Biomechanical differences of Asian knee osteoarthritis patients during standing and walking using statistical parametric mapping: A cross-sectional study

Abstract

Background: Biomechanics of knee osteoarthritis (KOA) patients have been extensively studied using motion capture systems, but less have explored standing knee joint angles with the walking parameters, particularly in Asians. We aim to determine gait biomechanical differences between healthy and KOA participants in an Asian population using One-dimensional Statistical Parametric Mapping (SPM1D) and explore if they are associated with standing joint angles. Methods: A total of 20 KOA and 24 healthy stood upright and walked 10 m at self-selected speeds. The standing angles, walking kinematic and kinetic parameters of the ankle, knee, hip and trunk were analysed. Lower limb muscle excitation was measured via electromyography. SPM1D was used to compare the healthy group with the KOA group, and for further subgroup analysis. Results: The all KOA group had significantly greater standing knee flexion angles (KFA) (p < 0.001), standing ankle dorsiflexion angles (ADA) (p < 0.001), walking KFA during terminal stance (p = 0.001) and terminal swing (p = 0.02) and walking ADA during terminal stance (p = 0.02) and mid-swing to terminal swing (p = 0.001). Knee adduction moment (p = 0.04) and knee flexion moment (p = 0.03) were higher in severe KOA. A positive correlation was found between standing KFA and initial KFA (R2 = 0.579), and mean walking KFA (R2 = 0.801) in the KOA group. Conclusion: The increase in standing KFA was associated with an increase in walking KFA in the KOA group. Static joint angles remain as an essential parameter, although further studies need to be carried out to determine if the increase in standing joint angles can be recommended as an adjunctive measure during gait analysis of KOA using motion capture.