The infraspinatus is a muscle located in the shoulder region, specifically part of the rotator cuff. It originates from the infraspinous fossa of the scapula and attaches to the greater tubercle of the humerus. This muscle plays a crucial role in stabilizing the shoulder joint and allows for external rotation of the arm. In addition to its primary functions, the infraspinatus works alongside other rotator cuff muscles, such as the supraspinatus, teres minor, and subscapularis, to provide overall shoulder stability. Injuries to the infraspinatus can lead to pain and limited mobility, affecting daily activities and sports performance.