Analysis of neuromuscular parameters in patients with multiple sclerosis and gait disorders

Gait is a motor activity that requires understanding the dynamics and functional anatomical elements that make possible its cyclical conduct. Patients with multiple sclerosis record impaired balance and gait due to the process of demyelination, disorders that can be estimated by quantifying neuromuscular and cortical parameters. The aim of this paper is to present both an analysis of these parameters in the thigh muscles and an evaluation of cortical parameters obtained by visual evoked potentials (VEP).

The study was conducted on a group of 13 patients (mean age 38 years) with multiple sclerosis (MS), who had clinically detectable gait disturbance. Evaluation methods used were tensiomyography (TMG) and VEP, the monitored parameters were: contraction time (Tc), stance time (Ts), displacement (Dm), if TMG in the two muscle groups of the thigh (biceps femoris and right femoris), and if VEP the assessed waves were N75, P100, N135-145.

There were estimated the average values of latency and duration of the three analyzed waves in VEP, the values of wave N135-145 were far higher than physiological values. In terms of TMG values, they results indicate the existence of a clear right-left functional asymmetry.

Analyzing these results, we note an increase in the muscular tone of the groups studied, a functional asymmetry agonist/antagonist, low speed response to stimulus. Regarding VEP wave parameters, we find significant variations of these waves' latencies, particularly of P100 wave, while the duration of these waves did not register significant figures. In conclusion, we can emphasize a change in muscle structure with predominantly type I muscular fibers and inter-neuronal connections between areas of the association to substitute the lesions occurred in specific areas.