[True orientation of the acetabulum as determined by CAT scan. Preliminary results (author's transl)].

Valid clinical correlations with biomechanical data require three-dimensional visualization of a joint, in order to determine the true spatial configuration of the various segments of the part studied. The CAT scan has opened a new pathway in this direction, as it supplies precise mathematical information on the segments explored. An original analytical programme was employed in humans to establish the true spatial orientation of the acetabular cavity. The validity of the method was confirmed by comparing results in 31 subjects with the rare cases where such measurements were made, reported in the published literature. The method could be extended to other body regions.