There may be a partial tear of the tendon fibers at or near their point of insertion on the humerus.
Risk factors are forceful repetitive wrist or forearm movement.
The injury is associated with tennis playing. The incidence is 9 out of 10,000 people. Rest the elbow when flexion and extension is painful. The diagnosis is made by clinical signs and symptoms, since X-rays are usually normal. Tenderness over the elbow can be present.