Problematic bone fixation with pyrocarbon implants in proximal interphalangeal joint replacement: short-term results.

Seventeen pyrocarbon PIP prostheses were implanted into 14 patients, followed prospectively and reviewed clinically. The patients were assessed after a mean follow-up of 20.5 months subjectively by a VAS pain scale and radiographically. Significant pain relief was noted in all patients from a mean of 7.6 pre-operatively to 1.3 at final follow-up. Migration of one, or both, components was observed radiographically in eight joints and radiolucent lines were evident in three more cases. The clinical results of the implants which had migrated were less favourable for range of motion and grip strength than the stable joints of this series, although, statistically, the results were not significant. The number of possibly unstable prostheses in this series raises the question as to whether pyrocarbon is suitable for uncemented pressfit fixation in combination with early functional rehabilitation.