New method of studying joint kinematics from three-dimensional reconstructions of MRI data.

A new method of measuring the kinematic parameters of joints has been developed. This article describes the procedure, using tarsal joints as examples. The method uses the technique of computerized three-dimensional reconstruction from magnetic resonance images, taken at regular intervals throughout a foot's range of motion. From these reconstructions, various kinematic information, such as orientation of instantaneous axes, amounts of rotation, amounts and direction of translation, and bony contact areas, is derived. The method is noninvasive and can be applied to individual subjects or patients.