Comparison of two- and three-dimensional methods for assessment of

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orientation of the [1mtotal hip [m prosthesis. Herrlin [m-K. Pettersson-H. Selvik-G. Department of Diagnostic Radiology, University Hospital, Lund, Acta-Radiol. 1988 May-Jun. 29(3). P 357-61. A comparison of two- and three-dimensional methods for the determination of the orientation of [1mtotal hip [m prostheses was made in a group of 57 patients. The acetabular inclination and the collum-diaphyseal angle measured on a.p. projections (2-D) were adequate in most cases for assessing how vertically the prosthetic component was inserted, but in individual cases with a high degree of version these measurements could be misleading. Anteversion measured in the transverse plane (2-D) was more sensitive to errors than planar anteversion measured as a rotation around the longest diameter of the ellipsoid projection of the acetabular opening, but it gave a rough estimate of the relation of the prosthetic components. Determination of the spatial (3-D) orientation of the components provides a precise estimate of the component relations. Author-abstract.