The technique was developed by a Los Angeles Dodgers team physician, who used it to repair a UCL injury suffered by pitcher Tommy John in 1974 by replacing the ulnar ligament with a tendon taken from elsewhere in the body. Since that pioneering procedure, experienced surgeons like skilled Chicago orthopaedic surgeon Dr. Anthony Romeo have perfected the technique. The surgery is most often used for active athletes who require full functionality of these ligaments for overhead or throwing sports.