An Outcomes Study of Proximal Interphalangeal Joint Silicone Implant Arthroplasty Using the Volar Approach.

BACKGROUND

Arthroplasty is performed at the proximal interphalangeal joint for the management of disabling osteoarthritis. This prospective cohort study evaluated outcomes of the silicone implant for the proximal interphalangeal joint using the volar approach. The authors hypothesize that the volar approach without extensor mechanism disruption will provide improved motion and maintain joint extension.

METHODS

Consecutive candidates for proximal interphalangeal joint silicone implant arthroplasty using the volar approach were evaluated. The Michigan Hand Outcomes Questionnaire and functional measurements, including grip/pinch strength and arc of motion, were administered preoperatively and at 6 weeks and 3, 6, and 12 months postoperatively.

RESULTS

Twenty-eight patients (35 joints) were included in the study. Eighteen patients (24 joints) were followed to 1 year postoperatively, with an entire cohort average of 10-month follow-up. Nineteen patients were white women, and the mean age was 64 years. The authors' hypothesis was supported by the results showing a mean gain in arc of motion of 7 degrees and a mean 5-degree extension lag improvement at 1 year. The mean postoperative arc of motion was 53 degrees with a 10-degree average extension lag. The median Michigan Hand Outcomes Questionnaire pain score improved from 70 (60 to 80) to 28 (5 to 45); scores also improved for each of the questionnaire domains. Median grip strength was unchanged.

CONCLUSIONS

The volar approach to proximal interphalangeal joint arthroplasty is technically challenging but facilitates early aggressive rehabilitation. This is critical for providing improved flexion, especially in the ulnar digits without worsening extension lag.

CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.