Showing papers on "Functional electrical stimulation published in 2011"

Rehabilitation of gait after stroke: a review towards a top-down approach.

Abstract: This document provides a review of the techniques and therapies used in gait rehabilitation after stroke. It also examines the possible benefits of including assistive robotic devices and brain-computer interfaces in this field, according to a top-down approach, in which rehabilitation is driven by neural plasticity. The methods reviewed comprise classical gait rehabilitation techniques (neurophysiological and motor learning approaches), functional electrical stimulation (FES), robotic devices, and brain-computer interfaces (BCI). From the analysis of these approaches, we can draw the following conclusions. Regarding classical rehabilitation techniques, there is insufficient evidence to state that a particular approach is more effective in promoting gait recovery than other. Combination of different rehabilitation strategies seems to be more effective than over-ground gait training alone. Robotic devices need further research to show their suitability for walking training and their effects on over-ground gait. The use of FES combined with different walking retraining strategies has shown to result in improvements in hemiplegic gait. Reports on non-invasive BCIs for stroke recovery are limited to the rehabilitation of upper limbs; however, some works suggest that there might be a common mechanism which influences upper and lower limb recovery simultaneously, independently of the limb chosen for the rehabilitation therapy. Functional near infrared spectroscopy (fNIRS) enables researchers to detect signals from specific regions of the cortex during performance of motor activities for the development of future BCIs. Future research would make possible to analyze the impact of rehabilitation on brain plasticity, in order to adapt treatment resources to meet the needs of each patient and to optimize the recovery process.

The Effects of Voluntary, Involuntary, and Forced Exercises on Brain-Derived Neurotrophic Factor and Motor Function Recovery: A Rat Brain Ischemia Model

Abstract: Background Stroke rehabilitation with different exercise paradigms has been investigated, but which one is more effective in facilitating motor recovery and up-regulating brain neurotrophic factor (BDNF) after brain ischemia would be interesting to clinicians and patients. Voluntary exercise, forced exercise, and involuntary muscle movement caused by functional electrical stimulation (FES) have been individually demonstrated effective as stroke rehabilitation intervention. The aim of this study was to investigate the effects of these three common interventions on brain BDNF changes and motor recovery levels using a rat ischemic stroke model.

Functional Electrical Stimulation Therapy of Voluntary Grasping Versus Only Conventional Rehabilitation for Patients With Subacute Incomplete Tetraplegia A Randomized Clinical Trial

Abstract: Background. Functional electrical stimulation therapy (FET) has a potential to improve voluntary grasping among individuals with tetraplegia secondary to traumatic spinal cord injury (SCI). Objective. This single-site, randomized controlled trial examined the efficacy of 40 hours of FET with conventional occupational therapy (COT) compared with COT alone to improve grasping. Methods. Twenty-four subjects with subacute traumatic incomplete SCI (C4-C7, AIS B-D) consented to participate in 40 hours of therapy over 8 weeks, beyond the conventional rehabilitation program. Subjects were randomized to receive FET + COT (n = 9) or COT (n = 12). The key outcomes were changes in Functional Independence Measure (FIM) self-care subscores, Spinal Cord Independence Measure (SCIM) self-care subscores, and Toronto Rehabilitation Institute Hand Function Test (TRI-HFT) performed at baseline and follow-up. Results. At the end of the treatments, the change in mean FIM self-care subscore for the FET + COT group was 20.1 versu...

Electrical stimulation for neuromuscular testing and training: state-of-the art and unresolved issues.

Abstract: Contrary to other widespread forms of electrical stimulation, such as transcutaneous electrical nerve stimulation (TENS) and functional electrical stimulation (FES), neuromuscular electrical stimulation (NMES) is generally delivered to the muscle in static conditions (without functional movement occurring) and at sufficiently high current intensities to evoke visible muscle contractions (beyond motor threshold). NMES has received increasing attention in the last few years, because it has the potential to serve as:

Functional electrical stimulation of dorsiflexor muscle: effects on dorsiflexor strength, plantarflexor spasticity, and motor recovery in stroke patients.

Abstract: Objective: To evaluate the therapeutic effects of Functional Electrical Stimulation (FES) of the tibialis anterior muscle on plantarflexor spasticity, dorsiflexor strength, voluntary ankle dorsiflexion, and lower extremity motor recovery with stroke survivors. Design: We conducted a prospective interventional study. Setting: Rehabilitation ward, physiotherapy unit and gait analysis laboratory. Participants: Fifty-one patients with foot drop resulting from stroke. Intervention: The functional electrical stimulation (FES) group (n = 27) received 20-30 minutes of electrical stimulation to the peroneal nerve and anterior tibial muscle of the paretic limb along with conventional rehabilitation program (CRP). The control group (n = 24) treated with CRP only. The subjects were treated 1 hr per day, 5 days a week, for 12 weeks. Main outcome measures :P lantarflexor spasticity measured by modified ashworth scale (MAS), dorsiflexion strength measured by manual muscle test (MMT), active/passive ankle joint dorsiflexion range of motion, and lower-extremity motor recovery by Fugl-Meyer assessment (FMA) scale. Results: After 12 weeks of treatment, there was a significant reduction in a plantarflexor spasticity by 38.3% in the FES group and 21.2% in control group ( P< 0.05), between the beginning and end of the trial. Dorsiflexor muscle strength was increased significantly by 56.6% and 27.7% in the FES group and control group, respectively. Similarly, voluntary ankle dorsiflexion and lower-extremity motor function improved significantly in both the groups. No significant differences were found in the baseline measurements among groups. When compared with control group, a significant improvement ( p< 0.05) was measured in all assessed parameters in the FES group at post-treatment assessment, thus FES therapy has better effect on recovery process in post-stroke rehabilitation. Conclusions: Therapy combining FES and conventional rehabilitation program was superior to a conventional rehabilitation program alone, in terms of reducing spasticity, improving dorsiflexor strength and lower extremity motor recovery in stroke patients.

Brain-Computer Interface Controlled Functional Electrical Stimulation System for Ankle Movement

Abstract: Many neurological conditions, such as stroke, spinal cord injury, and traumatic brain injury, can cause chronic gait function impairment due to foot-drop. Current physiotherapy techniques provide only a limited degree of motor function recovery in these individuals, and therefore novel therapies are needed. Brain-computer interface (BCI) is a relatively novel technology with a potential to restore, substitute, or augment lost motor behaviors in patients with neurological injuries. Here, we describe the first successful integration of a noninvasive electroencephalogram (EEG)-based BCI with a noninvasive functional electrical stimulation (FES) system that enables the direct brain control of foot dorsiflexion in able-bodied individuals. A noninvasive EEG-based BCI system was integrated with a noninvasive FES system for foot dorsiflexion. Subjects underwent computer-cued epochs of repetitive foot dorsiflexion and idling while their EEG signals were recorded and stored for offline analysis. The analysis generated a prediction model that allowed EEG data to be analyzed and classified in real time during online BCI operation. The real-time online performance of the integrated BCI-FES system was tested in a group of five able-bodied subjects who used repetitive foot dorsiflexion to elicit BCI-FES mediated dorsiflexion of the contralateral foot. Five able-bodied subjects performed 10 alternations of idling and repetitive foot dorsifiexion to trigger BCI-FES mediated dorsifiexion of the contralateral foot. The epochs of BCI-FES mediated foot dorsifiexion were highly correlated with the epochs of voluntary foot dorsifiexion (correlation coefficient ranged between 0.59 and 0.77) with latencies ranging from 1.4 sec to 3.1 sec. In addition, all subjects achieved a 100% BCI-FES response (no omissions), and one subject had a single false alarm. This study suggests that the integration of a noninvasive BCI with a lower-extremity FES system is feasible. With additional modifications, the proposed BCI-FES system may offer a novel and effective therapy in the neuro-rehabilitation of individuals with lower extremity paralysis due to neurological injuries.

Cycling Induced by Electrical Stimulation Improves Motor Recovery in Postacute Hemiparetic Patients: A Randomized Controlled Trial

Abstract: Background and Purpose—This study assessed whether cycling induced by functional electrical stimulation (FES) was more effective than passive cycling with placebo stimulation in promoting motor recovery and walking ability in postacute hemiparetic patients. Methods—In a double-blind, randomized, controlled trial, 35 patients were included and randomized to receive FES-induced cycling training or placebo FES cycling. The 4-week treatment consisted of 20 sessions lasting 25 minutes each. Primary outcome measures included the leg subscale of the Motricity Index and gait speed during a 50-meter walking test. Secondary outcomes were the Trunk Control Test, the Upright Motor Control Test, the mean work produced by the paretic leg, and the unbalance in mechanical work between paretic and nonparetic legs during voluntary pedaling. Participants were evaluated before training, after training, and at 3- to 5-month follow-up visits. Results—No significant differences were found between groups at baseline. Repeated-me...

Recovery of coordinated gait: randomized controlled stroke trial of functional electrical stimulation (FES) versus no FES, with weight-supported treadmill and over-ground training.

Abstract: Background. No single intervention restores the coordinated components of gait after stroke. Objective. The authors tested the multimodal Gait Training Protocol, with or without functional electric...

Predictor-Based Compensation for Electromechanical Delay During Neuromuscular Electrical Stimulation

Abstract: Electromechanical delay (EMD) is a biological artifact that arises due to a time lag between electrical excitation and tension development in a muscle. EMD is known to cause degraded performance and instability during neuromuscular electrical stimulation (NMES). Compensating for such input delay is complicated by the unknown nonlinear muscle force-length and muscle force-velocity relationships. This paper provides control development and a mathematical stability analysis of a NMES controller with a predictive term that actively accounts for EMD. The results are obtained through the development of a novel predictor-type method to address the delay in the voltage input to the muscle. Lyapunov-Krasovskii functionals are used within a Lyapunov-based stability analysis to prove semi-global uniformly ultimately bounded tracking. Experiments on able-bodied volunteers illustrate the performance and robustness of the developed controller during a leg extension trajectory following task.

Continuous neuronal ensemble control of simulated arm reaching by a human with tetraplegia

Abstract: Functional electrical stimulation (FES), the coordinated electrical activation of multiple muscles, has been used to restore arm and hand function in people with paralysis. User interfaces for such systems typically derive commands from mechanically unrelated parts of the body with retained volitional control, and are unnatural and unable to simultaneously command the various joints of the arm. Neural interface systems, based on spiking intracortical signals recorded from the arm area of motor cortex, have shown the ability to control computer cursors, robotic arms and individual muscles in intact non-human primates. Such neural interface systems may thus offer a more natural source of commands for restoring dexterous movements via FES. However, the ability to use decoded neural signals to control the complex mechanical dynamics of a reanimated human limb, rather than the kinematics of a computer mouse, has not been demonstrated. This study demonstrates the ability of an individual with long-standing tetraplegia to use cortical neuron recordings to command the real-time movements of a simulated dynamic arm. This virtual arm replicates the dynamics associated with arm mass and muscle contractile properties, as well as those of an FES feedback controller that converts user commands into the required muscle activation patterns. An individual with long-standing tetraplegia was thus able to control a virtual, two-joint, dynamic arm in real time using commands derived from an existing human intracortical interface technology. These results show the feasibility of combining such an intracortical interface with existing FES systems to provide a high-performance, natural system for restoring arm and hand function in individuals with extensive paralysis.

FES-Induced Torque Prediction With Evoked EMG Sensing for Muscle Fatigue Tracking

Abstract: This paper investigates a torque estimation method for muscle fatigue tracking, using stimulus evoked electromyography (eEMG) in the context of a functional electrical stimulation (FES) rehabilitation system. Although FES is able to effectively restore motor function in spinal cord injured (SCI) individuals, its application is inevitably restricted by muscle fatigue. In addition, the sensory feedback indicating fatigue is missing in such patients. Therefore, torque estimation is essential to provide feedback or feedforward signal for adaptive FES control. In this paper, a fatigue-inducing protocol is conducted on five SCI subjects via transcutaneous electrodes under isometric condition, and eEMG signals are collected by surface electrodes. A myoelectrical mechanical muscle model based on the Hammerstein structure with eEMG as model input is employed to capture muscle contraction dynamics. It is demonstrated that the correlation between eEMG and torque is time varying during muscle fatigue. Compared to conventional fixed-parameter models, the adapted-parameter model shows better torque prediction performance in fatiguing muscles. It motivates us to use a Kalman filter with forgetting factor for estimating the time-varying parameters and for tracking muscle fatigue. The assessment with experimental data reveals that the identified eEMG-to-torque model properly predicts fatiguing muscle behavior. Furthermore, the performance of the time-varying parameter estimation is efficient, suggesting that real-time tracking is feasible with a Kalman filter and driven by eEMG sensing in the application of FES.

Functional electrical stimulation therapies after spinal cord injury.

Abstract: The use of electricity for therapeutic purposes dates back to 15 AD, when Scribonius Largus, a court physician to the Roman emperor Claudius began using electric shocks from the torpedo ray fish to treat gout pain and headaches [1]. Although the phenomenon of electricity had been used for centuries the actual word “electricity” was not in use until the 1600’s, when William Gilbert, an English physician, coined the new Latin word “electricus” meaning like amber. The Creek word amber refers to the property of attracting small objects after being rubbed [2]. In 1780, Luigi Galvani, an Italian physician and physicist showed that impulses from nerve cells pass to muscles by demonstrating the electrical stimulation of a frog’s leg muscles [3]. Italian physicist and nephew of Luigi Galvani, Giovanni Aldini, carried on the work of his uncle by demonstrating the ability to stimulate brain tissue by applying electrical stimulation to the heads of decapitated prisoners [4]. In 1874, physician Robert Bartholow, stimulated muscle contractions while working on the cancerous brain of a live woman [5]. Research into the uses of electricity continued through the 19th and 20th centuries allowing the development of numerous inventions i.e. galvanometer, micro-electrodes, cathode ray oscilloscope, pacemakers and defibrillators [6,7]. These and other advances

Universal closed-loop electrical stimulation system

Abstract: A universal closed-loop functional electrical stimulation system comprising at least one electrode assembly adapted to deliver an electrical stimulation signal to the central nervous system, peripheral nervous system, or muscles of a user, a sensor system adapted to detect a mechanical response to a muscle stimulation signal of at least one muscle associated with a muscle group stimulated through the nervous system or proximate to the electrode assembly. An electrical stimulation device operably coupled to at least one electrode assembly and the sensor system, the electrical stimulation device including a control system to automatically receive feedback from at least one characteristic of the muscle from the detected muscle response and adjust at least one parameter of the muscle stimulation signal in real-time and in response thereto and a programmed microprocessor for controlling said electrical stimulation and receiving input from said sensor system.

Spatially Distributed Sequential Stimulation Reduces Fatigue in Paralyzed Triceps Surae Muscles: A Case Study

Abstract: Functional electrical stimulation (FES) is limited by the rapid onset of muscle fatigue caused by localized nerve excitation repeatedly activating only a subset of motor units. The purpose of this study was to investigate reducing fatigue by sequentially changing, pulse by pulse, the area of stimulation using multiple surface electrodes that cover the same area as one electrode during conventional stimulation. Paralyzed triceps surae muscles of an individual with complete spinal cord injury were stimulated, via the tibial nerve, through four active electrodes using spatially distributed sequential stimulation (SDSS) that was delivered by sending a stimulation pulse to each electrode one after another with 90° phase shift between successive electrodes. For comparison, single electrode stimulation was delivered through one active electrode. For both modes of stimulation, the resultant frequency to the muscle as a whole was 40 Hz. Isometric ankle torque was measured during fatiguing stimulations lasting 2 min. Each mode of stimulation was delivered a total of six times over 12 separate days. Three fatigue measures were used for comparison: fatigue index (final torque normalized to maximum torque), fatigue time (time for torque to drop by 3 dB), and torque-time integral (over the entire trial). The measures were all higher during SDSS (P < 0.001), by 234, 280, and 171%, respectively. The results are an encouraging first step toward addressing muscle fatigue, which is one of the greatest problems for FES.

Review: Clinical benefits of functional electrical stimulation cycling exercise for subjects with central neurological impairments

Abstract: Functional electrical stimulation (FES) cycling ergometer has been utilized in recent decades for rehabilitation by sequentially stimulating the large leg-actuating muscles of paralyzed leg muscles to produce cyclical leg motion. A number of studies reported physiological adaptations after regular FES-cycling exercise (FESCE) training in subjects with spinal cord injury, stroke, cerebral palsy and other conditions. This article provides a comprehensive overview of general aspects of FES cycling systems and clinical applications of FESCE. The studies cited in this article provide supportive findings for the potential clinical efficacy of FESCE for reducing the risk of secondary medical complications in subjects with paralysis. The potential therapeutic benefits of FESCE include conditioning the cardiopulmonary, muscular, and skeletal systems, and improving other physiological and psychological performances. Our recent pilot study also indicated that the decrease of leg spasticity in subjects with cerebral palsy is one of the acute effects of FESCE. In conclusion, we recommend that FESCE is of benefit in a variety of aspects to improve the general condition and to prevent deterioration in subjects with central neurological impairments.

Functional electrical stimulation therapy for grasping in traumatic incomplete spinal cord injury: randomized control trial.

Abstract: The purpose of this single-site randomized control trial was to assess the short-term and long-term efficacy of functional electrical stimulation (FES) therapy over conventional occupational therapy in improving voluntary hand function in incomplete C4-C7 spinal cord injury individuals. All 22 participants recruited in this randomized control trial received treatment for both the left and right upper extremities. Every participant, irrespective of group allocation, received one dose (60 min per day, 5 days per week for the duration of 8 weeks) of conventional occupational therapy for hand function. Of the 22 participants, 12 individuals received an additional dose of conventional occupational therapy, while the remaining 10 participants received a dose of FES hand therapy. The primary outcome measure was Functional Independence Measure (FIM) self-care subscore. The secondary outcome measures were Spinal Cord Independence Measure (SCIM) self-care subscore and Toronto Rehabilitation Institute Hand Function Test (TRI-HFT). The participants who received FES therapy showed significantly greater improvements in hand function at discharge, and were able to maintain their gains at long-term follow-up as assessed using FIM self-care subscore, SCIM self-care subscore, and TRI-HFT. The FES therapy effectively increased independence and thereby improved quality of life of individuals with tetraplegia when compared with conventional occupational therapy.

Muscle, tendons, and bone: structural changes during denervation and FES treatment.

Abstract: Objectives: This paper describes a novel approach to determine structural changes in bone, muscle, and tendons using medical imaging, finite element models, and processing techniques to evaluate and quantify: (1) progression of atrophy in permanently lower motor neuron (LMN) denervated human muscles, and tendons; (2) their recovery as induced by functional electrical stimulation (FES); and (3) changes in bone mineral density and bone strength as effect of FES treatment. Methods: Briefly, we used three-dimensional reconstruction of muscle belly, tendons, and bone images to study the structural changes occurring in these tissues in paralysed subjects after complete lumbar-ischiadic spinal cord injury (SCI). These subjects were recruited through the European project RISE, an endeavour designed to establish a novel clinical rehabilitation method for patients who have permanent and non-recoverable muscle LMN denervation in the lower extremities. This paper describes the use of segmentation tec...

Treatment of Rat Spinal Cord Injury with the Neurotrophic Factor Albumin-Oleic Acid: Translational Application for Paralysis, Spasticity and Pain

Abstract: Sensorimotor dysfunction following incomplete spinal cord injury (iSCI) is often characterized by the debilitating symptoms of paralysis, spasticity and pain, which require treatment with novel pleiotropic pharmacological agents. Previous in vitro studies suggest that Albumin (Alb) and Oleic Acid (OA) may play a role together as an endogenous neurotrophic factor. Although Alb can promote basic recovery of motor function after iSCI, the therapeutic effect of OA or Alb-OA on a known translational measure of SCI associated with symptoms of spasticity and change in nociception has not been studied. Following T9 spinal contusion injury in Wistar rats, intrathecal treatment with: i) Saline, ii) Alb (0.4 nanomoles), iii) OA (80 nanomoles), iv) Alb-Elaidic acid (0.4/80 nanomoles), or v) Alb-OA (0.4/80 nanomoles) were evaluated on basic motor function, temporal summation of noxious reflex activity, and with a new test of descending modulation of spinal activity below the SCI up to one month after injury. Albumin, OA and Alb-OA treatment inhibited nociceptive Tibialis Anterior (TA) reflex activity. Moreover Alb-OA synergistically promoted early recovery of locomotor activity to 50±10% of control and promoted de novo phasic descending inhibition of TA noxious reflex activity to 47±5% following non-invasive electrical conditioning stimulation applied above the iSCI. Spinal L4–L5 immunohistochemistry demonstrated a unique increase in serotonin fibre innervation up to 4.2±1.1 and 2.3±0.3 fold within the dorsal and ventral horn respectively with Alb-OA treatment when compared to uninjured tissue, in addition to a reduction in NR1 NMDA receptor phosphorylation and microglia reactivity. Early recovery of voluntary motor function accompanied with tonic and de novo phasic descending inhibition of nociceptive TA flexor reflex activity following Alb-OA treatment, mediated via known endogenous spinal mechanisms of action, suggests a clinical application of this novel neurotrophic factor for the treatment of paralysis, spasticity and pain.

Phase-lead iterative learning control algorithms for functional electrical stimulation-based stroke rehabilitation

Abstract: A control system for stroke rehabilitation is developed which combines electrical stimulation with a robotic support system to provide assistance to stroke patients performing 3D upper limb reaching tasks in a virtual reality environment. The electrical stimulation is applied to two muscles in the subject's arm using an iterative learning control scheme which learns from data collected over previous trials of the task in order to achieve accurate movement. The principal components of the system are described and experimental results confirm its feasibility for application to upper limb stroke rehabilitation.

Electrochemical activation and inhibition of neuromuscular systems through modulation of ion concentrations with ion-selective membranes

Abstract: Conventional functional electrical stimulation aims to restore functional motor activity of patients with disabilities resulting from spinal cord injury or neurological disorders. However, intervention with functional electrical stimulation in neurological diseases lacks an effective implantable method that suppresses unwanted nerve signals. We have developed an electrochemical method to activate and inhibit a nerve by electrically modulating ion concentrations in situ along the nerve. Using ion-selective membranes to achieve different excitability states of the nerve, we observe either a reduction of the electrical threshold for stimulation by up to approximately 40%, or voluntary, reversible inhibition of nerve signal propagation. This low-threshold electrochemical stimulation method is applicable in current implantable neuroprosthetic devices, whereas the on-demand nerve-blocking mechanism could offer effective clinical intervention in disease states caused by uncontrolled nerve activation, such as epilepsy and chronic pain syndromes.

Decreased central fatigue in multiple sclerosis patients after 8 weeks of surface functional electrical stimulation.

Abstract: Effective treatments for multiple sclerosis (MS)-associated central fatigue have not been established. Surface functional electrical stimulation (FES), which can challenge the peripheral neuromuscular system without overloading the central nervous system, is a relatively safe therapeutic strategy. We investigated the effect of 8 weeks of surface FES training on the levels of general, central, and peripheral fatigue in MS patients. Seven of nine individuals with MS (average age: 42.86 +/- 13.47 years) completed 8 weeks of quadriceps muscle surface FES training. Maximal voluntary contraction, voluntary activation level, twitch force, General Fatigue Index (FI), Central Fatigue Index (CFI), Peripheral Fatigue Index, and Modified Fatigue Impact Scale (MFIS) scores were determined before and after training. The results showed that FI (p = 0.01), CFI (p = 0.02), and MFIS (p = 0.02) scores improved significantly after training. Improvements in central fatigue contributed significantly to improvements in general fatigue (p < 0.01). The results of the current study showed that central fatigue was a primary limitation in patients with MS during voluntary exercise and that 8 weeks of surface FES training for individuals with MS led to significantly reduced fatigue, particularly central fatigue.

The effect of electrical passive cycling on spasticity in war veterans with spinal cord injury.

Abstract: Introduction: Muscle atrophy, spasticity and deformity are among long term complication of Spinal Cord Injury(SCI) veterans. There are numerous studies evaluating effect of functional electrical stimulation (FES) on muscle properties of SCI people, but less research has focused on the benefits of passive cycling in the management of spasm and improving ROM of lower limbs in individuals with SCI. Aims: To evaluate the effect of electrical passive cycling on passive range of movement spasticity and electrodiagnostic parameters in SCI veterans. Methods: 64 SCI veterans referred to two clinical and research center in Tehran were recruited in this prospective clinical trial. The subjects were divided into 2 groups according to electrical passive cycling usage: 1) patients who didn’t use pedal exercise(control group), 2) patients used Electrical passive cycling up to optimal level (intervention group) . Main outcome measures included hip, knee and ankle rang of motion, spacticity scale, and electrodiagnostic parameters including F-Wave Consistency, F-Wave Amplitude, H/M Ratio, F/M Ratio, H Reflex Onset Latency and H Reflex Amplitude. Data were recorded at the time of receiving and one year after pedal exercise usage. Results : Sixty four SCI patients including 95.3% male, 4.7% female with mean age 43 years old were included in this study. All patients except one had complete SCI suffered from complete SCI. The involved spinal levels were cervical(17.2%), upper thoracic (34.4%), lower thoracic (45.3%) and lumbar (3.1%). Spasticity scale decreased significantly after passive cycling in group 2 and 3. Also hip, knee and ankle ROM in group 2 and 3 were significantly improved after pedal exercise. There was a significant difference in H max/M max (RT<) and F/M ratio after versus before electric passive cycling system in group 2. Conclusion: These findings suggest that passive rythmic leg exercise can lead to decrease in spasticity ,increase in passive ROM of low

Electrochemical activation and inhibition of neuromuscular systems through modulation of ion concentrations with ion-selective membranes

Abstract: Conventional functional electrical stimulation aims to restore functional motor activity of patients with disabilities resulting from spinal cord injury or neurological disorders. However, intervention with functional electrical stimulation in neurological diseases lacks an effective implantable method that suppresses unwanted nerve signals. We have developed an electrochemical method to activate and inhibit a nerve by electrically modulating ion concentrations in situ along the nerve. Using ion-selective membranes to achieve different excitability states of the nerve, we observe either a reduction of the electrical threshold for stimulation by up to approximately 40%, or voluntary, reversible inhibition of nerve signal propagation. This low-threshold electrochemical stimulation method is applicable in current implantable neuroprosthetic devices, whereas the on-demand nerve-blocking mechanism could offer effective clinical intervention in disease states caused by uncontrolled nerve activation, such as epilepsy and chronic pain syndromes.

OrthoJacket: an active FES-hybrid orthosis for the paralysed upper extremity.

Abstract: The loss of the grasp function in cervical spinal cord injured (SCI) patients leads to life-long dependency on caregivers and to a tremendous decrease of the quality of life. This article introduces the novel non-invasive modular hybrid neuro-orthosis OrthoJacket for the restoration of the restricted or completely lost hand and arm functions in high tetraplegic SCI individuals. The primary goal of the wearable orthosis is to improve the paralysed upper extremity function and, thus, to enhance a patient's independence in activities of daily living. The system combines the advantage of orthotics in mechanically stabilising joints together with the possibilities of functional electrical stimulation for activation of paralysed muscles. In patients with limited capacity, for force generation, flexible fluidic actuators are used to support the movement. Thus, the system is not only intended for functional restoration but also for training. Several sensor systems together with an intelligent signal processing allow for automatic adaptation to the anatomical and neurological individualities of SCI patients. The integration of novel user interfaces based on residual muscle activities and detection of movement intentions by real-time data mining methods will enable the user to autonomously control the system in a natural and cooperative way.