Rotator cuff tears may be caused by an injury due to a fall or lifting a heavy object. However, many tears are the result of tendon degeneration over time, which occur with wear and age. People who do overhead activities and repetitive lifting, like painters and carpenters, are at risk for rotator cuff tears. Athletes, especially baseball and tennis players, are also at greater risk.
The shoulder joint is a ball and socket that connects the upper arm to the body. The rotator cuff is a group of four muscles that come together as tendons to hold the arm bone (humerus) into the shoulder socket (glenoid). Together, they form the rotator cuff and enable your arm to lift and rotate in different directions. When one or more of the rotator cuff tendons is torn, the tendon, or part of the tendon, no longer fully attaches to the bone. This can begin as minor fraying, or turn into a partial tear, and can lead to a complete tendon tear.