EVALUATING KINOVEA’S VALIDITY IN MEASURING FOOT KINEMATICS ACROSS WALKING SPEEDS: A 3D MOTION CAPTURE COMPARISON

Abstract

Background: Kinovea is a free 2D motion analysis software frequently used for clinical gait analysis. However, its precision against gold-standard 3D motion capture systems, such as OptiTrack, has yet to be investigated, especially when measuring foot kinematic parameters during variable walking speeds. This study aims to establish the validity of Kinovea in measuring foot kinematic angles during walking by comparing its measurements with those of the OptiTrack 3D motion capture system.

Methods: Thirty-two healthy adults were tested while walking on a treadmill at speeds of 2, 3, and 4 km/h. Primary foot kinematic angles (medial longitudinal arch, subtalar, and first metatarsophalangeal) were measured with both Kinovea and OptiTrack. Mean differences were assessed with a paired t-test or Wilcoxon test, and agreement was examined using the Bland-Altman method.

Results: Most parameters showed no statistically significant differences at 2 and 3 km/h. However, at 4 km/h, several MLA parameters exhibited significant differences (p < 0.05). Both the bias and limits of agreement (LoA) of Kinovea were increasingly deviated away from the line of identity and became wider at higher speeds. 

Conclusion: Kinovea evidenced moderate-to-acceptable validity at slow-to-moderate speeds.