Lower-extremity rotational problems in children. Normal values to guide management.

TLDR

In utero positioning rotates the femur laterally and tibia medially, effects that resolve in infancy revealing genetically determined individual differences, with out‑toeing, medial tibial torsion, and medial femoral torsion representing extremes of normal development. The study aimed to establish normal lower‑extremity rotational values from 1,000 specimens and to use these values to guide clinical evaluation of rotational problems. The authors measured rotational angles in 1,000 normal lower extremities from children and adults to derive reference values. Most rotational variations fall within the normal range and generally require no treatment.

Abstract

We studied 1,000 normal lower extremities of children and adults in order to establish normal values for the rotational profile. The intrauterine position of the fetus molds the femur by rotating it laterally and molds the tibia by rotating it medially. These molding effects usually resolve spontaneously during infancy, and then genetically determined individual differences are unmasked. Rotational problems should be clinically evaluated and the findings compared with the normal values provided by this study. Out-toeing in infants, medial tibial torsion in toddlers, and medial femoral torsion in young children are extremes of a normal developmental pattern. In the vast majority, these rotational variations fall within the broad range of normal and require no treatment.