Factors related to improvement of excessive femoral antetorsion of the hips in children

Abstract

© 2018, Medical Association of Thailand. All rights reserved. Background: In most patients with excessive femoral antetorsion, the condition is self-limiting and follows a benign clinical course. However, when the condition persists into adulthood, it can cause many problems. Objective: This study aimed to identify factors associated with improvement of excessive femoral antetorsion. Materials and Methods: A retrospective study was conducted of patients aged 3 to 5 years old who presented with intoeing gait due to excessive femoral antetorsion between 1 January 2007 and 31 December 2016. Medical charts were reviewed for age, gender, weight, height, body mass index [BMI], rotational profiles, Beighton hypermobility score, and treatment modalities. Univariate and multivariate logistic regression analysis were used to evaluate the association of factors potentially related to internal rotation of the hips. Results: Sixty-three patients aged 3 to 5 years old who presented with intoeing gait due to excessive femoral antetorsion were retrospectively evaluated. Mean age at first visit was 3.5±0.5 years. At the first visit, the average internal rotation of the left and right hips at first visit were 76.5±8.8 and 75.2±9.7 degrees, respectively. The mean age at last follow-up was 5.4±1.0 years, at which time the average internal rotation of the left and right hips were 68.2±7.5 and 68.2±7.5 degrees, respectively. Internal rotation of the hips tended to decrease according to time. Univariate analysis found that age, gender, and body weight were significantly related to internal rotation of the hip. In a multivariate model, increased body weight was found to be correlated with significantly decreased internal rotation of both hips. On average, females tended to have more internal rotation of the right hip than the left hip. Conclusion: Internal rotation of the hips tends to decrease according to time. Choice of treatment has no significant effect on femoral antetorsion improvement. Higher body weight is related to lower internal rotation of the hips, while females tend to have more internal rotation ofthe right hip.