Osteotomy for femoral anteversion. A prospective 9-year study of 52 children.

Fifty-two children with increased femoral anteversion had bilateral derotational subtrochanteric osteotomies at a mean age of 7 years. They were followed prospectively until at least 15 years of age; the mean observation time was 9 years. They were a subset of 95 children whose 2-year results were reported in 1989. The mean increase of femoral anteversion after the osteotomy was 6 degrees (0.7 degrees per year) and of the neck-shaft angle 5 degrees. The CE angle did not increase. Although we at present practice a more restrictive attitude towards operation of increased femoral anteversion, our study showed that a derotational osteotomy is effective in eliminating the intoeing gait and associated complaints, and the hip angles change only moderately during the remaining period of growth.