The rotator cuff consists of a group of four muscles that reside deep in the shoulder area beneath the bulkier upper arm muscle called the deltoid. The four muscles termed the subscapularis, supraspinatus, infraspinatus, and teres minor attach to the top portion of the arm bone called the humerus. Collectively the rotator cuff muscle group assists in the elevation and rotation of the shoulder and the integrity of the rotator cuff is essential to normal shoulder function.
Rotator cuff disorders encompass a variety of conditions, some of which involve the inflammation of the rotator cuff structures while others involve true structural damage to the cuff. In addition to rotator cuff tears, common conditions that involve the rotator cuff are subacromial or subcoracoid impingement syndrome, bursitis, tendinosis, calcific tendinitis and scapular dyskinesis.