Measurement of tibial torsion and thigh-foot angle using goniometry and computed tomography

Three therapists measured tibiofibular torsion and thigh-foot angle (TFA) goniometrically in 17 normal subjects, aged three to 24 years. Tibiofibular torsion was also measured using computed tomography (CT). Differences between testers for the goniometric measures were analyzed using a nonparametric analysis of variance. Wilcoxon's rank sum test was used to determine differences between goniometric and CT measures for tibiofibular torsion. No significant difference for goniometric measures was found between testers for tibiofibular torsion or TFA. A significant difference averaging 5 degrees between goniometric and CT torsion measures was found between testers. Although a significant difference was found between the two measurement methods, the degree of difference may not represent a significant clinical difference, as a range at 5 degrees is commonly reported as the margin of error for goniometric measurements.