Background: Individuals with Multiple Sclerosis (iMS) have increased postural sway and are at higher risk for falls. Some iMS describe using light touch to enhance their balance. It is not known if light touch on a walker reduces postural sway in iMS. Light touch, referred to as haptic input, may reduce postural sway in other neurological conditions. Here we report the preliminary results from a larger study exploring the effects of haptic input on standing and walking balance in iMS.
Objectives: To compare the effects of postural sway in standing with no walker (NW), with light touch on a four-wheeled walker (4WW), and with weight through a 4WW in iMS and controls.
Methods: This study was a repeated-measures randomized control design for the three aforementioned conditions. Inclusion criteria for iMS were clinically definite MS and able to stand without a gait aid. Control participants were age and sex matched to iMS and could not have a condition affecting balance. Baseline demographics included sex, age, disease duration, and self-reported falls. Main outcome was change in postural sway for each condition as measured by acceleration of path length and velocity. Postural sway was recorded for 30 seconds while standing for each condition in a random order using the Mobility Lab, APDM Inc. Condition effects were examined within or across groups using Friedmans ANOVA and group differences (iMS and controls) were examined with non-parametric Mann-Whitney U test. Significance was set at ?=.003 to accommodate multiple comparisons.
Results: Of the 28 iMS recruited, 13 (46%) were female, mean age 52 (±10.2) years (y), and mean disease duration from onset 11y (±8.8). Of the 14 controls, 7 were female and the mean age was 47y (±10.7). For the primary outcome, total path length was reduced with light touch on a 4WW (p<.001) and with weight through a 4WW (p<.001) compared to NW for iMS. Total Path length was greater in iMS compared to controls for the NW condition only (p=.001). Total path length was not significantly different for controls between conditions (p=.004). Velocity decreased with light touch on a 4WW (p<.001) and with weight through a 4WW (p<.001) conditions compared to NW in both iMS and controls. Conclusions: Postural sway is significantly reduced with either light touch or with weight through a 4WW compared to no walker in iMS. When using a walker, even with just light touch, postural sway in iMS was comparable to controls. The potential for haptic input to improve balance and reduce falls in iMS warrants further research.