[Pyrocarbon prosthesis for finger interphalangeal joint replacement. Experience after one year].

The long-term results of finger joint replacement, particularly the proximal interphalangeal (PIP) joint, have mostly been disappointing according to a review of the international literature and our own experiences. The recently developed pyrolytic carbon implants (Ascension Orthopedics, Austin, Texas) for replacing the PIP joint were evaluated retrospectively regarding range of motion, functionality, and relief of pain. In our hospital 17 PIP joints were replaced with pyrolytic carbon implants in 16 patients by an offset stem technique inserted without cement. This study included 13 patients; we excluded three patients because of follow-up <3 months. Prerequisites were adequate collateral ligaments, bone stability, and sufficient or at least reconstructable extensor tendons. The purpose of this study was to evaluate the 1-year outcome (minimum 270, maximum 360 days) regarding range of motion, implant stability based on radiological and clinical parameters, and relief of pain using a pre- and postoperative visual and verbal analogue scale.There was an improved range of motion of the PIP joint from 0-28-51 preoperatively to 0-22-77 postoperatively (average value). On the visual analogue scale (0 no pain, 10 incapacitating pain) we achieved pain relief at rest and in motion of 80%. On the verbal analogue scale there was an improvement of 62%. The results of this study demonstrate that pyrolytic carbon implants reduce pain and are functionally superior to arthrodesis. A precise and individual postoperative protocol is necessary for beneficial results.