Changes in dynamic balance in multiple sclerosis patients as related to the severity of disease and self-rated fatigue
Date
2005
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Publisher
University of Delaware
Abstract
Impaired balance and fatigue are two common symptoms of multiple sclerosis (MS) that can impact the everyday activities of MS patients. Maintaining balance during walking, referred to as dynamic balance, requires the legs to control the motion and position of the upper body. The purpose of the study was to determine which variables of dynamic balance were the most closely related to the severity of the patients’ MS and their fatigue level, and which of the significantly related variables were sensitive enough to detect differences between the MS patients and the control subjects. Ten MS patients and eight age-matched healthy control subjects were required to attend two testing sessions, one in the morning and one in the afternoon. The subjects were also required to rate their fatigue and perceived exertion (RPE) throughout the testing sessions. Kinematic data were collected from a minimum of six walking trials before and after a walking protocol designed to raise the subjects’ RPE and fatigue level. The relationships between the three groups of variables (temporal-spatial variables, trunk movement variables, center of gravity variables, and the standard deviations of the variables) and fatigue and disability level were determined using Pearson’s product-moment correlation coefficients (p<0.05) for MS patients. The variables that correlated with the severity of disease and fatigue level were then entered into a one-way ANOVA to determine if there was a statistical difference (p < 0.05) between the control group and the MS group. A repeated-measures ANOVA was used to determine statistical differences (p<0.05), between the groups and testing sessions for fatigue and walking speed. The temporal-spatial variables and trunk movement variables were more related to the severity of disease than the fatigue level, but the change in center of gravity variables were more related to fatigue than to the severity of disease. Two variables that were significantly related to the severity of disease or fatigue level were also found to be significantly different between the control subjects and the MS subjects: variability of the lateral center of gravity displacement between strides during the afternoon fatigue session, and the change in variability of the lateral center of gravity displacement from the afternoon fresh trials to the afternoon fatigue trials were significantly different when comparing the control subjects from the MS subjects. The lack of significant differences between MS subjects and control subjects suggested that the chosen variables were not sensitive enough to detect differences in dynamic balance between MS patients and control subject.