Sensory impairments in quiet standing in subjects with multiple sclerosis

Balance disorders and falls are frequently observed in subjects with multiple sclerosis (MS). Along with motor impairment, sensory disorders and integration deficits of sensory inputs lead to inadequate motor responses. The assessment of these sensory disorders in an every day tasks, such as upright stance, increases our knowledge of postural control in this pathology, thus promoting more effective treatments. The aim of the study was to describe sensory impairments and sensory strategies in different sensory conditions. A stabilometric assessment was carried out in a consecutive convenience sample of 53 subjects. The age of the sample was 52.7 (21.1) years; the onset of pathology was 27.20 (14.5) years before the assessment. Balance was assessed in six sensory conditions. The impact of pathology on balance control was shown by the high percentage of abnormal scores: 75% of subjects with MS showed abnormal scores even in the eyes open condition. The alteration of a single sensory input led to an increase of abnormal scores in up to 82% of subjects. Almost all subjects showed abnormal scores in the vestibular conditions where 22% of them fell. The pattern of the subjects' performance in the six sensory conditions suggests that balance control may be more correlated to the number of reliable sensory inputs than the nature of the sensory input itself.