Tendinitis Rotator Cuff Anatomy
To better understand rotator cuff tendinitis, it helps to understand the anatomy of the shoulder joint.
The rotator cuff is part of the shoulder joint. This joint allows motion between two major bones: the humerus and the scapula. The shoulder joint is a ball and socket joint. A depression off the scapula, known as the glenoid, provides the socket for the head of the humerus. Ligaments and muscles stabilize the joint during use.
The rotator cuff consists of four muscles and tendons that surround the top and back of the shoulder. These tendons hold the head of the humerus in the glenoid.
The rotator cuff tendon is composed of:
These four muscles normally act to raise the arm up and away from the body. This motion is called abduction.
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