[Total radiocarpal prosthesis. Preliminary study]

The mechanical requirements before satisfactory muscular balance in a total wrist prosthesis have been studied in 25 cadavers. The centre of rotation was determined in X-Rays; it was localised in the sagittal plane crossing the axis of the forearm and in the frontal plane situated in front of the axis of the forearm. A graphic model of the wrist was then established. A total prosthesis was then designed, made up of two components with a torus surface. This prosthesis was found to be compatible with the wrist model. Movement required forces only slightly greater than normal muscular activity. One male was operated on using this prosthesis. The result was satisfactory after one year.