Stronger pinch strength at long-term follow-up after pyrocarbon disc interposition arthroplasty compared to trapeziectomy with ligament reconstruction and tendon interposition for CMC-1 osteoarthritis.

Abstract

In this study, we wanted to compare the pyrocarbon disc interposition arthroplasty (PDI) with trapeziectomy plus ligament reconstruction tendon interposition (LRTI). Primarily, we tested whether PDI resulted in a higher pinch strength. Secondarily, we compared the grip strength, range of motion (ROM), patient reported outcomes, satisfaction and complications. Due to scarcity of preoperative hand measurements, we performed a descriptional cross-sectional cohort study of patients operated between 2006 and 2014, with a minimum of 5 years of follow-up. Patients were treated with PDI or LRTI. We determined key pinch strength as primary outcome, followed by tip- and tripod pinch, grip strength, palmar abduction and opposition; the Michigan Hand Outcome Questionnaire (MHQ), Patient Reported hand and Wrist evaluation (PRWHE), satisfaction and complications. Propensity score matching was used to match both 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. The PDI-group patients showed stronger key and tip pinch strength than the LRTI group (p=0.027 and p=0.036 respectively). Tripod pinch, grip strength and ROM were equal for both groups. MHQ and PRWHE were comparable, with higher satisfaction for the PDI group. Eight PDI patients were converted to LRTI due to pain. This study confirmed our hypothesis that key and tip pinch strength is stronger after PDI compared to LRTI for CMC-1 joint osteoarthritis. Both techniques have comparable outcomes considering patient reported outcome (MHQ and PRWHE), ROM and complications.