Shank motion analysis for quantifying knee gait deviations: Normative data at various walking speeds

BACKGROUND: Knee deviations in clinical gait analysis are often measured using joint angles and could be enhanced by incorporating additional indices such as shank angular velocity in addition to knee angular velocity, particularly in the context of knee extensor thrust. The aim of this study was to establish normative data for shank and knee angular velocities at various gait speeds and to perform clinical validation of these biomarkers. METHODS: A public dataset containing three-dimensional motion capture established on 50 healthy participants was used to calculate normative data of knee and shank angular velocities at five gait speeds (means, standard deviations and confidence intervals). Eleven hemiparetic persons walking with knee extensor thrust underwent three-dimensional gait analysis, during which minimum knee and shank angular velocities during stance phase were calculated. RESULTS: Hemiparetic persons walking with knee extensor thrust had significantly lower minimum knee and shank angular velocities than normative data at all gait speeds (P < 0.001). In healthy persons, the minimum values for knee and shank angular velocities during stance phase or the values at foot-off, like most knee kinematics parameters, were correlated with gait speed (r = -0.83; r = 0.67; r ≥ 0.9; P < 0.01). CONCLUSION: This study provides normative data for knee and shank angular velocities at various gait speeds and demonstrates their usefulness for analysing knee deviations, notably the knee extensor thrust. This study underscores the impact of walking speed on gait patterns particularly on knee and shank angular velocities and underlines the need to compare data at the same gait speed for practice and future research.