Rotator cuff tendon at the entrance of the bicipital groove. The supraspinatus is most commonly involved in a rotator cuff tear. The rotator cuff muscles are important in shoulder movements and in maintaining glenohumeral joint (shoulder joint) stability. These muscles arise from the scapula and connect to the head of the humerus, forming a cuff at the shoulder joint. They hold the head of the humerus in the small and shallow glenoid fossa of the scapula. The glenohumeral joint has been analogously described as a golf ball (head of the humerus) sitting on a golf tee (glenoid fossa). During abduction of the
Rotator cuff tear the rotator cuff muscles become irritated and inflamed while passing through the subacromial space beneath the acromion. This relatively small space becomes even smaller when the arm is raised in a forward or upward position. Repetitive impingement can inflame the tendons and bursa, resulting in the syndrome. Well-documented anatomical factors include the morphologic characteristics of the acromion. Hooked, curved, and laterally sloping acromia are strongly associated with cuff tears and may cause tractional damage to the tendon. Conversely, flat acromia may have an insignificant involvement in cuff disease and consequently may be best treated conservatively. The development of these different