A novel functional electrical stimulation treatment for recovery of hand function in hemiplegia: 12-week pilot study

Contralaterally controlled functional electrical stimulation video game therapy for hand rehabilitation after stroke: a randomized controlled trial

PURPOSE

To estimate the effect of integrating custom-designed hand therapy video games (HTVG) with contralaterally controlled functional electrical stimulation (CCFES) therapy.

METHODS

Fifty-two stroke survivors with chronic (>6 months) upper limb hemiplegia were randomized to 12 weeks of CCFES or CCFES + HTVG. Treatment involved self-administration of technology-mediated therapy at home plus therapist-administered CCFES-assisted task practice in the lab. Pre- and post-treatment assessments were made of hand dexterity, upper limb impairment and activity limitation, and cognitive function.

RESULTS

No significant between-group differences were found on any outcome measure, and the average magnitudes of improvement within both groups were small. The incidence of technical problems with study devices at home was greater for the CCFES + HTVG group. This negatively affected adherence and may partially explain the absence of effect of HTVG. At end-of-treatment, large majorities of both treatment groups had positive perceptions of treatment efficacy and expressed enthusiasm for the treatments.

CONCLUSION

This study makes an important contribution to the research literature on the importance of environmental factors, concomitant impairments, and technology simplification when designing technology-based therapies intended to be self-administered at home. This study failed to show any added benefit of HTVG to CCFES therapy.Clinicaltrials.gov (NCT03058796).

Hand-worn devices for assessment and rehabilitation of motor function and their potential use in BCI protocols: a review

Introduction

Various neurological conditions can impair hand function. Affected individuals cannot fully participate in activities of daily living due to the lack of fine motor control. Neurorehabilitation emphasizes repetitive movement and subjective clinical assessments that require clinical experience to administer.

Methods

Here, we perform a review of literature focused on the use of hand-worn devices for rehabilitation and assessment of hand function. We paid particular attention to protocols that involve brain-computer interfaces (BCIs) since BCIs are gaining ground as a means for detecting volitional signals as the basis for interactive motor training protocols to augment recovery. All devices reviewed either monitor, assist, stimulate, or support hand and finger movement.

Results

A majority of studies reviewed here test or validate devices through clinical trials, especially for stroke. Even though sensor gloves are the most commonly employed type of device in this domain, they have certain limitations. Many such gloves use bend or inertial sensors to monitor the movement of individual digits, but few monitor both movement and applied pressure. The use of such devices in BCI protocols is also uncommon.

Discussion

We conclude that hand-worn devices that monitor both flexion and grip will benefit both clinical diagnostic assessment of function during treatment and closed-loop BCI protocols aimed at rehabilitation.

LiDAR-Based Hand Contralateral Controlled Functional Electrical Stimulation System

Contralateral controlled functional electrical stimulation (CCFES) can induce simultaneous movements in patients' bilateral hands. It has been clinically proven to be effective in improving hand motor control and dexterity. sEMG and bending sensor-based data gloves for detecting patients' motor intent have been developed with limitations. sEMG sensor signals are unstable and susceptible to noise. Data gloves composed of bending sensors require complicated calibration and tend to have data drift. In this paper, a LiDAR-based system for hand CCFES is proposed. The method utilized LiDAR to detect the patient's motion intention without contact in CCFES systems. It has been clinically proven that LiDARs can effectively distinguish the different motion amplitudes of hand gestures as quantitative evaluation sensors of functional electrical stimulation (FES). Training data for classifiers were collected from 9 healthy individuals and 15 stroke patients performing 4 gestures, including hand opening, fist clenching, wrist extension, and wrist flexion. The support vector machine (SVM), linear discriminant analysis (LDA), and k-nearest neighbor (kNN) were verified for their classification performance in offline hand gesture recognition tests. Experiments were also conducted on 6 stroke volunteers to evaluate gestures triggered by FES. The SVM classifier showed excellent classification performance for four hand gestures, with an average F1-score of 0.97 ± 0.05 in offline tests. As for online gesture recognition, an average F1-score of 0.92 ± 0.09 was obtained. In the evaluation experiments, between data from 50% and 100% movement amplitude, paired t-tests showed significant differences. The experimental results indicated that the proposed system showed promise for hand rehabilitation.

Abnormal synergies and associated reactions post-hemiparetic stroke reflect muscle activation patterns of brainstem motor pathways

Individuals with moderate-to-severe post-stroke hemiparesis cannot control proximal and distal joints of the arm independently because they are constrained to stereotypical movement patterns called flexion and extension synergies. Accumulating evidence indicates that these synergies emerge because of upregulation of diffusely projecting brainstem motor pathways following stroke-induced damage to corticofugal pathways. During our recent work on differences in synergy expression among proximal and distal joints, we serendipitously observed some notable characteristics of synergy-driven muscle activation. It seemed that: paretic wrist/finger muscles were activated maximally during contractions of muscles at a different joint; differences in the magnitude of synergy expression occurred when elicited via contraction of proximal vs. distal muscles; and associated reactions in the paretic limb occurred during maximal efforts with the non-paretic limb, the strength of which seemed to vary depending on which muscles in the non-paretic limb were contracting. Here we formally investigated these observations and interpreted them within the context of the neural mechanisms thought to underlie stereotypical movement patterns. If upregulation of brainstem motor pathways occurs following stroke-induced corticofugal tract damage, then we would expect a pattern of muscle dependency in the observed behaviors consistent with such neural reorganization. Twelve participants with moderate-to-severe hemiparetic stroke and six without stroke performed maximal isometric torque generation in eight directions: shoulder abduction/adduction and elbow, wrist, and finger flexion/extension. Isometric joint torques and surface EMG were recorded from shoulder, elbow, wrist, and finger joints and muscles. For some participants, joint torque and muscle activation generated during maximal voluntary contractions were lower than during maximal synergy-induced contractions (i.e., contractions about a different joint), particularly for wrist and fingers. Synergy-driven contractions were strongest when elicited via proximal joints and weakest when elicited via distal joints. Associated reactions in the wrist/finger flexors were stronger than those of other paretic muscles and were the only ones whose response depended on whether the non-paretic contraction was at a proximal or distal joint. Results provide indirect evidence linking the influence of brainstem motor pathways to abnormal motor behaviors post-stroke, and they demonstrate the need to examine whole-limb behavior when studying or seeking to rehabilitate the paretic upper limb.

Encoder-Controlled Functional Electrical Stimulator for Bilateral Wrist Activities—Design and Evaluation

Upper limb impairment following stroke is often characterized by limited voluntary control in the affected arm. In addition, significant motor coordination problems occur on the unaffected arm due to avoidance of performing bilateral symmetrical activities. Rehabilitation strategies should, therefore, not only aim at improving voluntary control on the affected arm, but also contribute to synchronizing activity from both upper limbs. The encoder-controlled functional electrical stimulator, described in this paper, implements precise contralateral control of wrist flexion and extension with electrical stimulation. The stimulator is calibrated for each individual to obtain a table of stimulation parameters versus wrist angle. This table is used to set stimulation parameters dynamically, based on the difference in wrist angle between the set and stimulated side, which is continuously monitored. This allows the wrist on the stimulated side to follow flexion and extension patterns on the set side, thereby mirroring wrist movements of the normal side. This device also gives real-time graphical feedback on how the stimulated wrist is performing in comparison to the normal side. A study was performed on 25 normal volunteers to determine how closely wrist movements on the set side were being followed on the stimulated side. Graphical results show that there were minor differences, which were quantified by considering the peak angles of flexion and extension on the set and stimulated side for each participant. The mean difference in peak flexion and extension range of movement was 2.3 degrees and 1.9 degrees, respectively, with a mean time lag of 1 s between the set and the stimulated angle graphs.

Contralaterally controlled neuromuscular electrical stimulation-induced changes in functional connectivity in patients with stroke assessed using functional near-infrared spectroscopy

Contralaterally controlled neuromuscular electrical stimulation (CCNMES) is an innovative therapy in stroke rehabilitation which has been verified in clinical studies. However, the underlying mechanism of CCNMES are yet to be comprehensively revealed. The main purpose of this study was to apply functional near-infrared spectroscopy (fNIRS) to compare CCNMES-related changes in functional connectivity (FC) within a cortical network after stroke with those induced by neuromuscular electrical stimulation (NMES) when performing wrist extension with hemiplegic upper extremity. Thirty-one stroke patients with right hemisphere lesion were randomly assigned to CCNMES (n = 16) or NMES (n = 15) groups. Patients in both groups received two tasks: 10-min rest and 10-min electrical stimulation task. In each task, the cerebral oxygenation signals in the prefrontal cortex (PFC), bilateral primary motor cortex (M1), and primary sensory cortex (S1) were measured by a 35-channel fNIRS. Compared with NMES, FC between ipsilesional M1 and contralesional M1/S1 were significantly strengthened during CCNMES. Additionally, significantly higher coupling strengths between ipsilesional PFC and contralesional M1/S1 were observed in the CCNMES group. Our findings suggest that CCNMES promotes the regulatory functions of ipsilesional prefrontal and motor areas as well as contralesional sensorimotor areas within the functional network in patients with stroke.

Upper Extremity Contralaterally Controlled Functional Electrical Stimulation Versus Neuromuscular Electrical Stimulation in Post-Stroke Individuals: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Electrical stimulation has been employed as a safe and effective therapy for improving arm function after stroke. Contralaterally controlled functional electrical stimulation (CCFES) is a unique method that has progressed from application in small feasibility studies to implementation in several randomized controlled trials. However, no meta-analysis has been conducted to summarize its efficacy.

OBJECTIVE

To summarize the effect size of CCFES through measures of upper extremity motor recovery compared with that of neuromuscular electrical stimulation (NMES).

METHODS

The PubMed, Cochrane Library, EMBASE, Scopus, and Google Scholar databases were searched. Randomized controlled trials (RCTs) were selected and subjected to meta-analysis and risk of bias assessment.

RESULTS

6 RCTs were selected and 267 participants were included. The Upper Extremity Fugl-Meyer assessment (UEFMA) was included in all studies, the Box and Blocks test (BBT) and active range of motion (AROM) were included in 3 and 4 studies, respectively. The modified Barthel Index (mBI) and Arm Motor Abilities Test (AMAT) were included in 2 and 3 studies, respectively. The CCFES group demonstrated greater improvement than the NMES did in UEFMA (SMD = .42, 95% CI = .07-.76), BBT (SMD = .48, 95% CI = .10-.86), AROM (SMD = .54, 95% CI = .23-.86), and mBI (SMD = .54, 95% CI = .12-.97). However, the results for AMAT did not differ significantly (SMD = .34, 95% CI = -.03-.72).

CONCLUSION

Contralaterally controlled functional electrical stimulation produced greater improvements in upper extremity hemiplegia in people with stroke than NMES did. PROSPERO registration number: CRD42021245831.

Efficacy of contralaterally controlled functional electrical stimulation compared to cyclic neuromuscular electrical stimulation and task-oriented training for recovery of hand function after stroke: study protocol for a multi-site randomized controlled trial

BACKGROUND

Multi-site studies in stroke rehabilitation are important for determining whether a technology and/or treatment can be successfully administered by sites other than the originating site and with similar positive outcomes. This study is the first multi-site clinical trial of a novel intervention for post-stroke upper limb rehabilitation called contralaterally controlled functional electrical stimulation (CCFES). Previous pilot and single-site studies showed positive effects of CCFES on upper limb impairment and hand dexterity in stroke survivors. The main purpose of this study is to confirm and demonstrate the efficacy of CCFES in a larger group of most likely responders across multiple clinical sites.

METHODS

Up to 129 stroke survivors with moderate to severe upper extremity hemiparesis at 4 clinical trial sites will be randomized to CCFES, cyclic neuromuscular electrical stimulation (cNMES), or task-oriented-training (TOT). Participants will receive 12 weeks of group-specific therapy. Blinded assessments of upper limb impairment and activity limitation, quality of life, and neurophysiology will be used to compare outcomes at baseline, after treatment, and up to 6 months post-treatment. The primary endpoint is change in dexterity from baseline to 6 months post-treatment.

DISCUSSION

Loss of hand function following stroke is a major rehabilitation problem affecting millions of people per year globally. More effective rehabilitation therapies are needed to restore hand function in these individuals. This study will determine whether CCFES therapy produces greater improvements in upper extremity function than cNMES or TOT, and will begin to elucidate the different mechanisms underlying each of the three treatments. This multi-site study is a critical step in advancing a novel method of rehabilitation toward clinical translation and widespread dissemination.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03574623 . Registered prior to first enrollment; July 2, 2018.

Effectiveness of a Novel Contralaterally Controlled Neuromuscular Electrical Stimulation for Restoring Lower Limb Motor Performance and Activities of Daily Living in Stroke Survivors: A Randomized Controlled Trial

Background

Contralaterally controlled neuromuscular electrical stimulation (CCNMES) is a novel electrical stimulation treatment for stroke; however, reports on the efficacy of CCNMES on lower extremity function after stroke are scarce.

Objective

To compare the effects of CCNMES versus NMES on lower extremity function and activities of daily living (ADL) in subacute stroke patients.

Methods

Forty-four patients with a history of subacute stroke were randomly assigned to a CCNMES group and a NMES group (n = 22 per group). Twenty-one patients in each group completed the study per protocol, with one subject lost in follow-up in each group. The CCNMES group received CCNMES to the tibialis anterior (TA) and the peroneus longus and brevis muscles to induce ankle dorsiflexion motion, whereas the NMES group received NMES. The stimulus current was a biphasic waveform with a pulse duration of 200 μs and a frequency of 60 Hz. Patients in both groups underwent five 15 min sessions of electrical stimulation per week for three weeks. Indicators of motor function and ADL were measured pre- and posttreatment, including the Fugl–Meyer assessment of the lower extremity (FMA-LE) and modified Barthel index (MBI). Surface electromyography (sEMG) assessments included average electromyography (aEMG), integrated electromyography (iEMG), and root mean square (RMS) of the paretic TA muscle.

Results

Values for the FMA-LE, MBI, aEMG, iEMG, and RMS of the affected TA muscle were significantly increased in both groups after treatment (p < 0.01). Patients in the CCNMES group showed significant improvements in all the measurements compared with the NMES group after treatment. Within-group differences in all post- and pretreatment indicators were significantly greater in the CCNMES group than in the NMES group (p < 0.05).

Conclusion

CCNMES improved motor function and ADL ability to a greater extent than the conventional NMES in subacute stroke patients.

Motor Cortical Plasticity Induced by Volitional Muscle Activity-Triggered Transcranial Magnetic Stimulation and Median Nerve Stimulation

Bilateral motor training is a useful method for modifying corticospinal excitability. The effects of bilateral movement that are caused by artificial stimulation on corticospinal excitability have not been reported. We compared motor-evoked potentials (MEPs) of the primary motor cortex (M1) after conventional bilateral motor training and artificial bilateral movements generated by electromyogram activity of abductor pollicis brevis (APB) muscle-triggered peripheral nerve stimulation (c-MNS) and transcranial magnetic stimulation of the ipsilateral M1 (i-TMS). A total of three protocols with different interventions—bilateral finger training, APB-triggered c-MNS, and APB-triggered i-TMS—were administered to 12 healthy participants. Each protocol consisted of 360 trials of 30 min for each trial. MEPs that were induced by single-pulse TMS, short-interval intracortical inhibition (SICI), and intracortical facilitation (ICF) that were induced by paired-pulse TMS were assessed as outcome measures at baseline and at 0, 20, 40, and 60 min after intervention. MEP amplitude significantly increased up to 40 min post-intervention in all protocols compared to that at the baseline, although there were some differences in the changing pattern of ICF and SICI in each protocol. These findings suggest that artificial bilateral movement has the potential to increase the ipsilateral cortical excitability of the moving finger.

Home-Based Functional Electrical Stimulation-Assisted Hand Therapy Video Games for Children With Hemiplegia: Development and Proof-of-Concept

We describe the development and three case reports of a home-based intervention for children with hand hemiplegia that integrates custom video games with contralaterally controlled functional electrical stimulation (CCFES). With CCFES, stimulated opening of the more-affected hand is modulated by volitional opening of the less-affected hand. Video games that solicit goal-oriented, skill-requiring movement have shown promise for treating hemiplegia, but they have not previously been combined with electrical stimulation in children. Three children ages 8, 9, and 11 with moderate-to-severe hand hemiplegia were assigned six weeks of therapy in lab and at home. The goal was to determine if children could tolerate 9 lab treatment sessions and administer up to 7.5 hrs/wk of CCFES video game therapy at home. The feasibility of this intervention for home use was assessed by device logs, end-of-treatment interviews, and motor function/impairment assessments. With caregiver help, the children were all able to attend 9 lab sessions and built up to 7.5 hrs/wk of therapy by week 3. They averaged 5-7 hrs/wk of home intervention overall. Motor outcomes improved for all three participants at treatment end, but mostly regressed at 4-weeks follow-up. Individual improvements at treatment end exceeded minimum detectable or clinically important thresholds for Assisting Hands Assessment, Fugl-Meyer Assessment, and Melbourne Motor Assessment 2. We found preliminary indications that CCFES-integrated video game therapy can provide a high dose of hand motor control therapy at home and in the lab. Improvements in motor outcomes were also observed, but more development and study is needed.

Bilateral Contralaterally Controlled Functional Electrical Stimulation Reveals New Insights Into the Interhemispheric Competition Model in Chronic Stroke

Background. Upper-limb chronic stroke hemiplegia was once thought to persist because of disproportionate amounts of inhibition imposed from the contralesional on the ipsilesional hemisphere. Thus, one rehabilitation strategy involves discouraging engagement of the contralesional hemisphere by only engaging the impaired upper limb with intensive unilateral activities. However, this premise has recently been debated and has been shown to be task specific and/or apply only to a subset of the stroke population. Bilateral rehabilitation, conversely, engages both hemispheres and has been shown to benefit motor recovery. To determine what neurophysiological strategies bilateral therapies may engage, we compared the effects of a bilateral and unilateral based therapy using transcranial magnetic stimulation. Methods. We adopted a peripheral electrical stimulation paradigm where participants received 1 session of bilateral contralaterally controlled functional electrical stimulation (CCFES) and 1 session of unilateral cyclic neuromuscular electrical stimulation (cNMES) in a repeated-measures design. In all, 15 chronic stroke participants with a wide range of motor impairments (upper extremity Fugl-Meyer score: 15 [severe] to 63 [mild]) underwent single 1-hour sessions of CCFES and cNMES. We measured whether CCFES and cNMES produced different effects on interhemispheric inhibition (IHI) to the ipsilesional hemisphere, ipsilesional corticospinal output, and ipsilateral corticospinal output originating from the contralesional hemisphere. Results. CCFES reduced IHI and maintained ipsilesional output when compared with cNMES. We found no effect on ipsilateral output for either condition. Finally, the less-impaired participants demonstrated a greater increase in ipsilesional output following CCFES. Conclusions. Our results suggest that bilateral therapies are capable of alleviating inhibition on the ipsilesional hemisphere and enhancing output to the paretic limb.

Ability of people with post-stroke hemiplegia to self-administer FES-assisted hand therapy video games at home: An exploratory case series

Introduction

This article describes the development and initial clinical testing of an innovative home-based treatment for upper extremity hemiplegia that integrates contralaterally controlled functional electrical stimulation with hand therapy video games.

Methods

We explored the ability of seven participants with moderate-to-severe hand impairment to self-administer 12 weeks of contralaterally controlled functional electrical stimulation video game therapy at home for 10 h/week and in-lab with a therapist for four h/week. Clinical suitability was assessed by device usage logs, qualitative surveys, and clinical motor and cognitive outcomes.

Results

Three participants completed the study with > 95% compliance and four did not. Factors linked to incompletion included development of trigger finger in the non-paretic hand, acceptance of a new full-time job, residence relocation, and persistence of drowsiness from anti-spasticity medication. Those who completed the treatment perceived qualitative benefits and experienced gains in motor and cognitive outcomes.

Conclusion

Individuals with moderate-to-severe chronic post-stroke upper extremity hemiplegia can self-administer contralaterally controlled functional electrical stimulation video game therapy for up to 90 min/day at home. We also identified social and physiological factors that may preclude its use for daily home treatment. Further studies are warranted and are in progress to estimate treatment effect and optimal dose of this intervention.

A pilot study into reaching performance after severe to moderate stroke using upper arm support

Stroke effects millions of people each year and can have a significant impact on the ability to use the impaired arm and hand. One of the results of stroke is the development of an abnormal shoulder-elbow flexion synergy, where lifting the arm can cause the elbow, wrist, and finger flexors to involuntarily contract, reducing the ability to reach with the arm and hand opening. This study explored the effect of using support at the upper arm to improve hand and arm reaching performance. Nine participants were studied while performing a virtual reaching task under three conditions: while the weight of their impaired arm was supported by a robot arm, while unsupported, and while using their non-impaired arm. Most subjects exhibited faster and more accurate reaching while supported compared to unsupported. For the subjects who could voluntarily open their hand, most were able to more swiftly open their hand when using upper arm support. In many cases, performance with support was not statistically different than the unaffected arm and hand. Muscle activity of the impaired limb with upper arm support showed decreased effort to lift the arm and reduced biceps activity in most subjects, pointing to a reduction in the abnormal flexion synergy while using upper arm support. While arm support can help to reduce the activation of abnormal synergies, weakness resulting from hemiparesis remains an issue impacting performance. Future systems will need to address both of these causes of disability to more fully restore function after stroke.

FES-UPP: A Flexible Functional Electrical Stimulation System to Support Upper Limb Functional Activity Practice

There is good evidence supporting highly intensive, repetitive, activity-focused, voluntary-initiated practice as a key to driving recovery of upper limb function following stroke. Functional electrical stimulation (FES) offers a potential mechanism to efficiently deliver this type of therapy, but current commercial devices are too inflexible and/or insufficiently automated, in some cases requiring engineering support. In this paper, we report a new, flexible upper limb FES system, FES-UPP, which addresses the issues above. The FES-UPP system consists of a 5-channel stimulator running a flexible FES finite state machine (FSM) controller, the associated setup software that guides therapists through the setup of FSM controllers via five setup stages, and finally the Session Manager used to guide the patient in repeated attempts at the activities(s) and provide feedback on their performance. The FSM controller represents a functional activity as a sequence of movement phases. The output for each phase implements the stimulations to one or more muscles. Progression between movement phases is governed by user-defined rules. As part of a clinical investigation of the system, nine therapists used the FES-UPP system to set up FES-supported activities with twenty two patient participants with impaired upper-limbs. Therapists with little or no FES experience and without any programming skills could use the system in their usual clinical settings, without engineering support. Different functional activities, tailored to suit the upper limb impairment levels of each participant were used, in up to 8 sessions of FES-supported therapy per participant. The efficiency of delivery of the therapy using FES-UPP was promising when compared with published data on traditional face-face therapy. The FES-UPP system described in this paper has been shown to allow therapists with little or no FES experience and without any programming skills to set up state-machine FES controllers bespoke to the patient's impairment patterns and activity requirements, without engineering support. The clinical results demonstrated that the system can be used to efficiently deliver high intensity, activity-focused therapy. Nevertheless, further work to reduce setup time is still required.

Real-time and wearable functional electrical stimulation system for volitional hand motor function control using the electromyography bridge method

Voluntary participation of hemiplegic patients is crucial for functional electrical stimulation therapy. A wearable functional electrical stimulation system has been proposed for real-time volitional hand motor function control using the electromyography bridge method. Through a series of novel design concepts, including the integration of a detecting circuit and an analog-to-digital converter, a miniaturized functional electrical stimulation circuit technique, a low-power super-regeneration chip for wireless receiving, and two wearable armbands, a prototype system has been established with reduced size, power, and overall cost. Based on wrist joint torque reproduction and classification experiments performed on six healthy subjects, the optimized surface electromyography thresholds and trained logistic regression classifier parameters were statistically chosen to establish wrist and hand motion control with high accuracy. Test results showed that wrist flexion/extension, hand grasp, and finger extension could be reproduced with high accuracy and low latency. This system can build a bridge of information transmission between healthy limbs and paralyzed limbs, effectively improve voluntary participation of hemiplegic patients, and elevate efficiency of rehabilitation training.

Contralaterally Controlled Functional Electrical Stimulation Improves Hand Dexterity in Chronic Hemiparesis: A Randomized Trial

BACKGROUND AND PURPOSE

It is unknown whether one method of neuromuscular electrical stimulation for poststroke upper limb rehabilitation is more effective than another. Our aim was to compare the effects of contralaterally controlled functional electrical stimulation (CCFES) with cyclic neuromuscular electrical stimulation (cNMES).

METHODS

Stroke patients with chronic (>6 months) moderate to severe upper extremity hemiparesis (n=80) were randomized to receive 10 sessions/wk of CCFES- or cNMES-assisted hand opening exercise at home plus 20 sessions of functional task practice in the laboratory for 12 weeks. The task practice for the CCFES group was stimulation assisted. The primary outcome was change in Box and Block Test (BBT) score at 6 months post treatment. Upper extremity Fugl-Meyer and Arm Motor Abilities Test were also measured.

RESULTS

At 6 months post treatment, the CCFES group had greater improvement on the BBT, 4.6 (95% confidence interval [CI], 2.2-7.0), than the cNMES group, 1.8 (95% CI, 0.6-3.0), between-group difference of 2.8 (95% CI, 0.1-5.5), P=0.045. No significant between-group difference was found for the upper extremity Fugl-Meyer (P=0.888) or Arm Motor Abilities Test (P=0.096). Participants who had the largest improvements on BBT were <2 years post stroke with moderate (ie, not severe) hand impairment at baseline. Among these, the 6-month post-treatment BBT gains of the CCFES group, 9.6 (95% CI, 5.6-13.6), were greater than those of the cNMES group, 4.1 (95% CI, 1.7-6.5), between-group difference of 5.5 (95% CI, 0.8-10.2), P=0.023.

CONCLUSIONS

CCFES improved hand dexterity more than cNMES in chronic stroke survivors.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00891319.

Development of network-based multichannel neuromuscular electrical stimulation system for stroke rehabilitation

Neuromuscular electrical stimulation (NMES) is a promising assistive technology for stroke rehabilitation. Here we present the design and development of a multimuscle stimulation system as an emerging therapy for people with paretic stroke. A network-based multichannel NMES system was integrated based on dual bus architecture of communication and an H-bridge current regulator with a power booster. The structure of the system was a body area network embedded with multiple stimulators and a communication protocol of controlled area network to transmit muscle stimulation parameter information to individual stimulators. A graphical user interface was designed to allow clinicians to specify temporal patterns and muscle stimulation parameters. We completed and tested a prototype of the hardware and communication software modules of the multichannel NMES system. The prototype system was first verified in nondisabled subjects for safety, and then tested in subjects with stroke for feasibility with assisting multijoint movements. Results showed that synergistic stimulation of multiple muscles in subjects with stroke improved performance of multijoint movements with more natural velocity profiles at elbow and shoulder and reduced acromion excursion due to compensatory trunk rotation. The network-based NMES system may provide an innovative solution that allows more physiological activation of multiple muscles in multijoint task training for patients with stroke.

Who May Benefit From Armeo Power Treatment? A Neurophysiological Approach to Predict Neurorehabilitation Outcomes

BACKGROUND

The Armeo Power, a rehabilitation exoskeleton that allows early treatment of motor disabilities, provides intelligent arm support in a large 3-dimensional work space, thus enabling patients to perform intensive, repetitive, and goal-oriented exercises. This device could efficiently induce new connections and facilitate plasticity phenomena potentiation. Knowledge of the potential brain plasticity reservoir after brain damage constitutes a prerequisite for an optimal rehabilitation strategy.

OBJECTIVE

To identify potential neurophysiologic markers predicting the responsiveness of stroke patients to upper limb robotic treatment.

DESIGN

Prospective cohort study.

SETTING

Behavioral and Robotic Neurorehabilitation Laboratory of IRCCS Centro Neurolesi Bonino-Pulejo, Messina, Italy.

PATIENTS

We enrolled 35 patients who had sustained a first-ever ischemic supratentorial stroke at least 2 months before enrollment and had unilateral hemiplegia.

METHODS

All patients underwent 40 Armeo Power training sessions that lasted 1 hour each (ie, 5 times a week for 8 weeks).

MAIN OUTCOME MEASUREMENTS

We assessed the spasticity and motor function of the upper limb by means of the Modified Ashworth scale and Fugl-Meyer assessment, respectively. Moreover, we evaluated the cortical excitability and plasticity potential of the bilateral primary motor areas in response to the repetitive paired associative stimulation paradigm using transcranial magnetic stimulation and Armeo Power kinematic parameters.

RESULTS

The patients who showed significant repetitive paired associative stimulation aftereffects at baseline exhibited an evident increase of cortical plasticity in the affected hemisphere (motor evoked potential amplitude increase, P = .03), a decrease of interhemispheric inhibition (affected hemisphere cortical silent period duration decrease, P = .01; unaffected hemisphere cortical silent period duration increase, P = .004; repetitive paired associative stimulation aftereffect increase, P = .008). Such findings were paralleled by clinical improvements (Fugl-Meyer, P = .04) and Armeo Power kinematic improvements (elbow flexion/extension, P = .02; shoulder range of movement, P = .002).

CONCLUSIONS

Our data suggest that use of Armeo Power may improve upper limb motor function recovery as predicted by reshaping of cortical and transcallosal plasticity, according to the baseline cortical excitability.

LEVEL OF EVIDENCE

IV.

Improving arm function in chronic stroke: a pilot study of sensory amplitude electrical stimulation via glove electrode during task-specific training

OBJECTIVE

To investigate the effects of sensory amplitude electrical stimulation (SES) delivered by glove electrode during task-specific exercise on arm movement, function, and sensation in chronic stroke.

METHODS

The design was an intervention pilot study, pre-test, post-test, follow-up design. The settings used were a university research laboratory and home-based intervention. Participants comprised of 11 individuals with chronic stroke (7.2 ± 4.1 years post onset) and moderate arm paresis, 10.82/20 ± 2.27 on the Stroke Rehabilitation Assessment of Movement (STREAM) - Arm Subscale. Participants were seven males and four females (mean age: 59 years). Participants were recruited from university-based database. Intervention- Participants engaged in task-specific training at home for 30 min, twice daily, for 5 weeks, while receiving SES via glove electrode. Participants received supervised task practice at least twice during intervention period for 1 hour. Main outcome measures- Jebsen-Taylor Hand Function Test (JTHFT), STREAM - Arm Subscale, Motor Activity Log-14 (MAL-14) - Amount and Quality Subscales, and Nottingham Stereognosis Assessment (NSA).

RESULTS

Significant changes were found in group mean pre- and post-test comparisons on the NSA (P = 0.042), MAL amount subscale (P = 0.047), and JTHFT (with writing item 29 excluded) (P = 0.003) and in pre-test to follow-up comparisons on NSA (P = 0.027) and JTHFT (writing item excluded) (P = 0.009). There was no significant change on the STREAM (P = 1.0). Individuals with a greater baseline motor capacity determined by STREAM scores (P = 0.048) and more recent stroke (P = 0.014) had significantly greater improvements.

CONCLUSION

Combining task-specific training with glove-based SES in chronic stroke resulted in changes in arm sensation and function that were maintained at 3-month follow-up.

Prediction of muscle activity during loaded movements of the upper limb

Background

Accurate prediction of electromyographic (EMG) signals associated with a variety of motor behaviors could, in theory, serve as activity templates needed to evoke movements in paralyzed individuals using functional electrical stimulation. Such predictions should encompass complex multi-joint movements and include interactions with objects in the environment.

Methods

Here we tested the ability of different artificial neural networks (ANNs) to predict EMG activities of 12 arm muscles while human subjects made free movements of the arm or grasped and moved objects of different weights and dimensions. Inputs to the trained ANNs included hand position, hand orientation, and thumb grip force.

Results

The ability of ANNs to predict EMG was equally as good for tasks involving interactions with external loads as for unloaded movements. The ANN that yielded the best predictions was a feed-forward network consisting of a single hidden layer of 30 neural elements. For this network, the average coefficient of determination (R² value) between predicted and actual EMG signals across all nine subjects and 12 muscles during movements that involved episodes of moving objects was 0.43.

Conclusion

This reasonable accuracy suggests that ANNs could be used to provide an initial estimate of the complex patterns of muscle stimulation needed to produce a wide array of movements, including those involving object interaction, in paralyzed individuals.

Contributions to muscle force and EMG by combined neural excitation and electrical stimulation

OBJECTIVE

Stimulation of muscle for research or clinical interventions is often superimposed on ongoing physiological activity without a quantitative understanding of the impact of the stimulation on the net muscle activity and the physiological response. Experimental studies show that total force during stimulation is less than the sum of the isolated voluntary and stimulated forces, but the occlusion mechanism is not understood.

APPROACH

We develop a model of efferent motor activity elicited by superimposing stimulation during a physiologically activated contraction. The model combines action potential interactions due to collision block, source resetting, and refractory periods with previously published models of physiological motor unit recruitment, rate modulation, force production, and EMG generation in human first dorsal interosseous muscle to investigate the mechanisms and effectiveness of stimulation on the net muscle force and EMG.

MAIN RESULTS

Stimulation during a physiological contraction demonstrates partial occlusion of force and the neural component of the EMG, due to action potential interactions in motor units activated by both sources. Depending on neural and stimulation firing rates as well as on force-frequency properties, individual motor unit forces can be greater, smaller, or unchanged by the stimulation. In contrast, voluntary motor unit EMG potentials in simultaneously stimulated motor units show progressive occlusion with increasing stimulus rate. The simulations predict that occlusion would be decreased by a reverse stimulation recruitment order.

SIGNIFICANCE

The results are consistent with and provide a mechanistic interpretation of previously published experimental evidence of force occlusion. The models also predict two effects that have not been reported previously--voluntary EMG occlusion and the advantages of a proximal stimulation site. This study provides a basis for the rational design of both future experiments and clinical neuroprosthetic interventions involving either motor or sensory stimulation.

The influence of functional electrical stimulation on hand motor recovery in stroke patients: a review

Neuromuscular stimulation has been used as one potential rehabilitative treatment option to restore motor function and improve recovery in patients with paresis. Especially stroke patients who often regain only limited hand function would greatly benefit from a therapy that enhances recovery and restores movement. Multiple studies investigated the effect of functional electrical stimulation on hand paresis, the results however are inconsistent. Here we review the current literature on functional electrical stimulation on hand motor recovery in stroke patients. We discuss the impact of different parameters such as stage after stoke, degree of impairment, spasticity and treatment protocols on the functional outcome. Importantly, we outline the results from recent studies investigating the cortical effects elicited by functional electrical stimulation giving insights into the underlying mechanisms responsible for long-term treatment effects. Bringing together the findings from present research it becomes clear that both, treatment outcomes as well as the neurophysiologic mechanisms causing functional recovery, vary depending on patient characteristics. In order to develop unified treatment guidelines it is essential to conduct homogenous studies assessing the impact of different parameters on rehabilitative success.

Contralaterally controlled functional electrical stimulation for recovery of elbow extension and hand opening after stroke: a pilot case series study

OBJECTIVE

The aims of this study were to determine whether patients with moderate-to-severe upper limb hemiplegia could use contralaterally controlled functional electrical stimulation at the arm and hand (Arm+Hand CCFES) at home and to evaluate the feasibility of Arm+Hand CCFES to reduce arm and hand motor impairment.

DESIGN

With Arm+Hand CCFES, the paretic elbow and hand extensors were stimulated with intensities proportional to the degree of elbow extension and hand opening, respectively, of the contralateral unimpaired side. For 12 wks, four participants with chronic (≥6 mos) upper limb hemiplegia received ∼7 hrs per week of self-administered home-based stimulation-mediated elbow extension and hand opening exercise plus ∼2.5 hrs per week of therapist-supervised laboratory-based stimulation-assisted functional task practice. Assessments of upper limb impairment were made at pretreatment, posttreatment, and 1 mo after treatment.

RESULTS

All four participants were able to use the Arm+Hand CCFES system at home either independently or with very minimal assistance from a caregiver. All four participants had increases in the Fugl-Meyer score (1-9 points) and the Wolf Motor Function Test (0.2-0.8 points) and varying degrees of improvement in maximum hand opening, maximum elbow extension, and simultaneous elbow extension and hand opening.

CONCLUSIONS

Arm+Hand CCFES can be successfully administered in stroke patients with moderate-to-severe impairment and can reduce various aspects of upper limb impairment. A larger efficacy study is warranted.

Contralaterally controlled neuromuscular electrical stimulation for recovery of ankle dorsiflexion: a pilot randomized controlled trial in patients with chronic post-stroke hemiplegia

OBJECTIVE

The aim of this study was to compare the effects of contralaterally controlled neuromuscular electrical stimulation (CCNMES) vs. cyclic neuromuscular electrical stimulation (NMES) on lower extremity impairment, functional ambulation, and gait characteristics.

DESIGN

Twenty-six survivors of stroke with chronic (≥6 mos) foot drop during ambulation were randomly assigned to 6 wks of CCNMES or cyclic NMES. Both groups had ten sessions per week of self-administered home application of either CCNMES or cyclic NMES plus two sessions per week of gait training with a physical therapist. Primary outcomes included lower extremity Fugl-Meyer score, modified Emory Functional Ambulation Profile, and gait velocity. Assessments were made at pretreatment and posttreatment and at 1 and 3 mos after treatment.

RESULTS

There were no significant differences between the groups in the outcome trajectories for any of the measures. With data from both groups pooled, there were significant but modest and sustained improvements in the Fugl-Meyer score and the modified Emory Functional Ambulation Profile but not in gait velocity.

CONCLUSIONS

The results support the hypothesis that gait training combined with either CCNMES or cyclic NMES reduces lower extremity impairment and functional ambulation but do not support the hypothesis that CCNMES is more effective than cyclic NMES in patients with chronic post-stroke hemiplegia.

Contralaterally controlled functional electrical stimulation for stroke rehabilitation

Contralaterally controlled functional electrical stimulation (CCFES) is an innovative method of delivering neuromuscular electrical stimulation for rehabilitation of paretic limbs after stroke. It is being studied to evaluate its efficacy in improving recovery of arm and hand function and ankle dorsiflexion in chronic and subacute stroke patients. The initial studies provide preliminary evidence supporting the efficacy of CCFES.

Effectiveness of finger-equipped electrode (FEE)-triggered electrical stimulation improving chronic stroke patients with severe hemiplegia

Background:

Electric stimulation (ES) has been recognized as an effective method to improve motor function to paralysed patients with stroke. It is important for ES to synchronize with voluntary movement. To enhance this co-ordination, the finger-equipped electrode (FEE) was developed. The purpose of this study was to evaluate FEE in improving motor function of upper extremities (UEs) in patients with chronic stroke.

Methods and subjects:

The study participants included four patients with chronic stroke who received FEE electronic stimulation (FEE-ES) plus passive and active training and three control patients who underwent training without FEE-ES. The patients were treated five times weekly for 4 weeks. UE motor function was evaluated before and after treatment using Fugl-Meyer Assessment (FMA) and Brunnstrom recovery staging.

Results:

The mean age of patients in each group was 60-years and there was a mean of 49 months since the onset of symptoms. All patients had severe UE weakness. The patients receiving FEE-ES had greater improvement in UE function than control patients (total, proximal and distal FMA, p < 0.05; Brunnstrom staging of UE, p < 0.05).

Discussion:

The results indicate that FEE-ES may be an effective treatment for patients with chronic stroke.

Restoring voluntary grasping function in individuals with incomplete chronic spinal cord injury: pilot study

BACKGROUND

Functional electrical stimulation (FES) therapy has been shown to be one of the most promising approaches for improving voluntary grasping function in individuals with subacute cervical spinal cord injury (SCI).

OBJECTIVE

To determine the effectiveness of FES therapy, as compared to conventional occupational therapy (COT), in improving voluntary hand function in individuals with chronic (≥24 months post injury), incomplete (American Spinal Injury Association Impairment Scale [AIS] B-D), C4 to C7 SCI.

METHODS

Eight participants were randomized to the intervention group (FES therapy; n = 5) or the control group (COT; n = 3). Both groups received 39 hours of therapy over 13 to 16 weeks. The primary outcome measure was the Toronto Rehabilitation Institute-Hand Function Test (TRI-HFT), and the secondary outcome measures were Graded Redefined Assessment of Strength Sensibility and Prehension (GRASSP), Functional Independence Measure (FIM) self-care subscore, and Spinal Cord Independence Measure (SCIM) self-care subscore. Outcome assessments were performed at baseline, after 39 sessions of therapy, and at 6 months following the baseline assessment.

RESULTS

After 39 sessions of therapy, the intervention group improved by 5.8 points on the TRI-HFT's Object Manipulation Task, whereas the control group changed by only 1.17 points. Similarly, after 39 sessions of therapy, the intervention group improved by 4.6 points on the FIM self-care subscore, whereas the control group did not change at all.

CONCLUSION

The results of the pilot data justify a clinical trial to compare FES therapy and COT alone to improve voluntary hand function in individuals with chronic incomplete tetraplegia.

Clinical effects of combined bilateral arm training with functional electrical stimulation in patients with stroke

Cerebral vascular disease (or stroke) is the main cause of disabilities in adults. Upper-limb dysfunction after stroke usually exists, leading to severe limits of motor capabilities as well as daily activities. Therefore, effective treatment interventions for upper-limb rehabilitation after stroke are needed. Based on the neurophysiological evidence and clinical measures, combined bilateral arm training (BAT) with functional electric stimulation (FES) could improve hand function in stroke patients. In this study, we attempt to combine BAT with FES applying to the post-stroke paretic arm. A linear guide platform with FES feedback control was developed to execute the training of bilateral reaching movements. 35 stroke subjects were recruited and divided into two groups (BAT with FES and BAT alone). 23 participants completed this experiment with 3-week intervention. According to our preliminary results, a favorable trend toward improvement in experimental group (BAT with FES) existed after treatment and at follow-up. Further analysis would be conducted to investigate the kinematic change on motor performance. Moreover, various treatment doses as well as more functional approaches would also be considered for better effects of upper limb rehabilitation after stroke.

Neuromuscular electrical stimulation for skeletal muscle function

Lack of neural innervation due to neurological damage renders muscle unable to produce force. Use of electrical stimulation is a medium in which investigators have tried to find a way to restore movement and the ability to perform activities of daily living. Different methods of applying electrical current to modify neuromuscular activity are electrical stimulation (ES), neuromuscular electrical stimulation (NMES), transcutaneous electrical nerve stimulation (TENS), and functional electrical stimulation (FES). This review covers the aspects of electrical stimulation used for rehabilitation and functional purposes. Discussed are the various parameters of electrical stimulation, including frequency, pulse width/duration, duty cycle, intensity/amplitude, ramp time, pulse pattern, program duration, program frequency, and muscle group activated, and how they affect fatigue in the stimulated muscle.

Efficacy of Armeo® Spring during the chronic phase of stroke. Study in mild to moderate cases of hemiparesis

OBJECTIVE

To evaluate the efficacy of a gravity-supported, computer-enhanced device (Armeo® Spring) for upper limb rehabilitation in chronic stroke patients.

MATERIAL AND METHODS

We included 23 chronic hemiparetic patients (chronicity: 328 ± 90.8 days; distribution: 17 men and 6 women) aged 54.6 ± 9.5 years, who had sustained ischaemic stroke (n=12) or haemorrhagic stroke (n=11). All patients completed 36 one-hour sessions using the Armeo® Spring system. Arm movement was assessed at the beginning and end of the treatment programme and once more 4 months later. Main outcome measurements covered structure, activity, and function, as per the International Classification of Functioning, Disability and Health: Modified Ashworth Scale, Motricity Index (MI), Fugl-Meyer Assessment Scale (FM), Motor Assessment Scale (MAS), Manual Function Test (MFT), and Wolf Motor Function Test (WMFT).

RESULTS

Repeated measures ANOVA showed significant improvement (time effect) for all function scales (P<.01 for FM and MI) and activity scales (P<.01 for MAS, MFT and WMFT-ability, and P<.05 WMFT-time) without significant changes in muscle tone. The post-hoc analysis (Bonferroni) showed different evolutionary patterns for function and activity measurements, and clear benefits related to Armeo® Spring training, especially on activity scales.

CONCLUSIONS

Armeo® Spring is an effective tool for rehabilitating the affected arm in patients with hemiparesis secondary to ictus, even in the chronic stage.

A pilot study of contralateral homonymous muscle activity simulated electrical stimulation in chronic hemiplegia

OBJECTIVE

For the recovery of hemiparetic hand function, a therapy was developed called contralateral homonymous muscle activity stimulated electrical stimulation (CHASE), which combines electrical stimulation and bilateral movements, and its feasibility was studied in three chronic stroke patients with severe hand hemiparesis.

METHODS

Patients with a subcortical lesion were asked to extend their wrist and fingers bilaterally while an electromyogram (EMG) was recorded from the extensor carpi radialis (ECR) muscle in the unaffected hand. Electric stimulation was applied to the homonymous wrist and finger extensors of the affected side. The intensity of the electrical stimulation was computed based on the EMG and scaled so that the movements of the paretic hand looked similar to those of the unaffected side. The patients received 30-minutes of therapy per day for 2 weeks.

RESULTS

Improvement in the active range of motion of wrist extension was observed for all patients. There was a decrease in the scores of modified Ashworth scale in the flexors. Fugl-Meyer assessment scores of motor function of the upper extremities improved in two of the patients.

CONCLUSIONS

The results suggest a positive outcome can be obtained using the CHASE system for upper extremity rehabilitation of patients with severe hemiplegia.

Afferent stimulation provided by glove electrode during task-specific arm exercise following stroke

Background:

Sensory amplitude electrical stimulation (SES) and repetitive task practice reduce impairments and arm dysfunction when delivered separately following stroke.

Objective:

To determine if home-based, task-specific arm exercise was more effective when administered concurrent with SES.

Methods:

Thirty-eight subjects with chronic stroke and mean Fugl-Meyer Assessment (FMA) score 28/66 (15–45) participated. Subjects were randomly assigned to an SES ( n = 20) or sham stimulation ( n = 18) group. Subjects engaged in task-based home exercise for 30 minutes, twice daily, for four weeks while wearing a glove electrode on the impaired hand. Experimental subjects received SES while control subjects received sham stimulation during exercise. Primary outcome measures: FMA and Arm Motor Ability Test (AMAT).

Results:

There were no significant between-group differences for outcome measures. There was a significant difference between the pre- and post-test scores in the SES group AMAT median time ( P = 0.003 95% confidence interval (CI): −14.304, −6.365; effect size: 0.84). Practice time was not associated with changes in outcomes. Subjects with more sensorimotor dysfunction had significantly greater improvements on AMAT median time ( P = 0.037). There was a significant relationship between baseline FMA score and FMA change score ( r = 0.402; P = 0.006).

Conclusions:

This study describes a unique SES delivery system via glove electrode that enabled delivery of SES during home-based arm task practice in stroke survivors. Task practice with concurrent SES did not demonstrate significantly better effects than task practice with sham stimulation, however there was a trend for greater improvement in one activity measure.

Development of a network FES system for stroke rehabilitation

This paper describes a Functional Electrical Stimulation (FES) system based on the distributed network structure for rehabilitation of stroke patients. This FES system performs surface stimulation to activate the nerve of paretic muscles for training stroke patients to relearn motor functions. The main components of the networked FES system include a master unit (MU), a distributed stimulation-sensor unit (DSSU), and a clinical computer. In this system, the MU can drive a set of DSSUs, which is located at the node on the distributed network structure. The MU also stores the stimulation plan of rehabilitation training prescribed by clinicians. The DSSU serves as a single channel stimulator whose current amplitude, duration and frequency can be modulated by the MU. This system has two distinctive characters. First, since a stimulator is designed as a node on the network, the number of stimulation channels could be expanded according to specific needs. Second, a sensor component can be incorporated in the DSSU to allow monitoring physiological variables. The two features of system design make the networked FES system practical and flexible in clinical applications. We have completed a prototype of system including hardware and software. The evaluation test indicates that the system performance meets design specifications.

Contralaterally controlled functional electrical stimulation for upper extremity hemiplegia: an early-phase randomized clinical trial in subacute stroke patients

BACKGROUND

Contralaterally controlled functional electrical stimulation (CCFES) is an experimental treatment intended to improve hand function after stroke.

OBJECTIVE

To compare the effects of 6 weeks of CCFES versus cyclic neuromuscular electrical stimulation (NMES) on upper extremity impairment and activity limitation in patients ≤6 months poststroke.

METHODS

Twenty-one participants were randomized to CCFES or cyclic NMES. Treatment for both groups consisted of daily stimulation-assisted repetitive hand-opening exercise at home plus twice-weekly lab sessions of functional task practice. Assessments were made at pretreatment and posttreatment and at 1 month and 3 months posttreatment. They included maximum voluntary finger extension angle, finger movement tracking error, upper extremity Fugl-Meyer score, Box and Blocks test, and Arm Motor Abilities test. Treatment effects were estimated using a 2-factor repeated measures analysis of variance with the value of the baseline measure as a covariate.

RESULTS

Seventeen patients completed the treatment phase (9 CCFES, 8 cyclic NMES). At all posttreatment time points, CCFES produced larger improvements than cyclic NMES on every outcome measure. Maximum voluntary finger extension showed the largest treatment effect, with a mean group difference across the posttreatment time points of 28° more finger extension for CCFES.

CONCLUSIONS

The results favor CCFES over cyclic NMES though the small sample size limits the statistical power of the study. The effect size estimates from this study will be used to power a larger trial.

Effectiveness of Hybrid Assistive Neuromuscular Dynamic Stimulation Therapy in Patients With Subacute Stroke

Background and objective. Hybrid assistive neuromuscular dynamic stimulation (HANDS) therapy was devised to facilitate the use of the hemiparetic upper extremity in daily life by combining assistive neuromuscular electrical stimulation, referred to as the integrated volitional electrical stimulator (IVES), with a splint. The aim of this study is to assess the effectiveness of HANDS therapy for patients with subacute stroke. Methods. The participants were 24 inpatients receiving rehabilitation for hemiparetic stroke within 60 days of onset. Entry criteria included inability to individuate finger extension. Patients were randomly assigned to 2 groups. The HANDS group (n = 12) used the IVES combined with a wrist splint for 8 hours a day for 3 weeks, and the control group (n = 12) wore a wrist splint alone. All patients received the same daily dose and length of standard poststroke multidisciplinary rehabilitation. Outcome measures were the upper extremity portion of the Fugl-Meyer Assessment (FMA), Action Research Arm Test (ARAT), and Motor Activity Log-14 (MAL). Results. In all, 10 patients in each group completed the interventions. Compared with the control group, the HANDS group showed significantly greater gains in distal (wrist/hand) portion of the FMA ( P < .01) and improvement of the ARAT ( P < .05). The gains in the MAL did not differ. No adverse effects occurred and the HANDS therapy was well accepted. Conclusion. HANDS therapy in addition to conventional therapy may improve hand function in patients with moderate to severe hand impairment during early rehabilitation.

Accelerometer-triggered electrical stimulation for reach and grasp in chronic stroke patients: a pilot study

BACKGROUND

Electrical stimulation of the upper extremity may reduce impairment in patients following stroke. Stimulation triggered on demand combined with task practice may be an effective means of promoting recovery of function.

OBJECTIVE

The authors investigated the feasibility of using accelerometer-controlled electrical stimulation for the elbow, wrist, and finger extensors to enable functional task practice in patients with chronic hemiparesis.

METHODS

Following a 4-week baseline, participants received 2 weeks of cyclic stimulation exercise to elbow and forearm extensor muscles, followed by 10 weeks of triggered stimulation to practice functional reaching. Participants were reassessed 12 weeks later as well. Outcome measures were the Action Research Arm Test (ARAT), Modified Ashworth Scale (MAS), Canadian Occupational Performance Measure (COPM), Psychosocial Impact of Assistive Devices Scale (PIADS), and Use of Device Questionnaire (UDQ).

RESULTS

Fifteen volunteers who had at least 45° of forward shoulder flexion and could initiate elbow extension and grasp completed the study. The ARAT score improved from 19 to 32 (P = .002); the MAS score for elbow, wrist, and finger flexor spasticity was reduced from 2 each to 1, 0, and 1 (P < .05); the COPM performance and satisfaction scores improved (P = .001); and the PIADS became positive for competence (P = .005), adaptability (P = .008), and self-esteem (P = .008). Gains were maintained 12 weeks later.

CONCLUSIONS

Accelerometer-triggered electrical stimulation to augment task training for the hemiplegic arm is feasible and may improve functional ability and quality of life which may be maintained 12 weeks after treatment. A randomized trial design is required to evaluate efficacy and cost benefit.

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.