Thumb Carpometacarpal Joint Arthroscopy: A Classification System and Rationale for Treatment

Osteoarthritis of the thumb basal joint is a very common and disabling condition. Arthroscopic assessment of the first carpometacarpal joint allows easy identification and classification of joint pathology with minimal morbidity. The arthritis can then be managed either arthroscopically or via an open procedure. Different procedures have been described to treat different stages of this disease. The senior author (A.B.) recently has described an arthroscopic staging system to determine treatment for basal joint osteoarthritis. Arthroscopic stage I patients can be managed with arthroscopic synovectomy and, occasionally, thermal capsulorraphy. Arthroscopic stage II patients require an extension–abduction closing wedge osteotomy that redirects the axial loads in this joint. Arthroscopic stage III patients can be treated by interposition procedures, joint replacement, or arthrodesis depending on the patient’s requirement and surgeon’s preference.