Backward Walking and Dual-Task Assessment Improve Identification of Gait Impairments and Fall Risk in Individuals with MS

Abstract

Background. Individuals with multiple sclerosis (MS) experience deficits in motor and cognitive domains, resulting in impairment in dual-task walking ability. The goal of this study was to compare performance of forward walking and backward walking in single- and dual-task conditions in persons with MS to age- and sex-matched healthy controls. We also examined relationships between forward and backward walking to cognitive function, balance, and retrospective fall reports. Methods. All measures were collected in a single session. A 2×2×2 mixed model ANOVA was used to compare differences in forward and backward walking in single- and dual-task conditions between MS and healthy controls. Spearman correlations were used to examine relationships between gait and cognitive function, falls, and balance. Results. Eighteen individuals with relapsing-remitting MS and 14 age- and sex-matched healthy controls participated. Backward walking velocity revealed significant differences between groups for both single-task (p=0.015) and dual-task (p=0.014) conditions. Persons with MS demonstrated significant differences between single- and dual-task forward and backward walking velocities (p=0.023; p=0.004), whereas this difference was only apparent in the backward walking condition for healthy controls (p=0.004). In persons with MS, there were significant differences in double support time between single- and dual-task conditions in both backward (p<0.001) and forward (p=0.001) directions. More falls at six months were significantly associated with shorter backward dual-task stride length (r=−0.490; p=0.046) and slower velocity (r=−0.483; p=0.050). Conclusion. Differences in MS and age- and sex-matched healthy controls are more pronounced during backward compared to forward walking under single- and dual-task conditions. Future work with a larger sample size is needed to validate the clinical utility of backward walking and dual-task assessments and mitigate the limited sensitivity of the current dual-task assessments that primarily rely upon forward walking.