Long-term outcomes of proximal interphalangeal joint surface replacement arthroplasty.

BACKGROUND Surface replacement arthroplasty is a reconstructive alternative for the treatment of pain and deformity due to osteoarthritis and rheumatoid arthritis of the proximal interphalangeal joint of the finger. This retrospective study was performed to examine long-term outcomes of proximal interphalangeal joint prosthetic surface replacement with a proximal cobalt-chromium (CoCr) and distal ultra-high molecular-weight polyethylene component over thirty years at a single institution. METHODS Sixty-seven prostheses were implanted in forty-seven patients between 1974 and 2007. The mean duration of follow-up was 8.8 years. There were fifty joints (75%) with osteoarthritis and seventeen (25%) with rheumatoid arthritis. Fifty-six prostheses (84%) were implanted via a dorsal approach, forty-eight (72%) were cemented, and nineteen (28%) were press-fit. Postoperative evaluation, consisting of a clinical history and examination, radiographs, the Short Form-36 (SF-36) and Disabilities of the Arm, Shoulder and Hand (DASH) questionnaires, and a visual analog scale (VAS) pain score, was performed for thirty-six patients. Demographic, surgical, and implant failure data were obtained from the medical charts of eleven patients (sixteen implants) who had died prior to the time of postoperative follow-up. RESULTS At the time of follow-up, the median total active proximal interphalangeal joint motion was 40°. Eight prostheses had failed, yielding a cumulative incidence of implant failure of 3% at one year, 8% at three years, 11% at five years, and 16% at fifteen through twenty-five years. Prostheses implanted via a volar approach failed more often than those implanted via a dorsal approach (relative risk: 6.59, p = 0.004). The failure rate did not differ significantly between patients with rheumatoid arthritis and those with osteoarthritis (p = 0.17). The median VAS pain score at the time of follow-up was 3 (of a maximum of 100). There were twenty-two complications in fourteen patients, resulting in four interphalangeal fusions and two amputations. There were no infections. CONCLUSIONS Proximal interphalangeal surface replacement arthroplasty is a reliable treatment alternative for pain and deformity due to proximal interphalangeal joint osteoarthritis and rheumatoid arthritis. At the time of long-term follow-up, pain was minimal and joint motion was similar to preoperative levels.