The efficacy of electrical stimulation in reducing the post-stroke spasticity: a randomized controlled study

Application of neuromuscular electrical stimulation during immobilization of extremities for musculoskeletal conditions: A scoping review

BACKGROUND

Neuromuscular electrical stimulation (NMES) is effective at improving recovery after periods of disuse. It is unclear if NMES can be applied during periods of immobilization for musculoskeletal conditions to mitigate resulting impairments from disuse. The aim of this scoping review is to describe the state of the literature applying NMES during immobilization to treat upper and lower extremity musculoskeletal conditions.

METHODS

A literature search was conducted in October 2023 combining keywords related to "neuromuscular electrical stimulation", "musculoskeletal", and "immobilization" in Pubmed, Scopus, CINAHL, and Proquest Dissertations and Thesis with an English filter. Articles were included if an upper or lower extremity was immobilized during the NMES application and NMES was applied with surface electrodes. Articles were excluded if NMES was applied outside of the immobilization period, participants had a neurological condition that could impair neuromotor pathways, and/or electrical stimulation was applied invasively. Data extracted included study design, sample characteristics, immobilization protocol, intervention, stimulation parameters, outcome measures, and results. The Joanna Briggs Institute (JBI) Critical Appraisal Tools for Cohort Studies was used to assess quality for all included studies.

RESULTS

Six studies with 127 participants were included. The musculoskeletal conditions addressed were anterior cruciate ligament repair and tibia fracture. Immobilization procedures maintain knee flexion between 10 and 45° for four to six weeks. NMES was applied through holes cut in the casts. NMES duration ranged from 40 minutes to 8 hours a day with an alternating current ramping up over 0.4 to 4 seconds (s), the contraction duration between two and 20 s, and rest times between five and 50 s. NMES application improved quadriceps atrophy and strength outcomes in four studies.

DISCUSSION

The body of literature is limited to two patient populations, only a small sample of cohort studies, physiological outcomes, and all studies were published before 1989. The models used in these studies are outdated, so new models (i.e. distal radius fracture) are proposed to investigate NMES application during immobilization in musculoskeletal populations. This study highlights a substantial gap in the literature and that further investigation into NMES application during immobilization for musculoskeletal conditions is warranted.

The Effect of Neuromuscular Electrical Nerve Stimulation in the Management of Post-stroke Spasticity: A Scoping Review

Stroke is a cerebrovascular disorder characterized by the sudden onset of symptoms and clinical signs caused by either vascular infraction or hemorrhage. One of the main symptoms in the majority of post-stroke patients is spasticity. The main therapeutic options of spasticity in post-stroke patients include pharmacological interventions, rehabilitation techniques, and surgery. This review aims to explore the effectiveness of Neuromuscular Electrical Stimulation (NMES) for post-stroke spastic hemiparetic limb (upper and lower). Thorough research of the PubMed Medline database was performed. Records were limited to clinical studies published between 01/01/2010 and 01/01/2022. The results were screened by the authors in pairs. The search identified 26 records. After screening, nine records met the inclusion-exclusion criteria and were assessed. There were seven studies for spastic upper limbs and two for spastic lower limbs. The approaches investigated the effectiveness of electrical stimulation on post-stroke spastic upper or lower limb. Spasticity was measured through the modified Ashworth scale (MAS) and electromyographic recordings (EMG). In most cases, spasticity was decreased for at least two weeks post-intervention. In conclusion, NMES can be used either solo or in combination with different physical therapy modalities in order to produce optimal results, taking into consideration the specific needs and limitations of each individual patient. Based on the existing literature, as well as the limitations of the included studies, the authors believe that future studies on the subject of NMES in the management of post-stroke spasticity should focus on carefully examining each electrical parameter.

Post-Stroke Treatment with Neuromuscular Functional Electrostimulation of Antagonistic Muscles and Kinesiotherapy Evaluated with Electromyography and Clinical Studies in a Two-Month Follow-Up

The aim of this study was to determine the sustained influence of personalized neuromuscular functional electrical stimulation (NMFES) combined with kinesiotherapy (mainly, proprioceptive neuromuscular facilitation (PNF)) on the activity of muscle motor units acting antagonistically at the wrist and the ankle in a large population of post-stroke patients. Clinical evaluations of spasticity (Ashworth scale), manual muscle testing (Lovett scale), and surface electromyography recordings at rest (rEMG) and during attempts of maximal muscle contraction (mcEMG) were performed three times in 120 post-stroke patients (T0: up to 7 days after the incidence; T1: after 21 days of treatment; T2: after 60 days of treatment). Patients (N = 120) were divided into two subgroups-60 patients received personalized NMFES and PNF treatment (NMFES+K), and the other 60 received only PNF (K). The NMFES+K therapy resulted in a decrease in spasticity and an increase in muscle strength of mainly flexor muscles, in comparison with the K group. A positive correlation between the increase of rEMG amplitudes and high Ashworth scale scores and a positive correlation between low amplitudes of mcEMG and low Lovett scale scores were found in the wrist flexors and calf muscles on the paretic side. Negative correlations were found between the rEMG and mcEMG amplitudes in the recordings. The five-grade alternate activity score of the antagonists' actions improved in the NMFES+K group. These improvements in the results of controlled NMFES treatment combined with PNF in patients having experienced an ischemic stroke, in comparison to the use of kinesiotherapy alone, might justify the application of conjoined rehabilitation procedures based on neurophysiological approaches. Considering the results of clinical and neurophysiological studies, we suppose that NMFES of the antagonistic muscle groups acting at the wrist and the ankle may evoke its positive effects in post-stroke patients by the modulation of the activity more in the spinal motor centers, including the level of Ia inhibitory neurons, than only at the muscular level.

Electroneurographic Evaluation of Neural Impulse Transmission in Patients after Ischemic Stroke Following Functional Electrical Stimulation of Antagonistic Muscles at Wrist and Ankle in Two-Month Follow-Up

The available data from electroneurography (ENG) studies on the transmission of neural impulses in the motor fibers of upper and lower extremity nerves following neuromuscular functional electrical stimulation (NMFES) combined with kinesiotherapy in post-stroke patients during sixty-day observation do not provide convincing results. This study aims to compare the effectiveness of an NMFES of antagonistic muscle groups at the wrist and ankle and kinesiotherapy based mainly on proprioceptive neuromuscular facilitation (PNF). An ENG was performed once in a group of 60 healthy volunteers and three times in 120 patients after stroke (T0, up to 7 days after the incident; T1, after 21 days of treatment; and T2, after 60 days of treatment); 60 subjects received personalized NMFES and PNF treatment (NMFES+K), while the other 60 received only PNF (K). An ENG studied peripheral (M-wave recordings), C8 and L5 ventral root (F-wave recordings) neural impulse transmission in the peroneal and the ulnar nerves on the hemiparetic side. Both groups statistically differed in their amplitudes of M-wave recording parameters after peroneal nerve stimulation performed at T0 and T2 compared with the control group. After 60 days of treatment, only the patients from the NMFES+K group showed significant improvement in M-wave recordings. The application of the proposed NMFES electrostimulation algorithm combined with PNF improved the peripheral neural transmission in peroneal but not ulnar motor nerve fibers in patients after ischemic stroke. Combined kinesiotherapy and safe, personalized, controlled electrotherapy after stroke give better results than kinesiotherapy alone.

The role of electrical stimulation for rehabilitation and regeneration after spinal cord injury

Electrical stimulation is used to elicit muscle contraction and can be utilized for neurorehabilitation following spinal cord injury when paired with voluntary motor training. This technology is now an important therapeutic intervention that results in improvement in motor function in patients with spinal cord injuries. The purpose of this review is to summarize the various forms of electrical stimulation technology that exist and their applications. Furthermore, this paper addresses the potential future of the technology.

Neuromuscular electrical stimulation for motor recovery in pediatric neurological conditions: a scoping review

AIM

To explore the breadth of pediatric neurological conditions for which neuromuscular electrical stimulation (NMES) has been studied.

METHOD

Databases (PubMed, Google Scholar, Scopus, and Embase) were searched from 2000 to 2020, using the search terms 'neuromuscular electrical stimulation' OR 'functional electrical stimulation' with at least one of the words 'pediatric OR child OR children OR adolescent', and without the words 'dysphagia OR implanted OR enuresis OR constipation'. Articles focused on adults or individuals with cerebral palsy (CP) were excluded.

RESULTS

Thirty-five studies met the inclusion criteria, with a total of 353 pediatric participants (293 unique participants; mean age 7y 4mo, range 1wk-38y). NMES was applied in a range of pediatric conditions other than CP, including stroke, spinal cord injury, myelomeningocele, scoliosis, congenital clubfoot, obstetric brachial plexus injury, genetic neuromuscular diseases, and other neuromuscular conditions causing weakness.

INTERPRETATION

All 35 studies concluded that NMES was well-tolerated and most studies suggested that NMES could augment traditional therapy methods to improve strength. Outcome measurements were heterogeneous. Further research on NMES with larger, randomized studies will help clarify its potential to improve physiology and mobility in pediatric patients with neuromuscular conditions. What this paper adds Neuromuscular electrical stimulation (NMES) appears to be tolerated by pediatric patients. NMES shows potential for augmenting recovery in pediatric patients with a range of rehabilitation needs.

Neuromuscular Electrical Stimulation Improves Activities of Daily Living Post Stroke: A Systematic Review and Meta-analysis

Objectives

(1) To elucidate the effectiveness of neuromuscular electrical stimulation (NMES) toward improving activities of daily living (ADL) and functional motor ability post stroke and (2) to investigate the influence of paresis severity and the timing of treatment initiation for the effectiveness of NMES.

Data Sources

PubMed, MEDLINE, Embase, Physiotherapy Evidence Database (PEDro) and Cochrane Library searched for relevant articles from database inception to May 2020.

Study Selection

The inclusion criteria were randomized controlled trials exploring the effect of NMES toward improving ADL or functional motor ability in survivors of stroke. The search identified 6064 potential articles with 20 being included.

Data Extraction

Two independent reviewers conducted the data extraction. Methodological quality was assessed using the PEDro scale and the Cochrane Risk of Bias Tool.

Data Synthesis

Data from 428 and 659 participants (mean age, 62.4 years; 54% male) for outcomes of ADL and functional motor ability, respectively, were pooled in a random-effect meta-analysis. The analysis revealed a significant positive effect of NMES toward ADL (standardized mean difference [SMD], 0.41; 95% CI, 0.14-0.67; P=.003), whereas no effect on functional motor ability was evident. Subgroup analyses showed that application of NMES in the subacute stage (SMD, 0.44; 95% CI, 0.09-0.78; P=.01) and in the upper extremity (SMD, 0.34; 95% CI, 0.04-0.64; P=.02) improved ADL, whereas a beneficial effect was observed for functional motor abilities in patients with severe paresis (SMD, 0.41; 95% CI, 0.12-0.70; P=.005).

Conclusions

The results of the present meta-analysis are indicative of potential beneficial effects of NMES toward improving ADL post stroke, whereas the potential for improving functional motor ability appears less clear. Furthermore, subgroup analyses indicated that NMES application in the subacute stage and targeted at the upper extremity is efficacious for ADL rehabilitation and that functional motor abilities can be positively affected in patients with severe paresis.

Zakaria H, M. Ragab W, Al Awaji NN, Y. Elzanaty M, R. Elserougy H. Therapeutic Efficacy of Transcutaneous Electrical Nerve Stimulation Acupoints on Motor and Neural Recovery of the Affected Upper Extremity in Chronic Stroke: A Sham-Controlled Randomized Clinical Trial

Inability to use the affected upper extremity (UE) in daily activities is a common complaint in stroke patients. The somatosensory system (central and peripheral) is essential for brain reorganization and plasticity. Neuromuscular electrical stimulation is considered an effective modality for improving UE function in stroke patients. The aim of the current study was to determine the therapeutic effects of transcutaneous electrical nerve stimulation (TENS) acupoints on cortical activity and the motor function of the affected UE in chronic stroke patients. Forty male and female patients diagnosed with stroke agreed to join the study. They were randomly assigned to group 1 (G1) and group 2 (G2). G1 received task-specific training (TST) and sham electrical stimulation while G2 received TST in addition to TENS acupoints. Session duration was 80 min. Both groups received 18 sessions for 6 successive weeks, 3 sessions per week. Evaluation was carried out before and after completion of the treatment program. Outcome measures used were the Fugl-Meyer Assessment of the upper extremity (FMA-UE) and the box and block test (BBT) as measures of the motor function of the affected UE. Brain activity of the motor area (C3) in the ipsilesional hemisphere was measured using a quantitative electroencephalogram (QEEG). The measured parameter was peak frequency. It was noted that the motor function of the affected UE improved significantly post-treatment in both groups, while no significant change was reported in the FMA-UE and BBT scores post-treatment in either G1 or G2. On the other hand, the activity of the motor area C3 improved significantly in G2 only, post-treatment, while G1 showed no significant improvement. There was also significant improvement in the activity of the motor area (C3) in G2 compared to G1 post-treatment. The results of the current study indicate that TST only or combined with TENS acupoints can be considered an effective method for improving motor function of the affected UE in chronic stroke patients, both being equally effective. However, TST combined with TENS acupoints proved better in improving brain plasticity in chronic stroke patients.

A randomised clinical trial comparing 35 Hz versus 50 Hz frequency stimulation effects on hand motor recovery in older adults after stroke

More solid data are needed regarding the application of neuromuscular electrical stimulation (NMES) in the paretic hand following a stroke. A randomised clinical trial was conducted to compare the effects of two NMES protocols with different stimulation frequencies on upper limb motor impairment and function in older adults with spastic hemiparesis after stroke. Sixty nine outpatients were randomly assigned to the control group or the experimental groups (NMES with 50 Hz or 35 Hz). Outcome measures included motor impairment tests and functional assessment. They were collected at baseline, after 4 and 8 weeks of treatment, and after a follow-up period. NMES groups showed significant changes (p < 0.05) with different effect sizes in range of motion, grip and pinch strength, the Modified Ashworth Scale, and the muscle electrical activity in the extensors of the wrist. The 35 Hz NMES intervention showed a significant effect on Barthel Index. Additionally, there were no significant differences between the groups in the Box and Block Test. Both NMES protocols proved evidence of improvements in measurements related to hand motor recovery in older adults following a stroke, nevertheless, these findings showed that the specific stimulation frequency had different effects depending on the clinical measures under study.

Pragmatic Solutions for Stroke Recovery and Improved Quality of Life in Low- and Middle-Income Countries-A Systematic Review

Background: Given the limited healthcare resources in low and middle income countries (LMICs), effective rehabilitation strategies that can be realistically adopted in such settings are required. Objective: A systematic review of literature was conducted to identify pragmatic solutions and outcomes capable of enhancing stroke recovery and quality of life of stroke survivors for low- and middle- income countries. Methods: PubMed, HINARI, and Directory of Open Access Journals databases were searched for published Randomized Controlled Trials (RCTs) till November 2018. Only completed trials published in English with non-pharmacological interventions on adult stroke survivors were included in the review while published protocols, pilot studies and feasibility analysis of trials were excluded. Obtained data were synthesized thematically and descriptively analyzed. Results: One thousand nine hundred and ninety six studies were identified while 347 (65.22% high quality) RCTs were found to be eligible for the review. The most commonly assessed variables (and outcome measure utility) were activities of daily living [75.79% of the studies, with Barthel Index (37.02%)], motor function [66.57%; with Fugl Meyer scale (71.88%)], and gait [31.12%; with 6 min walk test (38.67%)]. Majority of the innovatively high technology interventions such as robot therapy (95.24%), virtual reality (94.44%), transcranial direct current stimulation (78.95%), transcranial magnetic stimulation (88.0%) and functional electrical stimulation (85.00%) were conducted in high income countries. Several traditional and low-cost interventions such as constraint-induced movement therapy (CIMT), resistant and aerobic exercises (R&AE), task oriented therapy (TOT), body weight supported treadmill training (BWSTT) were reported to significantly contribute to the recovery of motor function, activity, participation, and improvement of quality of life after stroke. Conclusion: Several pragmatic, in terms of affordability, accessibility and utility, stroke rehabilitation solutions, and outcome measures that can be used in resource-limited settings were found to be effective in facilitating and enhancing post-stroke recovery and quality of life.

Effectiveness of neuromuscular electrical stimulation combined with rehabilitation training for treatment of post-stroke limb spasticity

BACKGROUND

This study aims to systematically explore the effectiveness of neuromuscular electrical stimulation (NMES) combined with rehabilitation training (RT) for the treatment of post-stroke limb spasticity (PSLS).

METHODS

We will search Cochrane Library, MEDILINE, EMBASE, CINAHL, AMED, PsycINFO, WOS, Scopus, OpenGrey, and 4 Chinese databases from inception to the present without language restrictions. We will only consider randomized controlled trial on assessing the effectiveness and safety of NMES combined with RT for the treatment of PSLS. All included randomized controlled trials will be assessed using Cochrane risk of bias tool. Two researchers will independently perform study selection, risk of bias assessment, and data extraction, respectively. Any disagreements will be solved by a third researcher through discussion.

RESULTS

Primary outcome is limb spasticity status. Secondary outcomes comprise of limb function, quality of life, and adverse events.

CONCLUSION

This study will summarize the latest evidence of NMES combined with RT for the treatment of patients with PSLS.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019138900.

A Scoping Review of Neuromuscular Electrical Stimulation to Improve Gait in Cerebral Palsy: The Arc of Progress and Future Strategies

Background: Neuromuscular deficits of children with spastic cerebral palsy (CP) limits mobility, due to muscle weakness, short muscle-tendon unit, spasticity, and impaired selective motor control. Surgical and pharmaceutical strategies have been partially effective but often cause further weakness. Neuromuscular electrical stimulation (NMES) is an evolving technology that can improve neuromuscular physiology, strength, and mobility. This review aims to identify gaps in knowledge to motivate future NMES research. Methods: Research publications from 1990- July 20th 2019 that investigated gait-specific NMES in CP were reviewed using the PubMed and Google Scholar databases. Results were filtered by the National Institute of Neurological Disorder and Stroke common data elements guidelines for CP. The Oxford Centre for Evidence Based Medicine guidelines were used to determine levels of evidence for each outcome. Gait-specific NMES research protocols and trends are described, with implications for future research. Results: Eighteen studies met inclusion criteria, reporting on 212 participants, 162 of whom received NMES while walking, average age of 9.8 years, GMFCS levels I-III. Studies included 4 randomized control trials, 9 cohort studies and 5 case studies. A historical trend emerged that began with experimental multi-channel NMES device development, followed by the commercial development of single-channel devices with inertial sensor-based gait event detection to facilitate ankle dorsiflexion in swing phase. This research reported strong evidence demonstrating improved ankle dorsiflexion kinematics in swing and at initial contact. Improved walking speed, step length, and muscle volume were also reported. However, improvements in global walking scores were not consistently found, motivating a recent return to investigating multi-channel gait-specific NMES applications. Conclusions: Research on single-channel gait-specific NMES found that it improved ankle motion in swing but was insufficient to address more complex gait abnormalities common in CP, such as flexed-knee and stiff-knee gait. Early evidence indicates that multi-channel gait-specific NMES may improve gait patterns in CP, however significantly more research is needed. The conclusions of this review are highly limited by the low level of evidence of the studies available. This review provides a historical record of past work and a technical context, with implications for future research on gait-specific NMES to improve walking patterns and mobility in CP.

Technical development of transcutaneous electrical nerve inhibition using medium-frequency alternating current

Background

Innovative technical approaches to controlling undesired sensory and motor activity, such as hyperalgesia or spasticity, may contribute to rehabilitation techniques for improving neural plasticity in patients with neurologic disorders. To date, transcutaneous electrical stimulation has used low frequency pulsed currents for sensory inhibition and muscle activation. Yet, few studies have attempted to achieve motor nerve inhibition using transcutaneous electrical stimulation. This study aimed to develop a technique for transcutaneous electrical nerve inhibition (TENI) using medium-frequency alternating current (MFAC) to suppress both sensory and motor nerve activity in humans.

Methods

Surface electrodes were affixed to the skin of eight young adults to stimulate the median nerve. Stimulation intensity was increased up to 50% and 100% of the pain threshold. To identify changes in sensory perception by transcutaneous MFAC (tMFAC) stimulation, we examined tactile and pressure pain thresholds in the index and middle fingers before and after stimulation at 10 kHz. To demonstrate the effect of tMFAC stimulation on motor inhibition, stimulation was applied while participants produced flexion forces with the index and middle fingers at target forces (50% and 90% of MVC, maximum voluntary contraction).

Results

tMFAC stimulation intensity significantly increased tactile and pressure pain thresholds, indicating decreased sensory perception. During the force production task, tMFAC stimulation with the maximum intensity immediately reduced finger forces by ~ 40%. Finger forces recovered immediately after stimulation cessation. The effect on motor inhibition was greater with the higher target force (90% MVC) than with the lower target (50% MVC). Also, higher tMFAC stimulation intensity provided a greater inhibition effect on both sensory and motor nerve activity.

Conclusion

We found that tMFAC stimulation immediately inhibits sensory and motor activity. This pre-clinical study demonstrates a novel technique for TENI using MFAC stimulation and showed that it can effectively inhibit both sensory perception and motor activity. The proposed technique can be combined with existing rehabilitation devices (e.g., a robotic exoskeleton) to inhibit undesired sensorimotor activities and to accelerate recovery after neurologic injury.

Investigating Muscle Function After Stroke Rehabilitation with 31P-MRS: A Preliminary Study

BACKGROUND New evidence reveals significant metabolic changes in skeletal muscle after stroke. However, it is unknown if 31P magnetic resonance spectroscopy (31P-MRS) can evaluate these metabolic changes. Our objective here was to investigate: (a) if muscle energy metabolism changes in the affected side; (b) if muscle energy metabolism changes after rehabilitation; and (c) if energy metabolism measured by 31P-MRS can reflect changes in the Modified Modified Ashworth Scale (MMAS) and Fugl-Meyer assessment-lower extremity (FMA-LE) scores after rehabilitation. MATERIAL AND METHODS We enrolled 13 patients with stroke symptoms and hemiplegia. Lower-limb motor status on the affected side was evaluated by FMA-LE and MMAS. The 31P-MRS measures included phosphocreatine (PCr), inorganic phosphate (Pi), PCr/Pi, and pH. We statistically compared these measures in the affected and unaffected lower leg muscles before rehabilitation and after rehabilitation on the affected side. Spearman correlational analyses was performed to determine correlations between change in energy metabolism and change in FMA-LE score and MMAS score after rehabilitation. RESULTS PCr and PCr/Pi were significantly lower in the affected muscle compared to the unaffected muscle; however, there were no significant differences in Pi or pH. After rehabilitation, PCr, Pi, PCr/Pi, and pH did not significantly change. However, FMA-LE and MMAS score improved significantly after rehabilitation. Changes in energy metabolism measured by 31P-MRS had no correlation with FMA-LE change after rehabilitation. However, changes in PCr and PCr/Pi were correlated with change in MMAS score after rehabilitation. CONCLUSIONS 31P-MRS can evaluate changes in muscle energy metabolism in patients with stroke. PCr measured by 31P-MRS can reflect changes in MMAS after rehabilitation.

The Feasibility of Functional Electrical Stimulation to Improve Upper Extremity Function in a Two-year-old Child with Perinatal Stroke: A Case Report

AIMS

To evaluate the effectiveness and feasibility (i.e. tolerability, adherence) of functional electrical stimulation (FES) for the upper extremity (UE) in a two-year-old child with perinatal stroke.

METHODS

Forty hours of FES over eight weeks was prescribed. FES to the hemiplegic triceps, extensor carpi radialis longus and brevis, extensor carpi ulnaris and extensor digitorum was timed with reaching during play. Assessments were performed before, during, and two months post-intervention. UE function (Melbourne Assessment 2 (MA2), Assisting Hand Assessment (AHA)) and spasticity (Modified Tardieu with electrogoniometry and electromyography) were measured. The mother completed a semi-structured interview post-intervention. Descriptive statistics were used for adherence and UE measures. A repeated-measures ANOVA compared Modified Tardieu parameters (e.g. catch angle) over time. Conventional content analysis was used for the interview data.

RESULTS

The child completed 39.2/40 hours. Immediately post-intervention, improvements were observed on MA2's Range of Motion subscale and catch angle (Modified Tardieu, p < 0.001). Two months post-intervention, improvements were observed on MA2's Accuracy and Fluency subscales. No change in AHA score occurred. Three themes emerged from the interview: (1) Ingredients for program success; (2) Information about the FES device; and (3) The child's response.

CONCLUSIONS

UE FES was feasible in a two-year-old child with hemiplegia.

Review of devices used in neuromuscular electrical stimulation for stroke rehabilitation

Neuromuscular electrical stimulation (NMES), specifically functional electrical stimulation (FES) that compensates for voluntary motion, and therapeutic electrical stimulation (TES) aimed at muscle strengthening and recovery from paralysis are widely used in stroke rehabilitation. The electrical stimulation of muscle contraction should be synchronized with intended motion to restore paralysis. Therefore, NMES devices, which monitor electromyogram (EMG) or electroencephalogram (EEG) changes with motor intention and use them as a trigger, have been developed. Devices that modify the current intensity of NMES, based on EMG or EEG, have also been proposed. Given the diversity in devices and stimulation methods of NMES, the aim of the current review was to introduce some commercial FES and TES devices and application methods, which depend on the condition of the patient with stroke, including the degree of paralysis.

Effect of electrical stimulation as an adjunct to botulinum toxin type A in the treatment of adult spasticity: a systematic review

OBJECTIVE

To investigate whether electrical stimulation (ES) as an adjunct to BTX-A boosts botulinum activity and whether the combined therapeutic procedure is more effective than BTX-A alone in reducing spasticity in adult subjects.

DATA SOURCES

A search was conducted in PubMed, EMBASE, Cochrane Central Register, and CINAHL from January 1966 to January 2016.

STUDY SELECTION

Only randomized controlled studies (RCT) involving the combination of BTX-A and ES were considered. RCTs were excluded if BTX plus ES was investigated in animals or healthy subjects; certain techniques were used as an adjunct to BTX-A, but ES was not used; BTX-A or ES were compared but were not used in combination. ES was divided into neuromuscular stimulation (NMS), functional electrical stimulation (FES), and transcutaneous electrical nerve stimulation (TENS). Two authors independently screened all search results and reviewed study characteristics using the Physiotherapy Evidence Database (PEDro) scale.

RESULTS

Fifteen RCTs were pinpointed and nine studies were included. Trials varied in methodological quality, size, and outcome measures used. ES was used in the form of NMS and FES in seven and two studies, respectively. No study investigating BTX-A plus TENS was found. BTX-A plus ES produced significant reduction in spasticity on the Ashworth Scale (AS) and on the modified AS in seven studies, but only four showed high quality on the PEDro scale. Significant reduction in compound muscular action potential (CMAP) amplitude was detected after BTX-A plus ES in two studies.

CONCLUSIONS

ES as an adjunctive therapy to BTX-A may boost BTX-A action in reducing adult spasticity, but ES variability makes it difficult to recommend the combined therapy in clinical practice. Implications for rehabilitation Electrical stimulation (ES) as adjunct to botulinum toxin type A (BTX-A) injections may boost neurotoxin action in treating adult spasticity. Given the variability of ES characteristics and the paucity of high-quality trials, it is difficult to support definitively the use of BTX-A plus ES to potentiate BTX-A effect in clinical practice. A vast array of rehabilitation interventions combined with BTX-A have been provided in reducing spasticity, but the present evidence is not sufficient to recommend any combined therapeutic strategy.

Modulation of spinal inhibitory reflexes depends on the frequency of transcutaneous electrical nerve stimulation in spastic stroke survivors

Neurophysiological studies in healthy subjects suggest that increased spinal inhibitory reflexes from the tibialis anterior (TA) muscle to the soleus (SOL) muscle might contribute to decreased spasticity. While 50 Hz is an effective frequency for transcutaneous electrical nerve stimulation (TENS) in healthy subjects, in stroke survivors, the effects of TENS on spinal reflex circuits and its appropriate frequency are not well known. We examined the effects of different frequencies of TENS on spinal inhibitory reflexes from the TA to SOL muscle in stroke survivors. Twenty chronic stroke survivors with ankle plantar flexor spasticity received 50-, 100-, or 200-Hz TENS over the deep peroneal nerve (DPN) of the affected lower limb for 30 min. Before and immediately after TENS, reciprocal Ia inhibition (RI) and presynaptic inhibition of the SOL alpha motor neuron (D1 inhibition) were assessed by adjusting the unconditioned H-reflex amplitude. Furthermore, during TENS, the time courses of spinal excitability and spinal inhibitory reflexes were assessed via the H-reflex, RI, and D1 inhibition. None of the TENS protocols affected mean RI, whereas D1 inhibition improved significantly following 200-Hz TENS. In a time-series comparison during TENS, repeated stimulation did not produce significant changes in the H-reflex, RI, or D1 inhibition regardless of frequency. These results suggest that the frequency-dependent effect of TENS on spinal reflexes only becomes apparent when RI and D1 inhibition are measured by adjusting the amplitude of the unconditioned H-reflex. However, 200-Hz TENS led to plasticity of synaptic transmission from the antagonist to spastic muscles in stroke survivors.

Effects of Brain-Computer Interface-controlled Functional Electrical Stimulation Training on Shoulder Subluxation for Patients with Stroke: A Randomized Controlled Trial

The purpose of this study was to investigate the effects of brain-computer interface (BCI)-controlled functional electrical stimulation (FES) training on shoulder subluxation of patients with stroke. Twenty subjects were randomly divided into two groups: the BCI-FES group (n = 10) and the FES group (n = 10). Patients in the BCI-FES group were administered conventional therapy with the BCI-FES on the shoulder subluxation area of the paretic upper extremity, five times per week during 6 weeks, while the FES group received conventional therapy with FES only. All patients were assessed for shoulder subluxation (vertical distance, VD; horizontal distance, HD), pain (visual analogue scale, VAS) and the Manual Function Test (MFT) at the time of recruitment to the study and after 6 weeks of the intervention. The BCI-FES group demonstrated significant improvements in VD, HD, VAS and MFT after the intervention period, while the FES group demonstrated significant improvements in HD, VAS and MFT. There were also significant differences in the VD and two items (shoulder flexion and abduction) of the MFT between the two groups. The results of this study suggest that BCI-FES training may be effective in improving shoulder subluxation of patients with stroke by facilitating motor recovery. Copyright © 2016 John Wiley & Sons, Ltd.

Effects of Electrical Stimulation in Spastic Muscles After Stroke

Background and Purpose—

Neuromuscular electric stimulation (NMES) has been used to reduce spasticity and improve range of motion in patients with stroke. However, contradictory results have been reported by clinical trials. A systematic review of randomized clinical trials was conducted to assess the effect of treatment with NMES with or without association to another therapy on spastic muscles after stroke compared with placebo or another intervention.

Methods—

We searched the following electronic databases (from inception to February 2015): Medline (PubMed), EMBASE, Cochrane Central Register of Controlled Trials and Physiotherapy Evidence Database (PEDro). Two independent reviewers assessed the eligibility of studies based on predefined inclusion criteria (application of electric stimulation on the lower or upper extremities, regardless of NMES dosage, and comparison with a control group which was not exposed to electric stimulation), excluding studies with <3 days of intervention. The primary outcome extracted was spasticity, assessed by the Modified Ashworth Scale, and the secondary outcome extracted was range of motion, assessed by Goniometer.

Results—

Of the total of 5066 titles, 29 randomized clinical trials were included with 940 subjects. NMES provided reductions in spasticity (−0.30 [95% confidence interval, −0.58 to −0.03], n=14 randomized clinical trials) and increase in range of motion when compared with control group (2.87 [95% confidence interval, 1.18–4.56], n=13 randomized clinical trials) after stroke.

Conclusions—

NMES combined with other intervention modalities can be considered as a treatment option that provides improvements in spasticity and range of motion in patients after stroke.

Clinical Trial Registration Information—

URL: http://www.crd.york.ac.uk/PROSPERO . Unique identifier: CRD42014008946.

Effects of a 12-hour neuromuscular electrical stimulation treatment program on the recovery of upper extremity function in sub-acute stroke patients: a randomized controlled pilot trial

[Purpose] This study investigated the effects of a 12-hour neuromuscular electrical stimulation program in the evening hours on upper extremity function in sub-acute stroke patients. [Subjects and Methods] Forty-five subjects were randomized to one of three groups: 12-hour neuromuscular electrical stimulation group (n=15), which received 12 hours of neuromuscular electrical stimulation and conventional rehabilitation for the affected upper extremity; neuromuscular electrical stimulation group (n=15), which received 30 min of neuromuscular electrical stimulation and conventional rehabilitation; and control group (n=15), which received conventional rehabilitation only. The Fugl-Meyer assessment, Action Research Arm Test, and modified Ashworth scale were used to evaluate the effects before and after intervention, and 4 weeks later. [Results] The improvement in the distal (wrist-hand) components of the Fugl-Meyer assessment and Action Research Arm Test in the 12-hour neuromuscular electrical stimulation group was more significant than that in the neuromuscular electrical stimulation group. No significant difference was found between the two groups in the proximal component (shoulder-elbow) of the Fugl-Meyer assessment. [Conclusion] The 12-hour neuromuscular electrical stimulation group achieved better improvement in upper extremity motor function, especially in the wrist-hand function. This alternative therapeutic approach is easily applicable and can be used in stroke patients during rest or sleep.

Standing with electrical stimulation and splinting is no better than standing alone for management of ankle plantarflexion contractures in people with traumatic brain injury: a randomised trial

QUESTION

Is a combination of standing, electrical stimulation and splinting more effective than standing alone for the management of ankle contractures after severe brain injury?

DESIGN

A multi-centre randomised trial with concealed allocation, assessor blinding and intention-to-treat analysis.

PARTICIPANTS

Thirty-six adults with severe traumatic brain injury and ankle plantarflexion contractures.

INTERVENTION

All participants underwent a 6-week program. The experimental group received tilt table standing, electrical stimulation and ankle splinting. The control group received tilt table standing alone.

OUTCOME MEASURES

The primary outcome was passive ankle dorsiflexion with a 12Nm torque. Secondary outcomes included: passive dorsiflexion with lower torques (3, 5, 7 and 9Nm); spasticity; the walking item of the Functional Independence Measure; walking speed; global perceived effect of treatment; and perceived treatment credibility. OUTCOME MEASURES were taken at baseline (Week 0), end of intervention (Week 6), and follow-up (Week 10).

RESULTS

The mean between-group differences (95% CI) for passive ankle dorsiflexion at Week 6 and Week 10 were -3 degrees (-8 to 2) and -1 degrees (-6 to 4), respectively, in favour of the control group. There was a small mean reduction of 1 point in spasticity at Week 6 (95% CI 0.1 to 1.8) in favour of the experimental group, but this effect disappeared at Week 10. There were no differences for other secondary outcome measures except the physiotherapists' perceived treatment credibility.

CONCLUSION

Tilt table standing with electrical stimulation and splinting is not better than tilt table standing alone for the management of ankle contractures after severe brain injury.

TRIAL REGISTRATION

ACTRN12608000637347. [Leung J, Harvey LA, Moseley AM, Whiteside B, Simpson M, Stroud K (2014) Standing with electrical stimulation and splinting is no better than standing alone for management of ankle plantarflexion contractures in people with traumatic brain injury: a randomised trial.Journal of Physiotherapy60: 201-208].

Upper limb rehabilitation following stroke: current evidence and future perspectives

Stroke is a leading cause of disability worldwide, with its risk increasing with age. Upper limb hemiparesis is common and associated with persistent impairments and associated disabilities. Older stroke populations often suffer multiple comorbidities and restoring independence is complex. Recovery of upper limb function can be crucial for individuals to return to independent living and to participate in community life. This review describes upper limb recovery post-stroke, and some of the new therapeutic approaches available to promote recovery. Technologies (including virtual reality and telehealth) offer the opportunity for more home-based therapies, longer programs and greater access to rehabilitation for older individuals. However, the trials continue to exclude older individuals, so acceptability is poorly understood. Upper limb rehabilitation remains a research frontier, which has been energized by new technologies, but is grounded by the basic need to find ways to allow older individuals to recover independence. This paper aims to review the applicability and generalizability of current research to the older stoke survivor. Future research priorities need to be tailored to consider the older mean age of individuals in stroke rehabilitation.

Efficacy of coupling repetitive transcranial magnetic stimulation and physical therapy to reduce upper-limb spasticity in patients with stroke: a randomized controlled trial

OBJECTIVE

To assess the efficacy of inhibitory repetitive transcranial magnetic stimulation (rTMS) for decreasing upper-limb muscle tone after chronic stroke.

DESIGN

A randomized sham-controlled trial with a 4-week follow-up.

SETTING

Research hospital.

PARTICIPANTS

Patients with stroke (N=20) with poststroke upper limb spasticity.

INTERVENTIONS

The experimental group received rTMS to the primary motor cortex of the unaffected side (1500 pulses; 1Hz; 90% of resting motor threshold for the first dorsal interosseous muscle) in 10 sessions, 3d/wk, and physical therapy (PT). The control group received sham stimulation and PT.

MAIN OUTCOME MEASURES

Modified Ashworth scale (MAS), upper-extremity Fugl-Meyer assessment, FIM, range of motion, and stroke-specific quality-of-life scale. All outcomes were measured at baseline, after treatment (postintervention), and at a 4-week follow-up. A clinically important difference was defined as a reduction of ≥1 in the MAS score.

RESULTS

Friedman test revealed that PT is efficient for significantly reducing the upper limb spasticity of patients only when it is associated with rTMS. In the experimental group, 90% of the patients at postintervention and 55.5% at follow-up showed a decrease of ≥1 in the MAS score, representing clinically important differences. In the control group, 30% of the patients at postintervention and 22.2% at follow-up experienced clinically meaningful changes. There were no differences between the groups at any time for any of the other outcome measures, indicating that both groups demonstrated similar behaviors over time for all variables.

CONCLUSIONS

rTMS associated with PT can be beneficial in reducing poststroke spasticity. However, more studies are needed to clarify the clinical changes underlying the reduction in spasticity induced by noninvasive brain stimulations.

Stroke rehabilitation: recent advances and future therapies

Despite advances in the acute management of stroke, a large proportion of stroke patients are left with significant impairments. Over the coming decades the prevalence of stroke-related disability is expected to increase worldwide and this will impact greatly on families, healthcare systems and economies. Effective neuro-rehabilitation is a key factor in reducing disability after stroke. In this review, we discuss the effects of stroke, principles of stroke rehabilitative care and predictors of recovery. We also discuss novel therapies in stroke rehabilitation, including non-invasive brain stimulation, robotics and pharmacological augmentation. Many trials are currently underway, which, in time, may impact on future rehabilitative practice.