Fatigue induced changes to kinematic and kinetic gait parameters following six minutes of walking in people with multiple sclerosis

Purpose: The aim of this study was to examine the effect of 6min of walking on fatigue, exertion and spatiotemporal, kinematic and kinetic gait parameters in people with multiple sclerosis (MS). Methods: Thirty-four people with MS with moderate levels of disability completed measures of fatigue, exertion and instrumented gait analysis before and after 6-min trials of rest and walking (using a modified 6-min walk test, m6MWT). Ten age- and gender-matched healthy controls completed analysis before and after the m6MWT. Results: The MS group had a significant increase in self-reported fatigue following the m6MWT; however, there was no effect on spatiotemporal gait parameters. During stance on the more affected side ankle dorsiflexion at initial contact decreased, while knee and hip flexor moments and hip power absorption increased. On the less affected side ankle and knee power absorption, and hip extensor moment all increased. Healthy controls showed increases in joint kinetics likely due to increased walking speeds following m6MWT. Conclusion: For people with MS, ankle dorsiflexion angle reduces at initial contact following walking induced fatigue, while increased power absorption at the hip, knee and ankle indicate gait inefficiencies that may contribute to higher levels of fatigue and exertion.