Gait and balance impairment in early multiple sclerosis in the absence of clinical disability

Abstract

This study evaluated the gait and balance performance of two clinically distinct groups of recently diagnosed and minimally impaired multiple sclerosis (MS) patients (Expanded Disability Status Scale range 0- 2.5), compared to control subjects. Ten MS patients with mild pyramidal signs (Pyramidal Functional Systems 1.0), 10 MS patients with no pyramidal signs (Pyramidal Functional Systems 0) and 20 age- and gender-matched control subjects were assessed using laboratory-based gait analysis and clinical balance measures. Both MS groups demonstrated reduced speed and stride length ( P < 0.001), and prolonged double limb support ( P<0.02), compared to the control group, along with alterations in the timing of ankle muscle activity, and the pattern of ankle motion during walking, which occurred independent of gait speed. The pyramidal MS group walked with reduced speed ( P=0.03) and stride length ( P=0.04), and prolonged double limb support ( P=0.01), compared to the non-pyramidal group. Both MS groups demonstrated concomitant balance impairment, performing poorly on the Functional Reach Test compared to the control group ( P<0.05). The identification of incipient gait and balance impairment in MS patients with recent disease onset suggests that motor function may begin to deteriorate in the early stages of the disease, even in the absence of clinical signs of pyramidal dysfunction.