Thumb Interphalangeal Joint Arthroplasty With a Surface Replacing Implant: Two-Year Results

Abstract

The aim of this study was to evaluate the 2-year clinical and patient-reported outcomes of thumb interphalangeal (IP) joint arthroplasty. In this prospective pilot study, we included patients who received a surface replacing implant at the thumb IP joint. Patients rated their pain at rest on a numeric rating scale (0-10) and completed the brief Michigan Hand Outcomes Questionnaire. The range of motion of the IP joint was also measured. If the patient acceptable symptom state was inadequate (i.e., pain at rest ≤ 1.5), the reasons for the remaining symptoms were descriptively presented. Of the 13 patients who underwent arthroplasty, 1 withdrew participation and 1 was considered for arthrodesis because of a dislocated implant. Therefore, the study included 11 patients with a median age of 67 years. The median pain at rest decreased from 6 preoperatively to 0 at 2 years, and the preoperative brief Michigan Hand Outcomes Questionnaire score increased from 38 to 58 at follow-up. The total range of motion of the IP joint was 45° at 2 years. Patient acceptable symptom state was not achieved in 4 patients including a heavy manual worker and a patient with severe systemic lupus erythematosus. Based on the inconsistency of the results, we conclude that thumb IP joint arthroplasty with a surface replacing implant is rarely indicated; it could be an alternative in patients who place great importance on precision tasks. For patients who either have high demands for a powerful pinch grip, the high physical demands of a manual job, or rheumatoid disease, IP joint arthrodesis should be preferred. Therapeutic IV.