Surface replacement arthroplasty of the proximal interphalangeal joint using the SR PIP implant: long-term results.

PURPOSE: To evaluate the long-term results of proximal interphalangeal (PIP) joint surface replacement arthroplasty for arthritis using the SR PIP implant (Small Bone Innovations, New York, NY).

METHODS

This is a long-term retrospective analysis of results in 39 of 43 joints first reported in 2008. Subjective results were based upon a mailed questionnaire. Active range of motion was measured by a certified hand therapist, and x-rays were obtained to analyze changes occurring since the first study.

RESULTS

The average follow-up time was 9.3 years. The average active PIP joint arc of motion in the present cohort of patients went from 64° at the first report (2008) to 56° at this time. Radiographic comparisons revealed no major changes since the first study. Ten of 11 revisions were done for pain due to loosening and were performed at an average of 20 months after the primary procedure. No further revisions were necessary in the interim. Overall, subjective measures of satisfaction and symptomatic and functional improvement remained unchanged.

CONCLUSIONS

Surface replacement arthroplasty using the SR PIP implant continues to be an option for patients with osteoarthritis of the PIP joint. Long-term subjective and objective outcomes are comparable to those reported using other implants. This and other studies suggest that this procedure is not appropriate for most rheumatoid joints. In the interim between studies, we saw a reduction in the average PIP joint arc of motion, although this change did not reach statistical significance. Our original revision incidence of 26% has not changed. Subjective evaluation and radiologic findings did not change between studies.

TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.