Outcomes of Total Wrist Arthrodesis: The background, rationale and plan for a randomised control trial comparing total wrist arthrodesis with and without the carpometacarpal joint.

Abstract

The goal of this thesis is to determine the optimal surgical method for total wrist arthrodesis (TWA), and how the carpometacarpal joint (CMCJ) should be treated in TWA. To achieve this goal, several approaches have been used.

A retrospective review of a cohort of patients who had undergone TWA was undertaken. This study demonstrated workers' compensation, presence of inflammatory arthritis and female sex to be factors predisposing patients to a poorer outcome. Common complications included soft tissue irritation from plates, pain at the iliac crest bone graft donor site and non-union of the third CMCJ.

A systematic review and meta-analysis of techniques of TWA was undertaken and analysis of union and complication prevalence was performed based on the technique of fixation used. A sub-analysis was done to examine arthrodesis of the CMCJ. High heterogeneity was observed in most studies. No differences were observed between techniques, and in TWA using plates no difference was seen with different treatment of the CMCJ.

A biomechanical study was undertaken to examine the performance of TWA plates, with and without arthrodesis of the CMCJ. Available plates were tested using a 3-D printed model representing an arthrodesed wrist, with a mobile or arthrodesed CMCJ. Cycles to failure and load at failure were significantly higher in all constructs with arthrodesis of the CMCJ. There were some differences in performance between plate types.

The rationale, design and a protocol for a randomised clinical trial is presented to evaluate the treatment of the CMCJ in TWA. TWA with arthrodesis of the CMCJ with a CMCJ bridging plate is compared to TWA without CMCJ arthrodesis with a non-CMCJ bridging plate. This study is in the recruitment phase.

Finally, a simple computer tomographic (CT) based radiographic classification for third CMCJ degeneration is proposed and tested. This classification has moderate to good inter-observer and re-test reliability. This classification will be used to assess degeneration of the CMCJ in the WAWWAM study.