Results of Pyrocarbon Disc Interposition Compared to Trapeziectomy with Ligament Reconstruction and Tendon Interposition

Background: To compare pyrocarbon disc interposition arthroplasty (PDI) with trapeziectomy plus ligament reconstruction tendon interposition (LRTI), the authors assessed whether PDI resulted in a higher pinch strength, and compared grip strength, range of motion (ROM), patient-reported outcomes, satisfaction, and complications between the approaches. Methods: Because of scarcity of preoperative hand measurements, the authors performed a descriptional cross-sectional cohort study of patients operated on between 2006 and 2014, with a minimum of 5 years of follow-up. Patients were treated with PDI or LRTI. The authors determined key pinch strength as the primary outcome, followed by tip and tripod pinch, grip strength, palmar abduction and opposition, Michigan Hand Outcomes Questionnaire (MHQ) and Patient-Reported Hand and Wrist Evaluation (PRWHE) scores, satisfaction level, and complications. Propensity score matching was used to match the study groups on demographic variables. A ratio of 2:1 was used, resulting in inclusion of 62 (of 154) PDI and 31 (of 31) LRTI thumbs. Results: Patients in the PDI group showed stronger key and tip pinch strength than did patients in the LRTI group (P = 0.027 and P = 0.036, respectively). Tripod pinch, grip strength, and ROM were equal between the groups. MHQ and PRWHE were comparable, with higher satisfaction levels in the PDI group. Eight patients with PDI were converted to LRTI because of pain. Conclusions: This study confirmed the hypothesis that key and tip pinch strength is stronger after PDI compared with LRTI for first carpometacarpal joint osteoarthritis. Both techniques have comparable outcomes considering patient-reported outcome (MHQ and PRWHE), ROM, and complications.