Outcome of proximal interphalangeal joint replacement with pyrocarbon implants: a long-term longitudinal follow-up study.

Introduction: The aim of this study was to compare the short-, mid-, and long-term results of pyrocarbon PIPJ arthroplasty.

Materials And Methods: Twenty-seven consecutive patients (9 males, 18 females) had arthroplasty for 32 pyrocarbon PIPJ prostheses. Two patients (two joints) were lost for follow-up. Four implants were removed during follow-up. Fifteen patients (18 implants) were available for a long-term follow-up assessment on average 9.7 (9-10.8) years postoperatively and seven patients with eight implants had telephone interviews to calculate the implant survival and complications. Of the 15 patients who came to the latest follow-up, 12 (14 implants) passed each of the three follow-up visits for short-term (ø 19 months), mid-term (ø 54 months), and long-term follow-up (ø 9.8 years) to compare functional and radiological parameters longitudinally.

Results: In total, seven of the 30 joints (23%) required a revision surgery, all within the first 2 years postoperatively, including three arthrodesis due to early infection or dislocation, and one distal component removal due to primary loosening. Three patients required soft tissue revisions. The implant survival after 9 years was 87%. There was minimal pain at rest throughout the 9-year follow-up analysis; pain with activity was rated 1.9 at the short-term assessment, 1.5 at mid-term, and 1.6 at long-term. The average active range of motion was at short-, mid-, and long-term examination 49°, 50°, and 48° and grip strength averaged 24, 24, and 21 kg, respectively. The DASH score was stable with 35, 36, and 33 points. At the long-term follow-up, all evaluated implants showed radiological signs of implant loosening or migration. According to the PIP joint outcome score, 57% resulted finally in a "good" outcome.

Conclusions: Pyrocarbon PIPJ arthroplasty has a risk of early complications necessitating revision surgeries. In spite of radiological implant migration, good pain relief, grip strength, and high quality-of-life ratings are stable for a long time.