by dr kalman piper
The Shoulder Joint
The Labrum and Biceps Tendon
The Rotator Cuff
The tendon at the top of the humeral head is called the supraspinatus tendon. Its action rotates the humeral head and causes elevation of the arm above the head. Similarly, the tendon at the front of the shoulder (subscapularis) internally rotates the humeral head and moves the arm behind the body, for tasks such as tucking in a shirt at the back or doing up a bra strap. There are two tendons (infraspinatus and Teres minor) that attach to the back of the humeral head and externally rotate the humeral head. This action is particularly important flor activities such as drinking from a cup, holding a telephone against your ear or brushing your hair.
Rotator cuff tears are very common. The supraspinatus tendon is the most commonly torn tendon. Isolated tears of the other tendons are uncommon, but commonly occur in association with tears of supraspinatus. The long head of biceps tendon is also frequently involved in rotator cuff tears.