The total wrist joint arthroplasty: biomechanical considerations and research directions.

A review of the state-of-the-art knowledge base on the biomechanics of the wrist joint, with emphasis on total wrist joint arthroplasty, is presented. The reasons for the reported high rate of aseptic loosening of the metacarpal component of such an implant are unknown at this time. It is suggested that detailed stress analyses of models of the joint, without and with the aforementioned implant, will yield results that will increase understanding of this problem and improve implant design, resulting in enhanced clinical performance of these replacements. For this purpose, it is recommended that the finite element analysis method be used.