closed loop electrical muscle stimulation in spinal cord injured rehabilitation

The effect of motor training using closed loop controlled Functional Electrical Stimulation (FES) on motor performance was studied in 5 spinal cord injured (SCI) volunteers. The subjects trained 2 to 3 times a week during 2 months on a newly developed rehabilitation robot (MotionMaker™). The FES induced muscle force could be adequately adjusted throughout the programmed exercises by the way of a closed loop control of the stimulation currents. The software of the MotionMaker™ allowed spasms to be detected accurately and managed in a way to prevent any harm to the SCI persons. Subjects with incomplete SCI reported an increased proprioceptive awareness for motion and were able to achieve a better voluntary activation of their leg muscles during controlled FES. At the end of the training, the voluntary force of the 4 incomplete SCI patients was found increased by 388% on their most affected leg and by 193% on the other leg. Active mobilisation with controlled FES seems to be effective in improving motor function in SCI persons by increasing the sensory input to neuronal circuits involved in motor control as well as by increasing muscle strength

Entraînement moteur des membres inférieurs de sujets paraplégiques à l’aide d’un robot de rééducation – une étude pilote

Le MotionMaker™ est un robot de rééducation neuromotrice pour les membres inférieurs qui comporte deux orthèses motorisées avec 3 degrés de liberté (hanche, genou et cheville) et un système de stimulation électrique fonctionnelle (FES). Des capteurs de position et de moments de force montés sur chaque articulation permettent de gérer le déroulement d’un mouvement prédéterminé en ajustant en temps réel la FES et l’intervention des moteurs (assistance ou résistance) par des boucles de rétroaction

Clinical Trials with the WalkTrainer: Preliminary Results

Robotic devices are well suited for providing motion to the patient and information (positions, forces, etc.) to the therapist. The FSC and LSRO are combining their effort in the development of robotic re-education devices, focusing on active rehabilitation. A new generation of rehabilitation devices combining mobility, closed loop functional electrical muscle stimulation through force feedback and a compliant mechanical interaction was elaborated. At this time, two devices are developed: the MotionMaker™; a stationary device for functional muscle strengthening and the WalkTrainer™; the mobile rehabilitation device used for this study. Previous clinical results on the MotionMaker™ have demonstrated the enhancement of such concept to paraplegic’s life quality and muscle force increasing. The first clinical trials of the WalkTrainer™ on a population of SCI patients will be presented. These trials are made at the Clinique Romande de Réadaptation (CRR) in Sion with the help of medical actors through a predefined protocol

The WalkTrainer: A Robotic System for Walking Rehabilitation

Standard reeducation methods for paraplegic people rely on manual or robotic mobilization on a treadmill. However in both cases the motion is generated by an exterior force, the training is thus called passive. In this context the Swiss Fondation for Cyberthoses (FSC) has decided to combine the advantages of robotics (precise and repeatable motion, unlimited training) with closed-loop muscle stimulation. Thus the motion is provided by the muscle of the patients and the robot assists the subject

The WalkTrainer, a New Generation of Walking Reeducation Device Combining Orthoses and Muscle Stimulation

This paper presents a novel reeducation device for paraplegics that combines hybrid orthoses and closed-loop electrical muscle stimulation. Based on the so called Cyberthosis concept, the WalkTrainer enables an active muscular participation of the subject in the walking reeducation process by the mean of closed-loop muscle stimulation. The WalkTrainer is also equipped with a leg and pelvic orthosis, an active bodyweight support and motorized wheels to allow true over ground deambulation. This paper will focus on the development of the WalkTrainer, the presentation of the control strategies and also give some preliminary results of the first clinical trials

Pelvic motion measurement during over ground walking, analysis and implementation on the WalkTrainer reeducation device

Pelvic motions are of great importance while walking, and have thus to be taken into account when developing and controlling rehabilitation devices. This paper will first introduce a new reeducation devices for paraplegic people: the WalkTrainer. This device is composed of a leg and pelvic orthosis, an active bodyweight support and closed loop muscle stimulation. Second, the six degrees of freedom (DOF) of the pelvis will be measured by using the WalkTrainer on a population of twenty healthy subjects. Each DOF was successfully measured and can be analyzed as a function of time or gait cycle. Third several models that predict the pelvic motion amplitude as a function of various parameters (speed, size, …) will be proposed and analyzed. Fourth, pelvic trajectories will be programmed on the WalkTrainer and applied on healthy subjects by the mean of the pelvic orthosis. In that phase one of the previously proposed models will be implemented. A force reduction of 20% is measured on the pelvic orthosis when the pelvic motion amplitude prediction model is used

Conception de dispositifs de rééducation motrice et d’assistance à la marche associant orthèse et électromyostimulation transcutanée rétrocontrôlée (Cyberthèse).

En rééducation motrice il est essentiel de travailler un mouvement ou un ensemble de mouvements de manière précise et aussi physiologique que possible. Pour la rééducation de la marche, cette exigence est à l’origine de méthodes d’entraînement sur tapis roulant. La mise en oeuvre de cette technique demande aux thérapeutes beaucoup de temps et d'énergie. Le contrôle du mouvement des membres inférieurs par les thérapeutes est d’autant plus difficile que l’atteinte motrice est importante. Une robotisation du déplacement des membres inférieurs permet une meilleure reproduction de la cinématique physiologique. Mais celle-ci ne peut rendre le mouvement actif au delà de la capacité motrice résiduelle du sujet. De plus, la dynamique de marche sur un tapis roulant reste différente de celle de la déambulation sur sol fixe. Il en est de même des informations proprioceptives reçues par le système nerveux central pendant un tel entraînement. De ce fait, les schémas moteurs entraînés avec cette méthode ne sont pas identiques à ceux de la marche normale à rééduquer