outward and providing support to keep the shoulder joint stable. This muscle is part of the rotator cuff group, which holds the upper arm bone securely in the shoulder socket. When the infraspinatus functions properly, it allows smooth, controlled shoulder movements, such as reaching or throwing. Injury or weakness here can lead to shoulder pain and limited mobility.