Alternative reliable techniques in femoral torsion measurement.

The clinical and conventional bi-planar determinations of femoral torsion were compared with the tomographic technique, the reliability of which was confirmed. Femoral torsions were measured with the trochanteric prominence angle test, the sinus-wave bi-planar conventional radiographic technique, the modified Hermann bi-planar conventional radiographic technique and the limited three-dimensional volumetric tomography technique in 34 femora of 17 patients. There was a strong correlation between the modified Hermann and the limited tomography techniques for 14 intact and 20 fractured femora. If limited three-dimensional volumetric tomography cannot be obtained, the modified Hermann bi-planar conventional radiographic technique must be used in patients who have scarring about the proximal femur and obesity. Otherwise use of the trochanteric prominence angle test is much more cost-effective and is as accurate as the limited three-dimensional volumetric tomography technique.