What Root, an orthopedic surgeon who specializes in sports injuries has to say about the care and treatment of tennis elbows, trick knees and golfer's hips is usually very simple: rest, improved playing technique and some regular strengthening exercises for the musculature around the affected joint is generally all that's needed. For each injury discussed Root gives a detailed -- excessively detailed -- anatomical explanation of muscles, nerves, bones, tendons, ligaments and cartilages and how they interact when you perform one of those body contortions which sends the ball spinning out of your opponent's range. In cases of severe pain cortisone and butazolidin may be given, and sometimes -- say in the case of a torn ligament -- surgery is necessary. But even though most of these injuries are progressive and recurrent when left unattended, they can easily be prevented by building up your body to withstand the trauma of sudden forceful impacts, stretching or wrenching. Alternatively, you could take up chess.