Most of the time, pain over a particular area of the elbow is caused by injury to the muscles, tendons, or ligaments in that area. Using the arm over and over in the same way can cause small tears to these structures. Sometimes a nerve can get trapped between the bone and the tendon or muscle, and this can also cause painful symptoms.
The first step is to get a medical evaluation. The doctor will take a careful history and examine the arm. X-rays or other scanning technology may be used to look inside the elbow. This will help determine the cause of the elbow problem. Treatment is decided by what causes the problem. If there are no broken bones or torn tendons, the physician will most likely send your son to a physical therapist.
The physical therapist will use various treatments to reduce the painful symptoms. Once the painful symptoms are gone, a program of specific exercises will be prescribed. The therapist can also work with your son and his coach to identify any factors causing this problem. In this way, future injuries can be avoided.