Relation of femoral to tibial torsion in children measured by ultrasound.

To study the relation between femoral and tibial torsion, we measured their values by ultrasound (US) in 97 normal children in two groups (aged 6 and 15 years). Anteversion was measured between the anterior aspect of the femoral neck and the axis of the femoral condyles, and tibial torsion as the difference of the proximal to the distal posterior tibial planes. The mean value of anteversion was 37 degrees in the younger group and 24 degrees in the older group. The mean value of tibial torsion was 18 degrees in both groups. We found neither side- nor sex-dependent differences in both age groups. There was no relation between both values.