Clinico-physiological foundation of application of exoskeleton “Exoatlet” during walking of patients with disseminated sclerosis

Abstract

On the basis of investigations of the biomechanical and innervative structure of walking of patients with disseminated sclerosis, authors of this article gave foundation of application of the exoskeleton ExoAtlet in this disease. Earlier, these authors revealed that patients with disseminated sclerosis have some similar disorders, which are characteristic of all patients with diseases of the locomotor system, namely, reduction of walking, velocity, weakening of the support and push functions of the lower extremities, pronounced decrease of maxima of electrical activity of muscles during the locomotor cycle. On the example of the concrete patient, authors established that this patient has the specific peculiarities of walking, characteristic only of this disease. Authors consider that the following peculiarities of walking are specific only to patients with disseminated sclerosis: cyclic character of the vertical component of the ground reaction force Rz and electromiography-pattern of muscles, unsteadiness of gait, triangular or trapezoid shape of the vertical component Rz of the ground reaction force, equinus of the foot and the ankle joint often in combination with recurvation at the knee joint, considerable diminution of the main flexion at the knee joint in one or both lower extremities, reduction of electrical activity of muscles and its prolongation for most part of the stance phase. With the purpose of investigations of the energetic parameters of walking and revealing the resonance properties of the lower extremities in this disease, authors studied electromiography-pattern of two symmetrical muscles of the lower extremities (both mm. rectus femoris and both mm. biceps femoris) during walking at different cadences in this patient. Method of training of walking in the exoskeleton for patient with disseminated sclerosis included the total time of training, time of walking without rest, distance, which patient could walk for the session, walking velocity, cadence and double step length during walking in the exoskeleton, total number of steps for the session. Authors ascertained that considerable improvement of the biomechanical and innervative structure of walking takes place after the course of training in the exoskeleton ExoAtlet in combination with the medicines, changing the course of the disseminated sclerosis, which is revealed in increase of walking velocity, in growth of the amplitude of the angular displacements at the joints of the lower extremities, in disappearance of phenomena of cyclicity of electromiography-pattern, in change of the form of the vertical component Rz of the ground reaction force from the triangular or trapezoid to the clear-cut two peaked in parallel with increase of the extreme values of Rz curve, in growth of the maximums of activity of all muscles and their concentration in the adequate phase of the locomotor cycle, in rise of the mean electrical activity (muscle capacity) with increase of walking velocity, in appearance of two parabola branches with presence of the distinct minimum in the curve of the summary integral for distance of 10 meters.