The rotator cuff holds the head of the long bone of the upper arm into the pit or groove of the shoulder. Rotator cuff syndrome is damage to the rotator cuff from any cause. This condition is one of the most common causes of shoulder pain. Tearing and inflammation of the tendons of the shoulder muscles can occur in activities requiring the arm to be moved over the head repeatedly as in tennis, swimming, and repeatedly lifting heavy items over the head.
The rotator cuff is commonly injured by trauma, and is particularly common in persons who perform repetitive overhead motions that place stress on the rotator cuff. These motions are frequently associated with muscle fatigue. Chronic inflammation or injury can cause tearing of the rotator cuff. The risk factors are more common in people over 40 years of age who participate in sports, exercise or an activity that involves repetitive arm motion over the head.