WALKING CHALLENGES IN MODERATE KNEE OSTEOARTHRITIS: A BIOMECHANICAL RESPONSE TO MEDIAL WALKWAY SURFACE PERTURBATIONS

Abstract

Knee osteoarthritis (OA) causes debilitations to mobility. It has been hypothesized that individuals walk with altered biomechanics to prevent symptoms of instability. Perturbations can be used to investigate how individuals respond to gait challenges. The purpose is to determine if gait is altered after medial perturbations in moderate OA and asymptomatic groups. Two groups of 12 participants walked barefoot on a dual-belt instrumented treadmill at self-selected speeds. Motions, ground reaction forces and moments were recorded. Participants experienced 12 unexpected medial, 1cm/3cm perturbations during stance on each leg. Motions and moments were calculated using Cardan/Euler rotations and inverse dynamics. Repeated measures ANOVA identified differences in gait metrics, using Bonferonni’s correction for multiple comparisons. Immediately after perturbations both groups demonstrate quicker step times, wider step widths, more knee flexion at initial contact, less sagittal hip range and less dynamic flexion-extension moments. Results demonstrated both groups briefly alter walking patterns after medial perturbations.