The effect of weight on the femur: a cross-sectional analysis.

This study assessed whether obesity significantly affects femoral shape. Femora of 121 white men were divided into two weight classes based on body mass index (BMI) of the deceased. Five external anteroposterior (AP) and mediolateral (ML) measurements were taken at consistent percentages of diaphyseal length. These were then subject to statistical tests. After controlling for age, multivariate statistics show a significant (p<0.05) effect of BMI on the femur, with the greatest significance in ML measurements. T-tests confirm these dimensions are significantly larger in the overweight (p<0.05). The effect of BMI on size-transformed and shape-transformed variables was also evaluated, with ANOVA results showing a significant BMI effect on ML size (p<0.05), but not shape. Significant size-transformed ML variables were then subject to discriminate function analyses with a cross-validation correction. Results show a correct classification rate of 88% in normal weight and 77% in overweight individuals.