We hear a lot about rotator cuff injuries in baseball pitchers and football quarterbacks; since they use their rotator cuffs dramatically, they suffer dramatic injuries. But it is an extremely common source of pain in the shoulder and arm from ordinary use.

The rotator cuff consists of four muscles:

..Supraspinatus (abductor)
..Infraspinatus ( lateral rotator)
..Teres minor (lateral rotator)
..Subscapularis (medial rotator)

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