Differences in hip torque ratios between individuals with femoroacetabular impingement syndrome and asymptomatic individuals: A cross-sectional study

Abstract

BackgroundHip torque ratios are considered a useful measure for patients with hip pain. However, evidence regarding this measure for patients with femoroacetabular impingement syndrome is scarce. The primary aim of this study was to compare hip external-internal rotation and abduction-adduction torque ratios between patients with femoroacetabular impingement syndrome and asymptomatic individuals. The secondary aim was to compare hip torque ratios between the asymptomatic group and femoroacetabular impingement syndrome patients grouped according to the severity of symptoms and functional limitations. MethodsHip abduction-adduction and external-internal rotation torque ratios of 134 individuals with femoroacetabular impingement syndrome and 134 asymptomatic matched controls was assessed through isokinetic testing. Severity of symptoms and functional limitations was assessed through the iHOT-33. Mann Whitney U and Kruskall-Wallis tests were used to compare hip torque ratios between asymptomatic individuals and patients with femoroacetabular impingement syndrome and to patients with femoroacetabular impingement syndrome with different severities of symptoms and functional limitations. FindingsNo differences were identified in hip abduction-adduction (U = 7659.5, p = 0.192) and external-internal rotation (U = 8787.5, p = 0.764) torque ratios between patients with femoroacetabular impingement syndrome and asymptomatic individuals. Hip abduction-adduction torque ratio was higher (p = 0.0127) in patients with a severe state (median = 1.80, IQR = 0.61) when compared to asymptomatic individuals (median = 1.52, IQR = 0.45) (moderate effect size, r = 0.45). InterpretationPatients with severe symptoms and functional limitations related to FAI syndrome presented greater hip abduction-adduction torque ratio than asymptomatic individuals, suggesting a decreased adduction torque capacity relative to abduction torque in this subgroup of femoroacetabular impingement.