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.