Long-term follow-up of pyrolytic carbon metacarpophalangeal implants.

Background: The metacarpophalangeal joint is the most commonly involved joint when rheumatoid arthritis affects the hand. Many prosthetic implants have been designed for the replacement of this joint. Although studies of these implants have shown relief of pain, they have generally demonstrated a poor range of motion, progression of ulnar drift, and bone loss, as well as failure, fracture, and dislocation of the implant.