Anatomic and kinematic analysis of the human forearm using high-speed computed tomography

A new technique using computerised tomographic images was investi gated that allows a noninvasive description of the anatomy and kinematics of the human musculoskeletal system. These images were generated by the Dynamic Spatial Reconstructor, a high-speed CT scanner, with the ability to simultaneously scan multiple thin slices. Pronation/supination in a cadaveric forearn was used as the model for investigation. Three-dimensional shaded surface displays of the bony forearm were generated. These images are dimensionally accurate and allow the superposition of the results of mathematical modelling on the image for visual examination. The spatial location of bony markers was measured and calculated screw axis data superimposed on a computer generated surface display of the forearm skeleton. Applications of the technique include anatomic measurements not easily made with other systems, such as radial-ulnar interosseous distance as a function of forearm rotation and length and the amount of forearm rotation possible at various levels of forearm lengths.