Magnetic resonance imaging as a research tool for biomechanical studies of the wrist.

The field of biomechanics has welcomed magnetic resonance imaging (MRI) as a research tool to provide quantified anatomy of various body parts in vivo. The ability to view, reconstruct, and analyze images of an intact system under varying conditions has improved our knowledge of functional anatomy. This article forms a review of MRI use in biomechanics research, with examples from several areas and an emphasis on the distal upper extremity. Biomechanical parameters such as muscle fascicle directions of pull, moment arms in three dimensions, muscle cross-sectional areas, and detailed muscle geometry data are prevalent because of advances in imaging technology. This has resulted in improved anatomic realism in biomechanical models. Wrist biomechanics research has benefited greatly using MRI. The unique anatomy of the carpal tunnel, and the concerns regarding carpal tunnel syndrome, have prompted numerous studies examining the contents of the carpal tunnel, its shape, and its volume. These studies are presented, as is an analysis of the finger flexor tendons as they pass through the carpal tunnel. These imaging-based studies all examine the aspects of the potential mechanisms for median nerve compression at the wrist. MRI is a tremendously valuable tool in biomechanics research, especially in the search for the mechanisms of carpal tunnel syndrome and wrist function, providing both visual representation and quantitative evaluation of anatomic phenomena.