Femoral anteversion in normal adults. Ultrasound measurements in 50 men and 50 women.

The femoral anteversion (AV) angles were measured by ultrasound in a normal group of 100 adult subjects to find the normal range of anteversion, to determine the normal left/right difference, to assess the interobserver variation, and to find the correlation between AV angle and clinical hip rotation. All the ultrasound measurements were performed independently by 2 observers. The mean AV angle was 18 degrees in the women and 14 degrees in the men. The mean left/right difference in AV was 3.8 degrees, and the upper normal limit of side difference (mean +/- 2 SD) was 9.8 degrees. The mean (SD) interobserver variation was only 1.9 degrees (1.3 degrees). The correlations between AV angles and internal and external hip rotation were significant, but not very high (r = 0.49 and -0.49, respectively). We conclude that ultrasound is appropriate for measurement of femoral anteversion. Our results could be used as a basis when evaluating patients with clinically suspected rotational disorders of the femur.