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The Effectiveness of Electrical Stimulation Treatment on the Arm in Post-Stroke Patients
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The Effectiveness of Electrical Stimulation Treatment on the Arm in Post-Stroke Patients

By: Rohit Duggaraju

I. Introduction

        A stroke, or cerebrovascular incident, is an extremely common type of brain condition, with around 795,000 cases every year in the United States alone. As one of the top three leading causes of death globally, strokes affect millions of people.1 The three main types of strokes are ischemic strokes, hemorrhagic strokes, and transient ischemic attacks (TIAs) or mini strokes. All three types of strokes occur when the blood supply to a part of the brain is lost, causing a loss of nutrients and oxygen to the neurons in that area. This lack of blood supply can have various causes. During hemorrhagic strokes, a blood vessel breaks, and blood leaks into the brain; with ischemic strokes, the blood vessel is blocked by plaque, dead cells, or other buildups.2 The brain damage brought about by the lack of blood can cause death, upper extremity (UE) issues, spasticity, shoulder subluxation, and muscle spasms. Those who survive stroke can experience partial or complete paralysis of limbs, extreme movement deficits, and more, making it difficult to live normal lives and perform daily tasks. This paper will focus on electrical stimulation as a treatment and how it can help post-stroke patients with muscular and motion problems in the upper limbs.

II. Overview of Electrical Stimulation Treatment

Electrical stimulation (ES) is one of the multiple techniques used to help and support the recovery process after stroke. This treatment stimulates neurons in the nervous system by administering an electrical current artificially. Electrical stimulation is used all over the body for different muscles including the heart and lower and upper extremity muscles.3 For this reason, there are multiple types of electrical stimulation, directed at different areas of the body or administered in different ways. This paper will focus on task-specific electrical stimulation and neuromuscular electrical stimulation (NMES). During NMES, a current is administered through electrodes, which are placed on the affected limb using sticky pads.

When a human voluntarily contracts or moves a muscle, electrical signals are sent from the neurons in the brain to the neurons near the targeted muscle. After a stroke, the communication between the brain and the nervous system can be blocked or disrupted, causing a disconnect between brain and the affected muscle.2 This disruption can result in muscle spasms, a lack of control of the muscle, and other symptoms. Applying a stimulating electrical current from on top of the skin simulates the natural impulse and causes the muscle to contract. However, the stimulated action potential is different from a natural action potential created by a voluntary movement.4 Training combined with this treatment can help reduce the risk of muscle atrophy and keep affected extremities in good condition. Multiple studies found that this combination of training and electrical stimulation leads to better motor control in the long run. Many recent studies are also finding that the combination of electrical stimulation and mental training are successful at improving motor control.

However, motor NMES as a standalone therapy can be used to help patients regain control of limbs by training patients to get used to contracted muscles. The clinical rationale behind motor NMES is to either assist patients with doing certain tasks by strengthening contractions or repetitively stimulate the muscles to passively strengthen them. On top of this treatment, some physical therapists use reciprocal inhibition to help recovery. Reciprocal inhibition occurs in muscle pairs such as the biceps and triceps, where one muscle’s contractions are inhibited to accommodate the contraction of the other. Stimulating one muscle with NMES can help inhibit the other, which can be used to relieve spasticity or abnormal stiffness.5 Another type of electrical stimulation is sensory electrical stimulation, separate from motor electrical stimulation. Sensory electrical stimulation deals more with enhancing neuroplasticity in the brain to aid recovery rather than stimulating the muscle itself. However, this paper only aims to review motor NMES, both cyclic and task-specific. Cyclic NMES is a treatment where electrical stimulation is repetitively administered to contract and strengthen a muscle, while task-specific electrical stimulation is where electrical stimulation is administered to assist with contractions when performing a specific task.

III. Methodology

Relevant studies were found using PubMed and Google Scholar. Search terms included “electrical stimulation,” “stroke,” and “upper limb,” and papers were sorted by randomized controlled trials, systemic reviews, or meta-analyses. Studies were then narrowed down to those published after the year 2000, and those in English. The exclusion criteria for the studies were

lack of standardized tests used to measure results, and sample sizes < or = 15.

Figure 1: PRISMA Diagram showing identification, screening, eligibility, and inclusion of studies.

IV. Literature Review of NMES

This scoping review will aim to measure the effectiveness of electrical stimulation by looking at reported outcome measures, amount of time since stroke event, length of dosage, and the type of electrical stimulation (cyclical or task-specific).

Figure 2: Cyclical Neuromuscular Electrical Stimulation electrodes stuck to arm and hand

From Neurorehab Directory, July 5th, 2016, Best Electrode Placement For Arm and Hand Stroke Rehabilitation,, accessed 08.20.2021.

A. Effectiveness of Cyclical Neuromuscular Electrical Stimulation

Multiple studies have reviewed and measured the effects of cyclical NMES versus task-specific ES. Cyclical NMES aims to strengthen muscles by repeatedly stimulating the muscle and causing large contractions. In contrast, task-specific ES aims to improve the patient’s ability to do a specific task with the arm by assisting with stimulation.

Cyclical NMES (cNMES) effectiveness was studied by 86-13  of the papers reviewed. 38, 10, 12 studied cNMES alone, and 56-7, 9, 11, 13 studied the effectiveness of cNMES plus standard rehabilitation programs. The three studying cNMES alone included a study done by Wilson et al.12, which found a statistically significant within-group improvement in cNMES treated patients from the pretest to 6 months post-treatment in the Fugl-Meyer Assessment Upper Extremity (FMA-ue), Fugl-Meyer Assessment Wrist and Hand (FMA-wh), and modified Arm Motor Ability Test (mAMAT). De Kroon et al.8 had similar results comparing cNMES treated groups post-treatment to baseline but also improvements in grip strength and the Motricity Index. In the third study10, when compared to a placebo group, ES on the ulnar and radial nerves caused significant hand dexterity improvements but did not have a significant effect on pinch strength.10 All of these results imply that cNMES is a viable option for post-stroke patients to regain upper extremity function for up to 6 months.

Five6-7, 9, 11, 13 other studies researched the effectiveness of cNMES plus separate physiotherapy rehab programs. Most of the results from these studies suggest that cNMES treatment in conjunction with standard rehabilitation causes a significant improvement in UE motor control. 46, 9, 11, 13 of the 56-7, 9, 11, 13 studies comparing control groups to cNMES treated groups found statistically significant improvements in the cNMES treatment groups. These improvements were in the Action Research Arm Test (ARAT), FMA-ue, and Motor Activity Log, mainly. In contrast, a study by Church and colleagues showed that 3 months after treatment, the treatment group did worse on the ARAT compared to the placebo group, in shoulder function.7 Due to the contradictions in results between studies, nothing conclusive about the effectiveness of cNMES with standard stroke care can be drawn; however, most of the results suggest that combining cNMES with standard stroke care cause significant improvements compared to controls.

In summary, 7 of the 8 studies examining cNMES treatment, show significant improvement and enhanced recovery of UE function and motor control, in terms of range of motion, pain decrease, and general mobility. One7 out of the 8 studies found negative responses to the treatment in shoulder function. The significant between-group differences, favoring the control group, in the study by Church et al.7, which favor the placebo control group, reflect a need for more studies on NMES affecting shoulder function. Additionally, both Wilson et al.12 and Lin et al.9 had check-ins with tests only up to 6 months post-treatment. These short time frames again reflect the need for a study with a longer time frame to measure the full longevity of cNMES treatment.

B. Effectiveness of Task-Specific Electrical Stimulation

        Nine6, 8, 12, 14-19 studies studied task-specific ES, although in 2 different types.

76, 8, 12, 14-16, 19 of these 96, 8, 12, 14-19 studied Electromyography-triggered NMES (EMG-stim), technology that can sense small electromyographic signals in damaged or affected arms and use them to generate ES signals. The other 217, 18 studied ES combined with regular task-oriented practices, slightly less technologically advanced as EMG-triggered ES.

1. Effectiveness of EMG-Triggered Task-Specific Electrical Stimulation

        EMG-stim is an important technological advancement in the field of ES, and studying its effects on the UE is key to understanding how a limb recovers. 66, 8, 12, 15-19 of the 76, 8, 12, 14-16, 19 EMG-stim studies found significant improvements within treated groups and between groups in the FMA, active range of motion (active ROM), grip strength, Motor Activity Log (MAL), and ARAT grasp/pinch/grip scores.

Contradictions to these positive results favoring EMG-stim treated groups arose in one of the seven studies.14 Comparing EMG-stim to standard stroke care, this study concluded that while EMG-stim is feasible to use for weak-arm post-stroke patients, it does not have a significant positive effect when compared to normal UE-strengthening therapy.14

Also, 26, 16 of the other EMG-stim studies slightly contradicted each other. Boyaci et al. found improvements between groups in the Functional Independence Measure (FIM), while Kirac-Unal et al. found no between-group differences in the FIM. However, these two studies have differences that could cause this discrepancy. One16 focused solely on acute/subacute stroke patients, while the other6 had chronic and subacute patients and had a treatment that was one week shorter (5 sessions less) than the other.

2. Effectiveness of Standard Task-Specific Electrical Stimulation

        The remaining two17-18 studies of the 9 focused solely on regular NMES assisting task-oriented exercises, without EMG technology. In the first study18 by Knutson et al., 3 months after treatment, the treated group improved significantly from the mean pretest in finger extension, FMA, Box and Blocks test (BBT), and AMAT. The second study by Knutson et al.17 worked with 80 patients. 40 patients got task-specific electrical stimulation treatment and had statistically significant improvements within the group in AMAT, FMA, and BBT scores. Both these studies, however, compared two experimental groups to their pretests before treatment but did not compare post-treatment scores to a control group who received no treatment. For this reason, while task-oriented ES is a viable treatment for stroke impaired UE, it cannot conclusively be said that it is a better treatment than regular therapy.

C. Comparing Task-Specific ES Treatment to Cyclical NMES Treatment

        Out of 36, 8, 12 studies that looked into comparing cNMES and task-specific ES, there were no statistically significant differences in UE recovery, motor control, or general function between groups. Across the studies, both groups significantly improved compared to the control and the pre-treatment tests. However, results between both experimental groups did not have any significant differences. Wilson et al. concluded that triggering NMES with EMG signals is not enough to create any significant differences from the cNMES group.12 In conclusion, the results suggest that cNMES and task-specific ES, alone or in conjunction with physiotherapy, both enhance improvement with little to no difference between them.

D. Effectiveness of Electrical Stimulation by Amount of Time Post-Stroke

        Treatment may have different effects based on the acuity of a stroke, and it is important to understand when treatments are most effective to produce the best results for the patients. Recovery time post stroke is usually classified into three categories: acute, sub-acute, and chronic. Acute refers to 24 hours or less since stroke onset, subacute refers to 24 hours - 1 month since onset, and chronic refers to multiple months since stroke onset. 412-13, 17, 19  of the 18 studies examined subjects from all 3 recovery categories, 211,20 studied exclusively acute patients, 58, 10, 18, 21-22 studied exclusively chronic patients, 37, 14, 16 studied early stroke patients (acute and sub-acute), 26, 9 studied only sub-acute and chronic patients, and 215, 23 studied only acute and chronic patients.

1. Effectiveness of Electrical Stimulation on acute stroke patients

        Both of the RCTs11, 20 examining exclusively acute patients found significant between-group differences favoring the treated group. However, Malhotra et al. could not conclusively determine the effect of cNMES on muscle contractures and found no significant improvement in muscle stiffness.11 Also, the study by Church and colleagues is notable because, though the study included acute and subacute patients, the treatment group performed worse than the placebo group. The authors could not recommend NMES as a treatment for shoulder motor control issues.7 Due to these differences in results in acute stroke patients a conclusion about the effectiveness of NMES cannot be made.

2. Effectiveness of Electrical Stimulation on sub-acute stroke patients

There was not a study that exclusively focused on studying sub-acute stroke patients, but results and similarities between groups come up in the 56-7, 9, 14, 16 papers that studied both early stroke patients and sub-acute and chronic patients. 46, 9, 14, 16 out of 56-7, 9, 14, 16 of these studies found statistically significant improvements in treatment groups, be it cNMES alone or with physiotherapy. However, due to the study by Church et al. showing that acute and subacute subjects show a decrease in shoulder function after treatment, it is not possible to draw a clear conclusion about the treatment’s effects.7

3. Effectiveness of Electrical Stimulation on chronic stroke patients

In chronic patients, all 5 studies found statistically significant improvements in UE function in treated groups, with task-specific ES, cNMES, and both combined with physiotherapy.8, 10, 18, 21-22 Studies that examined sub-acute & chronic patients and acute & chronic patients also found positive effects of the treatment on all treated patients. From the studies reviewed, NMES treatments are viable for use in chronic stroke patients.

4. Comparing Effectiveness of Electrical Stimulation in the three stages of recovery

        Comparing the effectiveness of NMES on patients in each stage of recovery can be done by examining the results from studies that included all 3 stages. Wilson and colleagues commented on the differences between chronic, acute, and subacute patients, mentioning that there was no evidence that the stage of recovery changed the response to the patient’s treatment.12 Eraifej et al.5 findings slightly contradict this, after reviewing 20 studies. There were more improvements in activities of daily living (ADL) when ES was administered within 2 months post-stroke, and functional electrical stimulation was even shown to have no significant effect on ADL after 1 year post-stroke in 6 of the 20 studies. Adding on to this, Jonsdottir et al. mentioned that patients less than 6 months post-stroke, on average, had better responses to the task-specific ES treatment compared to chronic patients greater than 6 months post-stroke.15

        In conclusion, from Eraifej et al. and Jonsdottir et al., using NMES treatment early in the stroke recovery process seems to have higher benefits than using it later.24, 15 However, Church and colleagues7 found negative responses to treatment in early stroke patients for shoulder function, and Wilson and colleagues12 saw no significant differences in results between acute, sub-acute, and chronic stroke patients. More studies need to be conducted comparing these three groups to draw a conclusion.

E. Effectiveness of Electrical Stimulation based on Length of Dosage

        Studying the effectiveness of NMES based on length of dosage is important to find the most effective amount of ES to administer to achieve successful UE recovery. 320, 22-23 of the papers studied the effect of NMES dosage on UE recovery.

The first study23 conducted by Hsu et al. had four groups, each with 0, 15, 30, and 60 minutes of NMES. At 2-month follow up, a predictor model found that higher, more intense NMES dosage early in rehabilitation leads to higher UE function after stroke.

The study20 by Hsu et al. compared a low NMES group receiving 30 minute sessions and the high NMES group receiving 1 hour sessions. The results between these groups had no significant difference, though. However, the results of this study20 and the predictor variable study23 may not contradict each other as the authors of this study20 state that the difference in dosage (30 minutes versus 60 minutes) may not be enough of a difference to cause significantly different results between groups.

The final study22 comparing dosage lengths of NMES had subjects in either 30 minute, 60 minute, or 120 minute sessions of task-specific therapy assisted with ES. The group that underwent 120 minute sessions was the only group that exhibited significant within group improvement from their baselines.

These results suggest that more intense dosage of NMES may lead to higher UE functional improvement, especially higher dosage in early rehabilitation. However, more studies need to be conducted comparing different dosages with larger differences in dosage between groups to confirm this.

V. Discussion

A. Appropriate / Inappropriate Patients

        Electrical Stimulation therapy can be used, for the most part, on chronic, sub-acute, and acute stroke patients. People of all ages can take the treatment. However, task-specific electrical stimulation does require some participation from the patient, which is not possible in infants and very young children. The equipment is usually available at treatment facilities and hospitals; patients would not be excluded for not having the equipment on hand at home.

Inappropriate patients include patients with electrical devices in their body such as pacemakers, pregnant patients, patients with cancer (especially metastatic), patients with seizures in the past year, and patients with broken, scarred, or wounded skin over the area of ES application. There is no solid evidence that electrical stimulation can affect pregnancy negatively or promote spread of cancer; however, it could be dangerous and is too risky to use on patients with these conditions.

B. Comparison Treatment: Functional Strength Training

        Functional Strength Training (FST) is a treatment used for stroke patients that aims to strengthen muscles through everyday activities and repetitive exercises.25 Electrical stimulation contracts muscles via electrodes to assist with certain tasks or help patients control contractions. These two treatments are similar and different in many ways.

1. Similarities between FST and ES

        Both task-specific electrical stimulation and functional strength training deal with tasks and exercises that the patient must perform. They can both also be used on patients in all stages of acuity.12-13, 14, 17, 24 The treatment itself is similar in some aspects, too, as both are repetitive and progressive. Stimulation needs to be applied repeatedly, as well as functional strength training exercises. As strength is only achieved through muscle overload, training must grow progressively more intense as the recovery process goes on. Electrical stimulation treatment also progresses in terms of dosage and how challenging the tasks are, to ensure improvement in function. Sessions in both also usually range from 30 - 90 minutes for a few weeks, as electrical stimulation being used for more than 90 minutes at a time is impractical for patients usually.25

2. Differences between FST and ES

        Electrical stimulation and FST are different in many ways, as well. Electrical stimulation focuses less on strength training and more on assisting with training, while FST focuses mainly on exercising and overloading muscles for strength gain. Electrical stimulation aims to decrease spasticity, while FST targets mostly function. FST also requires no expensive or unattainable equipment, making it much cheaper than electrical stimulation equipment.25 

        Electrical Stimulation is also slightly less accessible to patients than FST. In terms of exclusion criteria, patients who had past problems with seizures, have cancer, have electrical devices in their bodies, or are pregnant are not allowed into ES treatment. However, FST is much more inclusive as there is no dangerous equipment being used; its criteria include the ability to understand the instructions provided by physiotherapists, and a range of motion that is not very limited.

        Two studies14, 26 compared the effectiveness of strength training to electrical stimulation. Both found no significant differences between FST groups and electrical stimulation groups in terms of strength and function; however, Pantović et al.26 found electrical stimulation group improved slightly more in peak torque.14, 26 As the second study only measures groups based on strength and function measures, it is not possible to conclude that electrical stimulation performed better in terms of decreased spasticity, dexterity, or another category.14 However, the evidence suggests that both therapies are just as good in terms of improving muscle strength.

VI. Conclusion

A. Findings

Electrical Stimulation has been shown to improve UE function6, 8-13, dexterity6, 8, 10, 12, 14, 20-22, range of motion6, 13, 19, performance in activities of daily life (ADLs)9, 13, and decrease spasticity9. These effects were sustained for up to 6 months9, 12, until follow-ups ended. The only unfavorable outcome from the treatment was found by Church and colleagues in shoulder function.7 

The most optimal use of electrical stimulation treatment is still somewhat unclear. No differences were found between task-specific electrical stimulation and neuromuscular electrical stimulation.6, 8, 12  This treatment can also be used on patients in all different stages of acuity, but the most effective time to use treatment is unclear. Higher dosage does seem to improve UE function more22-23, but due to one study finding no significant differences between high and low dosages20, this is unclear. It is also unclear whether combining electrical stimulation with standard stroke therapy improves function more than just electrical stimulation. As almost all studies found significant improvements, this suggests that electrical stimulation is a largely viable treatment for most stroke patients; however, there is a need for more studies to find the optimal dosage, time, and combination of electrical stimulation for the best outcome.

B. Unanswered Questions

1. What is the optimal dosage for electrical stimulation treatment?

The optimal dosage, in terms of length of electrical stimulation sessions, is still unclear. To determine this, a study is needed with 3 separate groups of chronic stroke patients. Chronic stroke patients do not require mandatory stroke rehabilitation care; this removes variables from this study. The control group receives a sham treatment, the second group (low cNMES group) receives 15 minute sessions of cNMES every weekday for 5 weeks, and the third group (high cNMES group) receives 60 minute sessions of cNMES every weekday for 5 weeks.  The patients’ function, dexterity, and spasticity are measured with the FMA, ARAT, and MAS before, halfway through, and 3 months post-treatment. Whichever group shows the most significant improvement at each checkpoint will show the most optimal dosage for this treatment.

2. How long do the effects from electrical stimulation last?

The duration of positive effects from electrical stimulation treatment is still unclear. The longest post-treatment check-up in any of the studies was 6 months. In a study similar to the one above, more check-ups every 3 months up to a year can help elucidate this, but it is difficult to keep patients in the study for such an extended period of time.

VII. Appendices

A. Summary of Evidence

Author, Year, Study Type

Subject Details (number, time post-stroke)


Outcomes (Outcome Measures, Results)

Boyaci et al. 2013, RCT

31, sub-acute and chronic patients

Randomly assigned to either active NMES (n=11), passive NMES (n=10), or control (sham stimulation) (n=10).

Treatment for 45 minutes/5 times per week/3 weeks + neurophysiological training

FMA-ue, self-care FIM, MAL, grip strength, Modified Ashworth scale (MAS).

-Active NMES: improvement in motor function

-Passive NMES: improvement in motor function

-Control: No significant improvement

-Active vs Passive NMES: no significant differences

Church et al. 2006, RCT

176, sub-acute and acute patients

Randomized to either NMES or placebo in addition to stroke unit care.

1 hour/3 times daily/4 weeks

ARAT, Frenchay Arm Test, and the Motricity Index.

Intervention of NMES does not improve shoulder function and can even worsen function.

de Kroon et al. 2008, RCT

22, chronic patients

Randomly assigned either cyclic or EMG-triggered ES for 6 weeks

ARAT, grip strength, FMA, Motricity Index

-Cyclic NMES: had improvements in outcome measures

-EMG-stim: had improvements in outcome measures

-Cyclic vs. EMG-stim: no significant differences

de Kroon et al. 2004, RCT

30, chronic patients

Randomly assigned to NMES on the hand or on the extensors

ARAT, grip strength, motricity index, Ashworth scale, range of motion

-Hand stim group: ARAT 1 point improvement, success rate 8%

-Extensor Stim Group: ARAT 3.3 point improvement, success rate 27%

-Extensor vs Hand stim: no significant differences in ARAT or success rate

Dorsch et al. 2014, RCT

33, sub-acute and acute patients

Randomly assigned either EMG-stim with usual therapy, or just usual therapy.

Treatment 5 times a week/4 weeks

Motor Assessment Scale

EMG-stim + strengthening therapy vs. strengthening therapy: no significant differences in strength (mean between group difference 0/20) or activity (mean between-group difference 1/18)

Hsu et al. 2012, RCT

95, acute and chronic patients

Randomly assigned either 0, 15, 30, or 60 minute sessions. 5 times per week/4 weeks


Regression model found initial motor impairment and lesion location were predictors of recovery, & dosage was important early on in rehab

Hsu et al. 2010, RCT

66, acute patients

Randomly assigned to either low NMES (30 minute sessions), high NMES (60 minute sessions), or control (no treatment).

Daily/4 weeks


-High and low NMES had similar effects, no significant difference.

-Min. 10 hours of NMES helps in rehabilitation

Jonsdottir et al. 2017, RCT

82, acute and chronic patients

Randomly assigned to either task-oriented therapy + electrical stimulation (M-TOT), or conventional rehab + task-oriented therapy (C-TOT).

45 minute sessions/25 sessions

ARAT, FMA-ue, Disability of the Arm Shoulder and Hand questionnaire

M-TOT: 3 pt improvement on ARAT, 4.5 pt improvement on FMA.

C-TOT: 2 pt improvement on ARAT, 3.5 pt improvement on FMA

Larger trend for improvement in M-TOT group, but sample size was not as large as planned

Kirac-Unal et al. 2019, RCT

27, acute, sub-acute, and chronic patients

Randomly assigned to either control (conventional therapy) or treatment (EMG-stim + conventional therapy)

5 weekly sessions/4 weeks


Treated group vs control group: ARAT grasp/grip/pinch scores improved for treated, no differences in FIM

Knutson et al. 2016, RCT

80, chronic patients

Randomly assigned to either cNMES + functional task practice (cNMES group), or ES assisted exercise + functional task practice (ccFES group).

10 sessions per week/12 weeks of electrical stim

20 sessions/12 weeks of functional task practice


cNMES vs ccFES: no differences in FMA or AMAT, but BBT gains were greater in ccFES than cNMES 6-months post (5.5 point between-group difference)

Knutson et al. 2012, RCT

21, chronic patients

Randomly assigned to either ccFES group (ES assisted task practice + functional task exercise) or cNMES group (cNMES + functional task practice)

Daily stim sessions and twice weekly functional task practice


ccFES vs cNMES group: ccFES improved more in all 3 outcome measures, also a significant 28o increase in finger extension in the ccFES group

Lin et al. 2011, RCT

46, sub-acute chronic patients

Randomly assigned to either NMES group or control group.

NMES group: 30 minute sessions/5 days a week/3 weeks + standard rehabilitation

Control group: standard rehabilitation

Modified Barthel Index, Modified Ashworth Scale, FMA-ue

NMES group and control group had significant improvements in all 3 outcome measures after 3 weeks. NMES group significantly improved more than control in all 3.

Liu et al. 2017, RCT

32, chronic patients

Randomly assigned to either a placebo NMES or NMES group.

Treatment administered to ulnar/radial nerves.

Purdue Pegboard Test

ES vs placebo ES:

1 hour of ES is enough to see improvements in arm dexterity and corticomotor excitability, not in placebo.

Malhotra et al. 2013, RCT

90, acute patients

Randomly assigned to either neuromuscular stimulation group or control group

NMES group: 30 mins NMES to wrist & finger extensors + 45 mins physiotherapy/6 weeks

Control group: 45 mins physiotherapy/6 weeks

NMES vs control group:

Treatment stopped development of pain (mean difference in rate of change 0.4 units/week), may have prevented contracture deterioration (mean rate of deterioration -0.5 deg/week), but had no effect on stiffness / spasticity.

Nakipoğlu-Yüzer et al. 2017, RCT

30, acute, aub-acute, and chronic patients

Randomly assigned to either FES group or control group

Control group: no treatment

FES group: functional stimulation applied to wrist and finger extensors

All got standard therapy

Wrist range of movement, the Modified Ashworth Scale, Rivermead Motor Assessment, Brunnstrom hand neurophysiological staging, Barthel Index, and Upper Extremity Function Test

Control vs FES: Range of motion and Barthel Index measures favored the FES group. For Rivermead Motor Assessment, Brunnstrom stages hand, and Upper Extremity Function Test, there was a significant within-group improvement in FES group but not control.

Page et al. 2012, RCT

32, chronic patients

Randomly assigned into either 30 minute, 60 minute, or 120 minute sessions groups. These sessions were with task-specific ES.

Every weekday/8 weeks


-Only the 120 minute session group exhibited significant improvements in 3 measures, except the BBT.


-They also showed the largest improvement of all groups in the BBT, but this was nonsignificant.

Wilson et al. 2016, RCT

122, acute, sub-acute, and chronic patients

Randomly assigned to either cyclic NMES, EMG-stim, or sensory stimulation groups.

40 minute session/2 times per week/8 weeks


Significant within group improvements in all three groups in all three outcome measures. No significant differences between groups in all 3 outcome measures.

Zhou et al. 2018, RCT

90, acute, sub-acute, and chronic patients

Randomly assigned to either NMES, TENS, or control groups.

Both ES groups got treatment to supraspinatus and deltoids.

1 hour/every weekday/4 weeks

Numerical rating scale (NRS), Active/passive ROM, FMA-ue, MAS, Barthel Index (BI), stroke-specific quality of life scale

There were significant improvements in all three groups. Both TENS and NMES improved significantly more than the control, but NMES was significantly better than the TENS group. ROM, FMA, MAS, BI, and SSQOLS for the shoulder were not different among 3 groups.

Eraifej et al. 2017,  Systematic Review




Pollock et al. 2014, Systematic Review




Hunter et al. 2018, RCT

288, acute, sub-acute, and chronic patients

Randomly assigned to conventional physical therapy + either MPT or FST for up to 90 min-a-day/ 5 days a week/6 weeks.


FST vs MPT: Mean change in ARAT 9.7 for FST and 7.9 for MPT - non significant.

Pantović et al. 2015, RCT

15, chronic patients

Randomly assigned to either NMES or resistance training (RT) group.

NMES group: NMES with muscle contraction

RT group: only training

NMES vs RT: NMES is equal or even a better treatment for muscle recovery than RT. Equal in terms of strength, but peak muscle torque increased with NMES more.

VIII. References

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