Tennis elbow is a painful condition caused by overuse of the “extensor” muscles in your arm and forearm, particularly where the tendons attach to rounded projections of bone (epicondyles) on the outside of the elbow. The muscles you use to grip, twist, and carry objects with your hand all attach to the “lateral epicondyle” at the elbow. That’s why a movement of the wrist or hand can actually cause pain in the elbow. Prolonged use of the wrist and hand, such as when using a computer or operating machinery —and, of course, playing tennis with an improper grip or technique—can lead to tennis elbow. It can happen to athletes, non-athletes, children, and adults. It occurs more often in men than women, and most commonly affects people between the ages of 30 and 50.