ANCHORAGE OF WRIST JOINT PROSTHESES TO BONE USING THE OSSEOINTEGRATION PRINCIPLE

Five patients with rheumatoid arthritis (age 28-60 Sears) underwent wr ist joint arthroplasty with individually designed artificial joint mec hanisms, anchored to bone using the osseointegration principle, We rep ort on the result from a 4 to 6.5 year follow-up with special emphasis on the fixation of the prosthesis to bone. There was no bone resorpti on or loosening of screws. Osseointegration of the titanium screws occ urred in all cases and persisted throughout the observation period, al though scattered lytic zones could sometimes be seen around the screws . The clinical results were satisfactory with pain relief and maintena nce of a functional range of movement. The principle has prospects for fixation of a wrist joint mechanism to bone, although the presently u sed joint mechanism requires further refinement.