The primary aim of this clinical and radiostereometric study was to study the migration pattern of the surface replacement trapeziometacarpal joint prosthesis (SR^TMTMC, Avanta^®, San Diego, CA). The secondary aims were to assess patient-related outcomes and prosthesis survival 5 years after surgery. Ten patients received the prosthesis. Radiostereometric radiographs were obtained 6 weeks, 6 months, 1 year and 5 years post-operatively and were analysed using model-based software. All patients completed DASH and Nelson Hospital scores at these follow-ups. Mean translations varied between 0.0 and 0.5 mm after 5 years. Rotation values could be calculated in six patients and mean rotations varied between –0.3 and 2.3°, although the precision of rotation values seems to be poor. The 5-year survival rate was 80%. Mean pre-operative DASH and Nelson Hospital scores were 53 (SD 14) and 51 (SD 13), respectively. Six months post-operatively, the DASH and Nelson Hospital scores had both significantly improved to 25 (SD 20) and 74 (SD 18) and remained high after 5 years. Implant stability was good 5 years post-operatively, and early migration did not predict implant failure in this study.

Level of Evidence: IV.