Practical considerations in the use of computed tomography in the measurement of femoral anteversion.

A new technique is presented for measuring femoral anteversion by computed tomography, which has advantages over earlier techniques. Computed tomography allows the visual portrayal of the cervical axis to be superimposed on the diacondylar axis for direct goniometric measurement of the anteversion angle. In addition to being accurate, the procedure requires no complicated positioning framework and can be done in a brief span of time. Clinical experience with 111 hips in 56 patients has produced accurate data, particularly with regard to congenital dislocation of the hip and Legg-Calvé-Perthes disease.