The Rotator Cuff
The rotator cuff — 4 muscles connecting the humerus with the scapula — supplies stability and balance to the shoulder joint. Proper rotator cuff balance is essential for arm raising and rotation. When you raise your arm, the rotator cuff holds the humeral head tightly within the socket (glenoid) of the scapula.
Causes of Shoulder Pain:
- Tendonitis/bursitis
- Injury/instability
- Arthritis