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 single physical examination test distinguishes reliably between bursitis, partial-thickness, and full-thickness tears. On the contrary, a combination of tests seems to provide the most accurate diagnosis. For impingement, these tests include the Hawkins-Kennedy impingement sign in which the examiner medially rotates the patient's flexed arm, forcing the supraspinatus tendon against the coracoacromial ligament and so producing pain if the test is positive a positive painful arc sign, and weakness in external rotation with the arm at the side. For the diagnosis of full-thickness rotator cuff tear, the best combination appears to include once more the painful arc and weakness in