The rotator cuff is the common tendon, which attaches the four muscles that allow the shoulder to rotate and stabilize. These muscles are the Subscapularis, Infraspinatus, Teres Minor, and the Supraspinatus. These four muscles are located on both sides of the shoulder blade (Scapula) and form a cuff around the head of humerous. This cuff allows the shoulder to rotate and also keeps the humerous from coming out of the socket by stabilizing it.

The rotator cuff is important in slowing down the accelerating arm and shoulder stabilization during overhead movement. This slowing down produces tremendous forces within the shoulder and in some cases can actually be damaging to the muscle and tendons fibers. This damage begins as microscopic tears, which can spread to partial or full tears with repetitive trauma.

Tears are characterized by the inability to lift the arm, localized shoulder pain or radiating pain down the arm and pain when sleeping on the shoulder.

Repeated overhead activities, such as, throwing, racquet sports, swimming, etc; can cause tears in the rotator cuff. Tears can also be caused from shoulder impingement or acute trauma to the shoulder.

As with any injury, if you think that you might have a rotator cuff tear or are experiencing shoulder pain, you should see your doctor for a complete diagnosis. You should avoid overhead activities; they could make a tear worse.

The rotator cuff is very important to stabilize the shoulder. Even if your shoulders are pain and injury free, you should still strengthen the rotator cuff muscles at least once a week, especially if you are over 35 years old. See our Exercise of the Month for rotator cuff exercises.