A critical review of neuromuscular electrical stimulation for treatment of motor dysfunction in hemiplegia

Burst-modulated wide-pulse neuromuscular electrical stimulation enhances H-reflex recruitment in rats

INTRODUCTION

In this study we investigated whether burst-modulated wide-pulse neuromuscular electrical stimulation (NMES) can improve the H-reflex and activation efficiency of sensory fibers.

METHODS

NMES-induced electromyography (EMG) was recorded from hindpaw plantar muscles in 11 anesthetized rats. A burst-modulated wide pulse (mWP) with three carrier frequencies (2 kHz, 5 kHz, and 10 kHz) and a continuous wide-pulse (WP) were delivered to the tibial nerve of each rat. The evoked Hoffman (H)-reflexes were measured to evaluate nerve activation efficiency using the H-reflex recruitment curve (HRC).

RESULTS

Relative to WP simulation, mWP stimulation required less electrical charge to excite sensory fibers and improved the H-reflex recruitment. Greater electrical charge and smaller recruitment gains were obtained with increased carrier frequency of mWP.

DISCUSSION

mWP NMES can improve stimulation efficiency and improve recruitment of sensory fibers on tibial nerve stimulation, which may help to optimize NMES stimulus parameters.

Effect of Neuromuscular Electrical Stimulation Training on the Finger Extensor Muscles for the Contralateral Corticospinal Tract in Normal Subjects: A Diffusion Tensor Tractography Study

Objectives: Neuromuscular electrical stimulation (NMES) is a popular rehabilitative modality to improve motor function of the extremities and trunk. In this study, we investigated changes of hand function and the contralateral corticospinal tract (CST) with treatment by NMES on the finger extensor muscles for 2 weeks, using serial diffusion tensor tractography (DTT).

Methods: Thirteen right handed normal subjects were recruited. Treatment was applied to the left hand (the NMES side), and the right hand was the control side. NMES was applied for 30 min/day, 7 days per week, for 2 weeks. Hand motor function was evaluated twice at pre-NMES and post-NMES training using grip strength (GS), Purdue pegboard test (PPT) and tip pinch. The fractional anisotropy (FA), mean diffusivity (MD) and tract volume (TV) of the CST in both hemispheres were measured using DTT.

Results: On the control side, the clinical scores did not differ significantly between pre- and post-NMES training (p > 0.05). However, on the NMES side, PPT and tip pinch improved significantly (p < 0.05), although GS did not. TV of the right CST increased significantly at post-NMES training (p < 0.05) whereas FA and MD did not differ significantly (p > 0.05). By contrast, FA, MD and TV on the left CST did not change significantly (p > 0.05).

Conclusion: We demonstrated facilitation of the contralateral CST with improvement of fine motor activity by 2 weeks of NMES training of peripheral muscles in normal subjects. We think our results can be applied to the normal subjects and patients with brain injury to improve the fine motor function of the hand and facilitate the normal CST or healing of the injured CST.

StartReact effects in first dorsal interosseous muscle are absent in a pinch task, but present when combined with elbow flexion

Objective

To provide a neurophysiological tool for assessing sensorimotor pathways, which may differ for those involving distal muscles in simple tasks from those involving distal muscles in a kinetic chain task, or proximal muscles in both.

Methods

We compared latencies and magnitudes of motor responses in a reaction time paradigm in a proximal (biceps brachii, BB) and a distal (first dorsal interosseous, FDI) muscle following electrical stimuli used as imperative signal (IS) delivered to the index finger. These stimuli were applied during different motor tasks: simple tasks involving either one muscle, e.g. flexing the elbow for BB (FLEX), or pinching a pen for FDI (PINCH); combined tasks engaging both muscles by pinching and flexing simultaneously (PINCH-FLEX). Stimuli were of varying intensity and occasionally elicited a startle response, and a StartReact effect.

Results

In BB, response latencies decreased gradually and response amplitudes increased progressively with increasing IS intensities for non-startling trials, while for trials containing startle responses, latencies were uniformly shortened and response amplitudes similarly augmented across all IS intensities in both FLEX and PINCH-FLEX. In FDI, response latencies decreased gradually and response amplitudes increased progressively with increasing IS intensities in both PINCH and PINCH-FLEX for non-startling trials, but, unlike in BB for the simple task, in PINCH for trials containing startle responses as well. In PINCH-FLEX, FDI latencies were uniformly shortened and amplitudes similarly increased across all stimulus intensities whenever startle signs were present.

Conclusions

Our results suggest the presence of different sensorimotor pathways supporting a dissociation between simple tasks that involve distal upper limb muscles (FDI in PINCH) from simple tasks involving proximal muscles (BB in FLEX), and combined tasks that engage both muscles (FDI and BB in PINCH-FLEX), all in accordance with differential importance in the control of movements by cortical and subcortical structures.

Significance

Simple assessment tools may provide useful information regarding the differential involvement of sensorimotor pathways in the control of both simple and combined tasks that engage proximal and distal muscles.

Percutaneous neuromuscular electrical stimulation (P-NMES) for treating shoulder pain in chronic hemiplegia. Effects on shoulder pain and quality of life

Objective: To evaluate the effect of percutaneous neuromuscular electrical stimulation (P-NMES) of the shoulder muscles on shoulder pain intensity and health-related quality of life in chronic hemiplegia.

Design: Prospective, open label design.

Setting: The outpatient services of a large teaching rehabilitation hospital in the Netherlands.

Subjects: Fifteen stroke survivors with chronic (> six months) hemiplegia and a therapy-resistant painful shoulder with subluxation. All patients suffered from clinically relevant shoulder pain, as assessed by a score of at least 4 out of 10 on a numerical rating scale. Shoulder subluxation was indicated by at least 1/2 fingerbreadth of glenohumeral separation on palpation.

Intervention: Six hours of P-NMES per day for a total of six weeks.

Main outcome measures: Shoulder pain (Brief Pain Inventory), shoulder subluxation (clinical and radiographic), shoulder pain-free external rotation (hand-held goniometer), motor impairment (Fugl-Meyer Motor test) and quality of life (SF-36) were assessed before treatment, after six weeks of intramuscular stimulation, at three months and six months follow-up.

Results: A significant reduction in pain was found on the Brief Pain Inventory. Pain reduction was still present at six months follow-up. All domains, in particular bodily pain, of the SF-36 showed improvement in the short term. After six months of follow-up, bodily pain was still strongly and significantly reduced, whereas social functioning and role physical demonstrated a nonsignificant improvement of more than 10% compared with baseline.

Conclusion: This pilot suggests that P-NMES potentially reduces shoulder pain in chronic hemiplegia. To establish the clinical value of P-NMES in treating hemiplegic shoulder pain a randomized controlled trial is needed.

Brain plasticity and rehabilitation in stroke patients

In recent years, our understanding of motor learning, neuroplasticity and functional recovery after the occurrence of brain lesion has grown significantly. Novel findings in basic neuroscience have provided an impetus for research in motor rehabilitation. The brain reveals a spectrum of intrinsic capacities to react as a highly dynamic system which can change the properties of its neural circuits. This brain plasticity can lead to an extreme degree of spontaneous recovery and rehabilitative training may modify and boost the neuronal plasticity processes. Animal studies have extended these findings, providing insight into a broad range of underlying molecular and physiological events. Neuroimaging studies in human patients have provided observations at the systems level that often parallel findings in animals. In general, the best recoveries are associated with the greatest return toward the normal state of brain functional organization. Reorganization of surviving central nervous system elements supports behavioral recovery, for example, through changes in interhemispheric lateralization, activity of association cortices linked to injured zones, and organization of cortical representational maps. Evidence from animal models suggests that both motor learning and cortical stimulation alter intracortical inhibitory circuits and can facilitate long-term potentiation and cortical remodeling. Current researches on the physiology and use of cortical stimulation animal models and in humans with stroke related hemiplegia are reviewed in this article. In particular, electromyography (EMG) -controlled electrical muscle stimulation improves the motor function of the hemiparetic arm and hand. A multi-channel near-infrared spectroscopy (NIRS) studies in which the hemoglobin levels in the brain were non-invasively and dynamically measured during functional activity found that the cerebral blood flow in the injured sensory-motor cortex area is greatest during an EMG-controlled FES session. Only a few idea is, however, known for the optimal timing of the different processes and therapeutic interventions and for their interactions in detail. Finding optimal rehabilitation paradigms requires an optimal organization of the internal processes of neural plasticity and the therapeutic interventions in accordance with defined plastic time windows. In this review the mechanisms of spontaneous plasticity after stroke and experimental interventions to enhance plasticity are summarized, with an emphasis on functional electrical stimulation therapy.

The effects of whirlpool bath and neuromuscular electrical stimulation on complex regional pain syndrome

[Purpose] The aim of the present study was to investigate and compare the effects of whirlpool bath and neuromuscular electrical stimulation on complex regional pain syndrome. [Subjects and Methods] Sixty outpatients (30 per group) with complex regional pain syndrome participated. They received 15 treatment 5 days per week for 3 weeks. The outcome measures were the visual analogue scale for pain, edema, range of motion of the wrist (flexion and extension), fingertip-to-distal palmar crease distance, hand grip strength, and pinch strength. All parameters were measured at baseline (week 0) and at the trial end (week 3). [Results] There were significant improvements in all parameters after therapy in both groups. The whirlpool bath group showed significantly better improvements in the visual analogue score, hand edema, hand grip strength, wrist range of motion (both flexion and extension), fingertip-to-distal palmar crease distance, and the three-point and fingertip pinch strengths than the neuromuscular electrical stimulation group; however, the lateral pinch strengths were similar. [Conclusion] Both whirlpool bath and neuromuscular electrical stimulation are effective in the treatment of complex regional pain syndrome, but the efficacy of the whirlpool bath treatment was better.

Comparison of Gait Aspects According to FES Stimulation Position Applied to Stroke Patients

[Purpose] This study sought to identify the gait aspects according to the FES stimulation position in stroke patients during gait training. [Subjects and Methods] To perform gait analysis, ten stroke patients were grouped based on 4 types of gait conditions: gait without FES stimulation (non-FES), gait with FES stimulation on the tibialis anterior (Ta), gait with FES stimulation on the tibialis anterior and quadriceps (TaQ), and gait with FES stimulation on the tibialis anterior and gluteus medius (TaGm). [Results] Based on repeated measures analysis of variance of measurements of gait aspects comprised of gait speed, gait cycle, and step length according to the FES stimulation position, the FES stimulation significantly affected gait aspects. [Conclusion] In conclusion, stimulating the tibialis anterior and quadriceps and stimulating the tibialis anterior and gluteus medius are much more effective than stimulating only the tibialis anterior during gait training in stroke patients using FES.

Cortical activation change induced by neuromuscular electrical stimulation during hand movements: a functional NIRS study

OBJECTIVES

Neuromuscular electrical stimulation (NMES) has been used in the field of rehabilitation for a long time. Previous studies on NMES have focused on the peripheral effect, in contrast, relatively little is known about the effect on the cerebral cortex. In the current study, we attempted to investigate the change of cortical activation pattern induced by NMES during execution of hand movements in normal subjects, using functional near infrared spectroscopy (fNIRS).

METHODS

Twelve healthy normal subjects were randomly assigned to the NMES group (six subjects) and the sham group (six subjects). We measured oxy-hemoglobin (HbO) in six regions of interest (ROI) during pre-NMES and post-NMES motor phase; the left dorsolateral and ventrolateral prefrontal cortex, premotor cortex, primary sensory-motor cortex (SM1), hand somatotopic area of SM1, and posterior parietal cortex. Between the pre-NMES and the post-NMES motor phases, real or sham NMES was applied on finger and wrist extensors of all subjects during a period of 5 minutes.

RESULTS

In all groups, during the pre-NMES motor phase, the HbO value in the hand somatotopic area of the left SM1 was higher than those of other ROIs. In the NMES group, during the post-NMES motor phase, HbO value variation in the hand somatotopic area of the left SM1 showed a significant decrease, compared with that of sham group (p < 0.05). However, in the sham group, similar aspect of results in HbO values of all ROIs was observed between pre-NMES and post-NMES motor phases (p > 0.05).

CONCLUSIONS

Results of this study showed that NMES induced a decrease of cortical activation during execution of hand movements. This finding appears to indicate that application of NMES can increase the efficiency of the cerebral cortex during execution of motor tasks.

Comparison of functional electrical stimulation associated with kinesiotherapy and kinesiotherapy alone in patients with hemiparesis during the subacute phase of ischemic cerebrovascular accident

OBJECTIVE

To compare the functional electrical stimulation associated with functional kinesiotherapy alone in patients after ischemic cerebrovascular accident.

METHODS

The study included 20 patients who were divided into two groups: Group I (GI): functional electrical stimulation plus functional kinesiotherapy and Group II (GII): functional kinesiotherapy. We evaluated active and passive range of motion, in knee flexion and extension muscle strength, activities of daily living and quality of life. The evaluations were conducted in the pretreatment period, after 10 sessions and after 20 physical therapy sessions.

RESULTS

There was a significant improvement in all variables studied for both groups. However, significant improvements for the sub-items functional capacity and social aspects were seen only in the patients treated with associated functional electrical stimulation and kinesiotherapy.

CONCLUSION

Although both groups of patients improved with the treatment, the association of functional electrical stimulation and kinesiotherapy showed superiority in two quality of life items, in the sub-items functional capacity and social aspects.

The efficacy of SMART Arm training early after stroke for stroke survivors with severe upper limb disability: a protocol for a randomised controlled trial

Background

Recovery of upper limb function after stroke is poor. The acute to subacute phase after stroke is the optimal time window to promote the recovery of upper limb function. The dose and content of training provided conventionally during this phase is however, unlikely to be adequate to drive functional recovery, especially in the presence of severe motor disability. The current study concerns an approach to address this shortcoming, through evaluation of the SMART Arm, a non-robotic device that enables intensive and repetitive practice of reaching by stroke survivors with severe upper limb disability, with the aim of improving upper limb function. The outcomes of SMART Arm training with or without outcome-triggered electrical stimulation (OT-stim) to augment movement and usual therapy will be compared to usual therapy alone.

Methods/Design

A prospective, assessor-blinded parallel, three-group randomised controlled trial is being conducted. Seventy-five participants with a first-ever unilateral stroke less than 4 months previously, who present with severe arm disability (three or fewer out of a possible six points on the Motor Assessment Scale [MAS] Item 6), will be recruited from inpatient rehabilitation facilities. Participants will be randomly allocated to one of three dose-matched groups: SMART Arm training with OT-stim and usual therapy; SMART Arm training without OT-stim and usual therapy; or usual therapy alone. All participants will receive 20 hours of upper limb training over four weeks. Blinded assessors will conduct four assessments: pre intervention (0-weeks), post intervention (4-weeks), 26 weeks and 52 weeks follow-up. The primary outcome measure is MAS item 6. All analyses will be based on an intention-to-treat principle.

Discussion

By enabling intensive and repetitive practice of a functional upper limb task during inpatient rehabilitation, SMART Arm training with or without OT-stim in combination with usual therapy, has the potential to improve recovery of upper limb function in those with severe motor disability. The immediate and long-term effects of SMART Arm training on upper limb impairment, activity and participation will be explored, in addition to the benefit of training with or without OT-stim to augment movement when compared to usual therapy alone.

Trial registration

ACTRN12608000457347

The effects of electromyography-controlled functional electrical stimulation on upper extremity function and cortical perfusion in stroke patients

OBJECTIVE

The relation was investigated between hemiparetic arm function improvement and brain cortical perfusion (BCP) change during voluntary muscle contraction (VOL), EMG-controlled FES (EMG-FES) and simple electrical muscle stimulation (ES) before and after EMG-FES therapy in chronic stroke patients.

METHODS

Sixteen chronic stroke patients with moderate residual hemiparesis underwent 5 months of task-orientated EMG-FES therapy of the paretic arm once or twice a week. Before and after treatment, arm function was clinically evaluated and BCP during VOL, ES and EMG-FES were assessed using multi-channel near-infrared spectroscopy.

RESULTS

BCP in the ipsilesional sensory-motor cortex (SMC) was greater during EMG-FES than during VOL or ES; therefore, EMG-FES caused a shift in the dominant BCP from the contralesional to ipsilesional SMC. After EMG-FES therapy, arm function improved in most patients, with some individual variability, and there was significant improvement in Fugl-Meyer (FM) score and maximal grip strength (GS). Clinical improvement was accompanied by an increase in ipsilesional SMC activation during VOL and EMG-FES condition.

CONCLUSION

The EMG-FES may have more influence on ipsilesional BCP than VOL or ES alone.

SIGNIFICANCE

The sensory motor integration during EMG-FES therapy might facilitate BCP of the ipsilesional SMC and result in functional improvement of hemiparetic upper extremity.

Breathing-controlled Electrical Stimulation (BreEStim) for management of neuropathic pain and spasticity

Electrical stimulation (EStim) refers to the application of electrical current to muscles or nerves in order to achieve functional and therapeutic goals. It has been extensively used in various clinical settings. Based upon recent discoveries related to the systemic effects of voluntary breathing and intrinsic physiological interactions among systems during voluntary breathing, a new EStim protocol, Breathing-controlled Electrical Stimulation (BreEStim), has been developed to augment the effects of electrical stimulation. In BreEStim, a single-pulse electrical stimulus is triggered and delivered to the target area when the airflow rate of an isolated voluntary inspiration reaches the threshold. BreEStim integrates intrinsic physiological interactions that are activated during voluntary breathing and has demonstrated excellent clinical efficacy. Two representative applications of BreEStim are reported with detailed protocols: management of post-stroke finger flexor spasticity and neuropathic pain in spinal cord injury.

Effect of electrical stimulation therapy on upper extremity functional recovery and cerebral cortical changes in patients with chronic hemiplegia

Hemiplegia is a common sequel of stroke and assisted living care is needed in many cases. The purpose of this study was to evaluate the effect of using surface electrode stimulation device in rehabilitation, in terms of functional improvement in upper limb and the changes in brain activation related to central nervous system reconstruction. Five patients with chronic hemiplegia received electrical stimulation therapy using the orthosis-type surface electrode stimulation device for 12 weeks. Training time was 30 min/day for the first weeks, and increased 30 min/day in every 4 weeks. Upper limb outcome measures included Brunnstrom stage, range of motion, Fugl-Meyer assessment and manual function test. Brain activation was measured using functional MRI. After therapy with therapeutic electrical stimulation (TES) for 12 weeks upper limb function improved in all cases. The results of brain activation showed two patterns. In the first, the stimulation produced an activity in the bilateral somatosensory cortices (SMC), which was seen to continue over time. The second, activation was bilateral and extensive before stimulation, but localized to the SMC after intervention. Treatment with TES using an orthosis-type electrode stimulation device improves upper limb function in chronic hemiplegia patients. The present findings suggest that there are not only efferent but also afferent effects that may promote central nervous system remodeling.

A novel neuromuscular electrical stimulation treatment for recovery of ankle dorsiflexion in chronic hemiplegia: a case series pilot study

OBJECTIVE

To evaluate the feasibility of improving active ankle dorsiflexion with contralaterally controlled neuromuscular electrical stimulation (CCNMES).

DESIGN

CCNMES dorsiflexes the paretic ankle with a stimulation intensity that is directly proportional to the degree of voluntary dorsiflexion of the unimpaired contralateral ankle, which is detected by an instrumented sock. Three subjects with chronic (>6-mo poststroke) dorsiflexor paresis participated in a 6-wk CCNMES treatment, which consisted of self-administering CCNMES-assisted ankle dorsiflexion exercises at home daily and practicing an ankle motor control task in the research laboratory twice a week.

RESULTS

For subjects 1 and 2, respectively, maximum voluntary ankle dorsiflexion increased by 13 and 17 degrees, ankle movement tracking error decreased by approximately 57% and 57%, and lower limb Fugl-Meyer score (maximum score is 34) increased by 4 and 5 points. Subject 3 had no appreciable improvement in these measures. Both subjects 1 and 2 maintained their performance in ankle movement tracking through the 3-mo follow-up; subject 2 also maintained the gains in maximum ankle dorsiflexion and Fugl-Meyer score.

CONCLUSIONS

These results suggest that CCNMES may have a positive effect on ankle motor impairment in some stroke survivors. Further investigation of the effect of CCNMES on gait is warranted.

Robotic lower limb exoskeletons using proportional myoelectric control

Robotic lower limb exoskeletons have been built for augmenting human performance, assisting with disabilities, studying human physiology, and re-training motor deficiencies. At the University of Michigan Human Neuromechanics Laboratory, we have built pneumatically-powered lower limb exoskeletons for the last two purposes. Most of our prior research has focused on ankle joint exoskeletons because of the large contribution from plantar flexors to the mechanical work performed during gait. One way we control the exoskeletons is with proportional myoelectric control, effectively increasing the strength of the wearer with a physiological mode of control. Healthy human subjects quickly adapt to walking with the robotic ankle exoskeletons, reducing their overall energy expenditure. Individuals with incomplete spinal cord injury have demonstrated rapid modification of muscle recruitment patterns with practice walking with the ankle exoskeletons. Evidence suggests that proportional myoelectric control may have distinct advantages over other types of control for robotic exoskeletons in basic science and rehabilitation.

Telerehabilitation and Electrical Stimulation: An Occupation-Based, Client-Centered Stroke Intervention

OBJECTIVE. We examined the efficacy of a remotely based arm rehabilitation regimen. A 62-year-old man participated in occupation-based, task-specific practice of activities of daily living (ADLs) &gt;3 years after stroke. The entire regimen was administered over the Internet using personal computer–based cameras and free network meeting software.

METHOD. Fugl-Meyer Assessment (FM), Action Research Arm Test (ARA), and Canadian Occupational Performance Measure (COPM) were administered before intervention. One week after treatment, FM, ARA, and COPM were readministered.

RESULTS. The participant exhibited reduced impairment and reduced functional limitation. He also expressed enhanced satisfaction with his ability to perform ADLs and rated his ADL performance better after intervention. The participant could now drive using both hands, use eating utensils, and catch and throw a ball.

CONCLUSION. Data suggest feasibility and efficacy of a remotely based, inexpensive approach using functional electrical stimulation for affected arm rehabilitation after stroke.

Gait training after stroke: a pilot study combining a gravity-balanced orthosis, functional electrical stimulation, and visual feedback

RATIONALE

This case report describes the application of a novel gait retraining approach to an individual with poststroke hemiparesis. The rehabilitation protocol combined a specially designed leg orthosis (the gravity-balanced orthosis), treadmill walking, and functional electrical stimulation to the ankle muscles with the application of motor learning principles.

CASE

The participant was a 58-year-old man who had a stroke more than three years before the intervention. He underwent gait retraining over a period of five weeks for a total of 15 sessions during which the gravity compensation provided by the gravity-balanced orthosis and visual feedback about walking performance was gradually reduced.

OUTCOMES

At the end of five weeks, he decreased the time required to complete the Timed Up and Go test; his gait speed increased during overground walking; gait was more symmetrical; stride length, hip and knee joint excursions on the affected side increased. Except for gait symmetry, all other improvements were maintained one month post-intervention.

CONCLUSIONS

This case report describes possible advantages of judiciously combining different treatment techniques in improving the gait of chronic stroke survivors. Further studies are planned to evaluate the effectiveness of different components of this training in both the subacute and chronic stages of stroke recovery.

Activity-based electrical stimulation training in a stroke patient with minimal movement in the paretic upper extremity

BACKGROUND

Existing task-specific practice interventions do not increase movement in stroke patients exhibiting minimal distal movement in the paretic upper extremity. Although often used, an important limitation of conventional electrical stimulation is that it does not involve task-specific practice.

OBJECTIVE

To determine the impact of an activity-specific electrical stimulation program on paretic limb impairment, functional limitation, and ability to perform valued activities in a subacute stroke patient exhibiting minimal paretic wrist and hand movement.

METHOD

A female subject exhibiting trace paretic hand and finger movement was administered, 9 months after stroke, the upper extremity section of the Fugl-Meyer Impairment Scale (FM), the Action Research Arm Test (ARAT), and the Arm Motor Ability Test (AMAT). She then engaged in paretic upper extremity, task-specific training incorporating an electrical stimulation neuroprosthesis. Training occurred 3 hours per day, 5 days per week for 3 weeks. The FM, ARAT, and AMAT were again administered.

RESULTS

After intervention, she exhibited reduced impairment (evidenced by an FM score change of 22 to 29), decreased functional limitation (evidenced by an ARAT score change of 4 to 10), and increased ability and speed in performing valued AMAT activities. She also reported using the paretic hand and fingers more and new abilities to perform valued activities such as playing piano.

CONCLUSION

Although conventional paretic upper extremity training strategies are ineffective in patients at this level, electrical stimulation training incorporating a neuroprosthesis appears promising.

Improving selected hand functions using a noninvasive neuroprosthesis in persons with chronic stroke

BACKGROUND AND PURPOSE

Loss of upper extremity function following stroke remains a major rehabilitation challenge. The purpose of this investigation was to determine whether the Handmaster system (NESS Ltd., Ra'anana, Israel) could improve selected hand functions in persons with chronic upper extremity paresis following stroke.

METHODS

Twenty-nine poststroke subjects consented to participate in a home-based, 3-week, nonrandomized case series trial. Main outcome measures included 3 activities of daily living (ADL) tasks: (1) lifting a 2-handled pot, (2) holding a bag while standing with a cane, and (3) a subject-selected-ADL. Secondary outcomes included lifting a 600-g weight, grip strength, electrically induced finger motion, Fugl-Meyer spherical grasp, and perceived pain scale.

RESULTS

Comparing baseline to study end point with the neuroprosthesis, the percent of successful trials with lifting the pot, weight, and bag (0% v 93%, 14% v 100%, and 17% v 93%, respectively) increased significantly. All subjects performed successfully their selected ADL and improved their Fugl-Meyer scores using the neuroprosthesis. Grip strength (6.4 +/- 7.3N v 17.7 +/- 6.2N) and active finger motion (0.5 +/- 1.2 cm v 8.4 +/- 2.6 cm) also improved with the neuroprosthesis. Pain scores significantly decreased in subjects reporting pain at baseline. Responses to questionnaire were favorable regarding the utility and therapeutic benefits of the device.

CONCLUSIONS

We conclude that the Handmaster is a safe and effective noninvasive neuroprosthesis for improving the studied hand functions and impairments in selected persons with chronic hemiplegia secondary to stroke.

Gait training combining partial body-weight support, a treadmill, and functional electrical stimulation: effects on poststroke gait

BACKGROUND AND PURPOSE

Treadmill training with harness support is a promising, task-oriented approach to restoring locomotor function in people with poststroke hemiparesis. Although the combined use of functional electrical stimulation (FES) and treadmill training with body-weight support (BWS) has been studied before, this combined intervention was compared with the Bobath approach as opposed to BWS alone. The purpose of this study was to evaluate the effects of the combined use of FES and treadmill training with BWS on walking functions and voluntary limb control in people with chronic hemiparesis.

SUBJECTS

Eight people who were ambulatory after chronic stroke were evaluated.

METHODS

An A(1)-B-A(2) single-case study design was applied. Phases A(1) and A(2) included 3 weeks of gait training on a treadmill with BWS, and phase B included 3 weeks of treadmill training plus FES applied to the peroneal nerve. The Stroke Rehabilitation Assessment of Movement was used to assess motor recovery, and a videography analysis was used to assess gait parameters.

RESULTS

An improvement (from 54.9% to 71.0%) in motor function was found during phase B. The spatial and temporal variables cycle duration, stance duration, and cadence as well as cycle length symmetry showed improvements when phase B was compared with phases A(1) and A(2).

DISCUSSION AND CONCLUSION

The combined use of FES and treadmill training with BWS led to an improvement in motor recovery and seemed to improve the gait pattern of subjects with hemiparesis, indicating the utility of this combination method during gait rehabilitation. In addition, this single-case series showed that this alternative method of gait training--treadmill training with BWS and FES--may decrease the number of people required to carry out the training.

Improvement in Functional Ambulation as a Therapeutic Effect of Peroneal Nerve Stimulation in Hemiplegia: Two Case Reports

Two chronic stroke survivors who utilized an ankle foot orthosis (AFO) prior to study entry were evaluated at baseline and after 4 weeks of daily use of a surface peroneal nerve stimulator. Participants were assessed without their dorsiflexor assistive device, using the modified Emory Functional Ambulation Profile (mEFAP). The participants demonstrated improvement in all 5 components of the mEFAP relative to baseline. These case reports indicate that enhanced functional ambulation may be an important therapeutic effect of peroneal nerve stimulation. Potential mechanisms are discussed. Controlled trials are needed to demonstrate a cause-and-effect relationship.

Neuromuscular Electrical Stimulation Improves Severe Hand Dysfunction for Individuals With Chronic Stroke

Restoring hand function is difficult post-stroke. We sought to determine if applying neuromuscular electrical stimulation (NMES) was beneficial for reducing severe hand impairments. Subjects with chronic stroke (N=8; 3 Fe, 5 M; 58.3 +/- 6.9 y/o) received 10 sessions of NMES using two different methods applied in a counterbalanced order. In one intervention, we applied NMES (active) in a novel fashion using multiple stimulators on the forearm flexors and extensors to assist subjects with grasping and releasing a tennis ball. In the other intervention, the NMES ('passive') stimulated repeated wrist extension and flexion. Motor performance was assessed prior to and immediately following the interventions and at retention. Upper extremity (UE) Fugl-Myer scores significantly improved (p < 0.002) immediately following either intervention. Significant improvement was also observed in the Modified Ashworth Spasticity Scale (MASS) (p < 0.03), immediately following intervention, primarily due to the NMESpassive treatment (p < 0.034). Subjects performed grasping tasks significantly faster (p < 0.0433) following interventions, with performance speeds on dexterous manipulation increasing approximately 10% for NMESactive immediately following intervention, compared to only 0.1% improvement following NMESpassive. Generally, improvements in motor speed remained 10 days following NMESactive intervention, although slightly diminished. In conclusion, severe hand impairment was reduced after a short duration of NMES therapy in this pilot data set for individuals with chronic stroke. NMES-assisted grasping trended towards greater functional benefit than traditional NMES-activation of wrist flexors/extensors.

A preliminary economic evaluation of percutaneous neuromuscular electrical stimulation in the treatment of hemiplegic shoulder pain

OBJECTIVE

The objective of this study was to compare the cost-effectiveness of various treatment modalities for hemiplegic shoulder pain.

DESIGN

A stage II economic evaluation.

MAIN OUTCOME MEASURES

Incremental cost effectiveness ratio of P-NMES, compared to slings and anti-inflammatory injections.

RESULTS

The incremental cost effectiveness ratio (ICER) of p-NMES, compared to anti-inflammatory injections is 6,061 euro(+/-3,285). The incremental cost of the first quality-adjusted life year after implantation of the P-NMES device compared to anti-inflammatory injections is 33,007 euro (+/-5,434). This decreases to approximately 7,000 euro after 5 years, and to approximately 5,000 euro after 10 survival years.

CONCLUSION

In this early evaluation, P-NMES seems to be cost-effective according to known guidelines. Treatment with P-NMES is recommended for patients with chronic HSP.

The Therapeutic Effect of Functional and Transcutaneous Electric Stimulation on Improving Gait Speed in Stroke Patients: A Meta-Analysis

OBJECTIVE

To determine the effect of previous treatments of functional electric stimulation (FES) and transcutaneous electric stimulation (TENS) on improving gait speed in subjects poststroke.

DATA SOURCES

Relevant articles were obtained through a search of English-language articles cited in Medline, EMBASE, CINHAL, and PubMed databases from January 1966 to May 2005.

STUDY SELECTION

Prospective clinical studies were included if electric stimulation was used to treat subjects poststroke and gait speed was used as an outcome measure. Excluded studies examined subjects with a variety of neurologic conditions, used implantable electrodes, or combined electric stimulation with treadmill training. A paired consensus between authors produced 8 articles.

DATA EXTRACTION

Two investigators extracted data independently. The methodologic quality of the studies was assessed with the Downs and Black checklist.

DATA SYNTHESIS

A fixed-effects model produced a mean difference (.18; 95% confidence interval, .08-.28) that was significant (z=3.65, P<.01), indicating the effectiveness of FES treatment at increasing gait speed in subjects poststroke. The effect sizes of the studies ranged from -.11 to 1.43 for FES and .19 to .42 for TENS. The type of FES and TENS devices, location of electrodes, amount of exposure, and subjects' stages of recovery varied between the studies.

CONCLUSIONS

FES is effective at improving gait speed in subjects poststroke. Future research should examine the effectiveness of practical and readily available FES units to improve function in subjects in the subacute stages of recovery from a stroke. These studies should attempt to use a randomized controlled design with blinding and standardized outcome measures.

Home-based electromyography-triggered stimulation in chronic stroke

OBJECTIVES

(1) To determine the feasibility of a home-based electromyography-triggered neuromuscular stimulation (ETMS) programme; and (2) to determine ETMS efficacy in increasing affected wrist extension and reducing affected arm impairment.

DESIGN

Randomized, controlled, pre-post, cross-over design.

SETTING

Outpatient rehabilitation hospital.

PATIENTS

Twelve chronic stroke patients with palpable muscle contraction in their affected wrist extensors but no movement (7 males; mean age = 59.75 years, age range 44-75 years; mean time since stroke = 52.75 months, range 13-131 months).

INTERVENTION

Subjects were randomly assigned to receive either: (a) ETMS use twice every weekday in 35-min increments during an eight-week period followed by an eight-week home exercise programme (ETMS/home exercise programme) (n=8); or (b) an eight-week home exercise programme followed by use of ETMS twice every weekday in 35-min increments during an eight-week period (home exercise programme) (n=4).

MAIN OUTCOME MEASURES

The Fugl-Meyer, Action Research Arm Test and goniometry.

RESULTS

After home exercise programme participation, subjects showed nominal or no changes on any of the outcome measures. After ETMS, patients showed modest impairment reductions, as shown by the Fugl-Meyer, and no Action Research Arm Test changes. However, both groups showed a 21 degree increase in active affected wrist extension after ETMS use.

CONCLUSION

ETMS use is feasible in the home environment. Neither participation in a traditional home exercise programme nor ETMS use conveyed changes on the Fugl-Meyer or Action Research Arm Test. However, ETMS use increased active affected limb extension. This new movement may provide a potential pathway for subjects to participate in other interventions, such as modified constraint induced therapy.

Intramuscular neuromuscular electric stimulation for poststroke shoulder pain: A multicenter randomized clinical trial 11A commercial party with a direct financial interests in the results of the research supporting this article has or will confer a benefit on the author or 1 or more of the authors. NeuroControl Corp, Valley View, OH, intends to commercialize the device evaluated in this article and has submitted a premarket 510(K)application, which is currently pending US Food and Drug Administration review. Chae and Feldstein are consultants to NeuroControl. Walker was an employee of NeuroControl, and is now a consultant to NeuroControl. Fang is an employee of NeuroControl. During this study, Yu served as a consultant to NeuroControl and Grill was an employee of NeuroControl, but neither now has an affiliation with NeuroControl

OBJECTIVE

To assess the effectiveness of intramuscular neuromuscular electric stimulation (NMES) in reducing poststroke shoulder pain.

DESIGN

Multicenter, single-blinded, randomized clinical trial.

SETTING

Ambulatory centers of 7 academic rehabilitation centers in the United States.

PARTICIPANTS

Volunteer sample of 61 chronic stroke survivors with shoulder pain and subluxation.

INTERVENTION

Treatment subjects received intramuscular NMES to the supraspinatus, posterior deltoid, middle deltoid, and trapezius for 6 hours a day for 6 weeks. Control subjects were treated with a cuff-type sling for 6 weeks. Main outcome measure Brief Pain Inventory question 12 (BPI 12), an 11-point numeric rating scale administered in a blinded manner at the end of treatment, and at 3 and 6 months posttreatment.

RESULTS

The NMES group exhibited significantly higher proportions of success based on the 3-point or more reduction in BPI 12 success criterion at the end of treatment (65.6% vs 24.1%, P<.01), at 3 months (59.4% vs 20.7%, P<.01), and at 6 months (59.4% vs 27.6%, P<.05). By using the most stringent "no pain" criterion, the NMES group also exhibited significantly higher proportions of success at the end of treatment (34.4% vs 3.4%, P<.01), at 3 months (34.4% vs 0.0%, P<.001), and at 6 months (34.4% vs 10.3%, P<.05).

CONCLUSIONS

Intramuscular NMES reduces poststroke shoulder pain among those with shoulder subluxation and the effect is maintained for at least 6 months posttreatment.

Understanding stroke recovery and rehabilitation: Current and emerging approaches

Although stroke is the third leading cause of death in the United States, it is the significant disability among survivors that has the greatest impact on healthcare and society. It is currently accepted that comprehensive rehabilitation programs improve outcome following stroke. We are now trying to discern which specific therapeutic approaches work and which do not. Years of animal research have resulted in a better understanding of what occurs in the brain following stroke and how the brain may reorganize in response to treatment. Repetitive use of the involved extremities appears key to optimal behavioral recovery and optimal brain reorganization. The advent of technology such as functional magnetic resonance imaging and transcortical magnetic stimulation has allowed the study of brain reorganization following stroke and rehabilitation in humans. Certain drugs also appear to influence neuroplasticity after stroke. Timing of therapy and drug delivery appears crucial; the optimal "critical period" has not yet been clearly identified. New approaches are slow to reach widespread adoption. Neural transplantation combined with repetitive training approaches produces behavioral recovery in animals and offers hope for the future.

Electrical stimulation driving functional improvements and cortical changes in subjects with stroke

It has been proposed that somatosensory stimulation in the form of electromyographically triggered neuromuscular electrical stimulation (NMES) to the peripheral nerve can influence functional measures of motor performance in subjects with stroke and can additionally produce changes in cortical excitability. Using a controlled, double-blind design, we studied the effects of intensive (60 h/3 weeks) treatment at home with NMES compared with a sham treatment, applied to the extensor muscles of the hemiplegic forearm to facilitate hand opening in 16 chronic stroke subjects. We investigated improvement in functional use of the hand and change in cortical activation as measured by functional magnetic resonance imaging (fMRI). Following treatment, subjects improved on measures of grasp and release of objects (Box and Block Test and Jebsen Taylor Hand Function Test [JTHFT]: small objects, stacking, heavy cans), isometric finger extension strength, and self-rated Motor Activity Log (MAL): Amount of Use and How Well score. The sham subjects did not improve on any grasp and release measure or self-rated scale, but did improve on isometric finger extension strength. Importantly, however, following crossover, these subjects improved further in the measure of strength, grasp and release (Box and Block [JTHFT]: page turning), and self-rated MAL: Amount of Use score and How Well score. Using fMRI and a finger-tracking task, an index of cortical intensity in the ipsilateral somatosensory cortex increased significantly from pre-test to post-test following treatment. Cortical activation, as measured by voxel count, did not change. These findings suggest that NMES may have an important role in stimulating cortical sensory areas allowing for improved motor function.

Efficacy of electrical stimulation in preventing or reducing subluxation of the shoulder after stroke: a meta-analysis

After stroke, up to 81% of individuals develop shoulder subluxation, a condition frequently associated with poor upper limb function. Recently, electrical stimulation has been applied to shoulder muscles to treat shoulder subluxation. The purpose of this meta-analysis was to examine the efficacy of surface electrical stimulation for the prevention or reduction of shoulder subluxation after stroke. A meta-analysis of all eligible randomised or quasi-randomised trials of electrical stimulation for the treatment of shoulder subluxation identified by computerised and hand searches of the literature was carried out. The primary outcome measure of interest was subluxation. Seven (four early and three late) trials met the inclusion criteria. The mean PEDro score out of 10 for quality of the methods was 5.8 for the four early trials and 4.3 for the three late trials. Data were pooled when subluxation was measured in millimetres. Analysis found that, when added to conventional therapy, electrical stimulation prevented on average 6.5mm of shoulder subluxation (weighted mean difference, 95% CI 4.4 to 8.6) but only reduced it by 1.9mm (weighted mean difference, 95% CI -2.3 to 6.1) compared with conventional therapy alone. Therefore, evidence supports the use of electrical stimulation early after stroke for the prevention of, but not late after stroke for the reduction of, shoulder subluxation.

Therapeutic electrical stimulation to improve motor control and functional abilities of the upper extremity after stroke: a systematic review

BACKGROUND

Therapeutic electrical stimulation (TES) is a therapeutic strategy aimed at improving impairments of the upper extremity in stroke.

OBJECTIVE

Assessment of the available evidence on the effect of TES of the affected upper extremity in improving motor control and functional abilities after stroke.

METHODS

A systematic literature search was performed to identify randomized controlled trials (RCTs) that have studied the effect of TES on motor control and functional abilities. The methodological quality of the studies was assessed systematically by two raters. The reported outcomes were examined to evaluate the effect of TES and to identify a possible relationship with patient characteristics, method of stimulation and methodological quality. When possible, effect sizes were calculated (Hedges' g).

RESULTS

Six RCTs were included. The methodological scores ranged from 7 to 16 (maximum 19). All studies assessed the effect on motor control, and four reported a positive effect. Effect sizes calculated in three studies ranged from 0.55 to 1.46. Only two studies assessed the effect on functional ability, one reported a positive effect. Subgroup analyses in two studies suggest a better response to stimulation in less severely affected patients. Apart from this, no relationship between effect and patient characteristics, method of stimulation or methodological quality could be detected.

CONCLUSIONS

The present review suggests a positive effect of electrical stimulation on motor control. No conclusions can be drawn with regard to the effect on functional abilities.