These conditions are caused by injuries to the muscles in the forearms, which work the fingers. The injury is caused by the muscles being caused to overstretch rapidly or by repeated overstretching. The pain from the injury is felt at the bony parts at the inside and outside of the elbow and is usually quite acute. The person with the injury is often surprised when the therapist works on the forearm and not the elbow. Although painful these injuries respond well to massage and athletes can be taught to self-massage between visits to the therapist.