Medium to Long-Term Follow-Up After Pyrocarbon Disc Interposition Arthroplasty for Treatment of CMC Thumb Joint Arthritis

Purpose: Pyrocarbon disc interposition arthroplasty has been designed for the surgical treatment of Eaton–Glickel grade II/III carpometacarpal thumb joint arthritis. This study presents the results of this technique with a minimum 5-year follow up. Methods: We assessed 4 questionnaires for patient-reported outcome measurements in a cross-sectional study: the Patient-Rated Wrist and Hand Evaluation, Disabilities of Arm, Shoulder, and Hand questionnaire, Michigan Hand Questionnaire, and questions about satisfaction at the 5-year follow up. We evaluated grip and pinch strength, range of motion, and the radiological position of the disc. Finally, a Kaplan–Meier survival analysis was performed. Results: A total of 164 thumbs (in 137 patients) were available for follow-up varying from 5 to 12 years. Median Patient-Rated Wrist and Hand Evaluation, Disabilities of Arm, Shoulder, and Hand, and Michigan Hand Questionnaire scores were 17, 18, and 76, respectively. The satisfaction score was 9 (Likert scale of 1–10). Grip and pinch strength reached nearly 100% compared with the contralateral hand. Range of motion resulted in a Kapandji score of 10. Thumb height showed a marginal loss and the Kaplan–Meier survival curve showed a survival rate of 91%. Conclusions: Our study suggests that pyrocarbon disc interposition arthroplasty is a reliable and feasible treatment for carpometacarpal thumb joint arthritis at medium-term follow-up. It was associated with a high level of patient satisfaction; it maintained thumb height and the implant survived in 91% of patients. Strength and range of motion were comparable to the contralateral hand after a minimum follow-up of 5 years. Type of study/level of evidence: Therapeutic IV.