To investigate the effectiveness of neuromuscular electrical stimulation (NMES) with or without other interventions in improving lower limb activity after chronic stroke.
To determine the effects of inclusion of deep dry needling into a treatment session following the Bobath concept on spasticity, motor function and postural control after a stroke.
26 patients who had suffered a stroke were randomly assigned to one of two treatment groups: Bobath only, or Bobath plus dry needling. Both groups received a session including strengthening, stretching and reconditioning exercises following the principles of the Bobath concept. Patients in the Bobath plus dry needling group also received a single session of ultrasound-guided dry needling of the tibialis posterior. Spasticity (Modified Modified Ashworth Scale), function (Fugl-Meyer Scale) and stability limits (computerised dynamic posturography using the SMART EquiTest System) were collected before and 10 min after treatment by a blinded assessor. The parameters of the stability limits included movement velocity (MVL), maximum excursion (MXE), end-point excursion (EPE) and directional control (DCL).
A greater number of individuals receiving Bobath plus dry needling exhibited a decrease in spasticity after treatment (P<0.001). Analysis of covariance (ANCOVA) showed that patients receiving Bobath plus dry needling exhibited greater improvements in the balance (0.8, 95% CI 0.2 to 1.4), sensory (1.7, 95% CI 0.7 to 2.7) and range of motion (3.2, 95% CI 2.0 to 4.4) domains of the Fugl-Meyer Scale than those receiving Bobath only. ANCOVA also found that subjects receiving dry needling showed a greater increase in MVL non-affected forward direction, EPE non-affected direction, MXE backward and MXE affected/non-affected, DCL backward and DCL affected backward direction, than those who did not receive it.
The inclusion of deep dry needling into a treatment session following the Bobath concept was effective at decreasing spasticity and improving balance, range of motion and the accuracy of maintaining stability in patients who had experienced a stroke.
The peripheral sensory system is critical to regulating motor plasticity and motor recovery. Peripheral electrical stimulation (ES) can generate constant and adequate sensory input to influence the excitability of the motor cortex. The aim of this proof of concept study was to assess whether ES prior to each hand function training session for eight weeks can better improve neuromuscular control and hand function in chronic stroke individuals and change electroencephalography-electromyography (EEG-EMG) coherence, as compared to the control (sham ES). We recruited twelve subjects and randomly assigned them into ES and control groups. Both groups received 20-minute hand function training twice a week, and the ES group received 40-minute ES on the median nerve of the affected side before each training session. The control group received sham ES. EEG, EMG and Fugl-Meyer Assessment (FMA) were collected at four different time points. The corticomuscular coherence (CMC) in the ES group at fourth weeks was significantly higher (p = 0.004) as compared to the control group. The notable increment of FMA at eight weeks and follow-up was found only in the ES group. The eight-week rehabilitation program that implemented peripheral ES sessions prior to function training has a potential to improve neuromuscular control and hand function in chronic stroke individuals.
Stroke is one of the leading contributing factors to the loss of functional abilities and independence in daily life in adults1. The most common and widely observed impairment following stroke is motor impairment, which can be regarded as a loss or limitation of function in muscle control or movement2,3,4,5. Most stroke survivors later regain the ability to walk independently, but only fewer than 50% of them will have fully recovered upper extremity functions6,7. From a review focusing on motor recovery after stroke, it has been indicated that the recovery of both arm and hand function among subacute and chronic stroke survivors is limited in current neural rehabilitation settings4; therefore, additional management with activating plasticity before or during performing motor training is necessary for better motor recovery.
The fundamental principle of stroke rehabilitation is inducing brain plasticity by sensory or proprioceptive input in order to facilitate motor functions8,9. It has been demonstrated that strong sensory input can induce plastic changes in the motor cortex via direct or indirect pathways10,11,12,13,14,15,16,17. In this case, electrical stimulation (ES) that provides steady and adequate somatosensory input can be an ideal method of stimulating the motor cortex.
Recent studies using functional magnetic resonance imaging (fMRI) or transcranial magnetic stimulation (TMS) suggest that ES on peripheral nerves can increase motor-evoked potential (MEP)18,19,20, increase the active voxel count in the corresponding motor cortex13, and increase blood-oxygen-level dependent (BOLD) signals in fMRI, suggesting peripheral ES induced higher excitability and activation level of cortical neurons21. Since the expansion of the motor cortical area or increase in the excitability of neural circuits is associated with learning new motor skills22,23,24,25,26, clinicians should take advantage and assist patients with stroke on motor tasks training during this period of time. Celnik and colleagues27 found that the hand function of chronic stroke subjects improved immediately after two-hour peripheral nerve stimulation combined with functional training, and the effect lasted for one day. Based on previous studies, the ES that increases corticomuscular excitability may turn out to be an ideal intervention added prior to traditional motor training to “activate” the neural circuit, so that patients may get the most out of the training. According to a recent study that applied single session peripheral ES on post-stroke individuals, the corticomuscular coherence (CMC), which is the synchronization level between EEG and EMG, increased significantly and was accompanied by improvement in the steadiness of force output28.
To our knowledge, however, there is no study investigating the long-term effect of ES combined with functional training on both motor performance and cortical excitability. We targeted the median nerve because its distribution covered the dorsal side of index, middle, and half of ring finger and the palmar side of the first three fingers and half of the ring finger. Besides, median nerve is in charge of the flexion of the first three fingers, which combined they accounts for most of the functional tasks of hand. Therefore, the purpose of this pilot study was to preliminarily evaluate the effect of eight-week ES-combined hand functional training among chronic stroke patients based on CMC and motor performance. We followed up for four weeks after the intervention ceased and examined the lasting effect. We hypothesized that those who received intervention with ES would have better hand function and higher CMC than those who received intervention with sham ES. We also hypothesized that the effect would last for at least four weeks during our follow-up.[…]
UC San Francisco scientists have improved mobility in rats that had experienced debilitating strokes by using electrical stimulation to restore a distinctive pattern of brain cell activity associated with efficient movement. The researchers say they plan to use the new findings to help develop brain implants that might one day restore motor function in human stroke patients.
After a stroke, roughly one-third of patients recover fully, one-third have significant lingering movement problems, and one-third remain virtually paralyzed, said senior author Karunesh Ganguly, MD, PhD, associate professor of neurology and a member of the UCSF Weill Institute for Neurosciences. Even patients who experience partial recovery often continue to struggle with “goal-directed” movements of the arms and hands, such as reaching and manipulating objects, which can be crucial in the workplace and in daily living.
“Our main impetus was to understand how we can develop implantable neurotechnology to help stroke patients,” said Ganguly, who conducts research at the San Francisco VA Health Care System. “There’s an enormous field growing around the idea of neural implants that can help neural circuits recover and improve function. We were interested in trying to understand the circuit properties of an injured brain relative to a healthy brain and to use this information to tailor neural implants to improve motor function after stroke.”
Over the past 20 years, neuroscientists have presented evidence that coordinated patterns of neural activity known as oscillations are important for efficient brain function. More recently, low-frequency oscillations (LFOs)—which were first identified in studies of sleep—have been specifically found to help organize the firing of neurons in the brain’s primary motor cortex. The motor cortex controls voluntary movement, and LFOs chunking the cells’ activity together to ensure that goal-directed movements are smooth and efficient.
In the new study, published in the June 18, 2018 issue of Nature Medicine, the researchers first measured neural activity in rats while the animals reached out to grab a small food pellet, a task designed to emulate human goal-directed movements. They detected LFOs immediately before and during the action, which inspired the researchers to investigate how these activity patterns might change after stroke and during recovery.
To explore these questions, they caused a stroke in the rats that impaired the animals’ movement ability, and found that LFOs diminished. In rats that were able to recover, gradually making faster and more precise movements, the LFOs also returned. There was a strong correlation between recovery of function and the reemergence of LFOs: animals that fully recovered had stronger low-frequency activity than those that partially recovered, and those that didn’t recover had virtually no low-frequency activity at all.
To try to boost recovery, the researchers used electrodes to both record activity and to deliver a mild electrical current to the rats’ brains, stimulating the area immediately surrounding the center of the stroke damage. This stimulation consistently enhanced LFOs in the damaged area and appeared to improve motor function: when the researchers delivered a burst of electricity right before a rat made a movement, the rat was up to 60 percent more accurate at reaching and grasping for a food pellet.
“Interestingly, we observed this augmentation of LFOs only on the trials where stimulation was applied,” said Tanuj Gulati, PhD, a postdoctoral researcher in the Ganguly lab who is co-first author of the study, along with Dhakshin Ramanathan, MD, PhD, now assistant professor of psychiatry at UC San Diego, and Ling Guo, a neuroscience graduate student at UCSF.
“We are not creating a new frequency, we are amplifying the existing frequency,” added Ganguly. “By amplifying the weak low-frequency oscillations, we are able to help organize the task-related neural activity. When we delivered the electrical current in step with their intended actions, motor control actually got better.”
The researchers wanted to know whether their findings might also apply to humans, so they analyzed recordings made from the surface of the brain of an epilepsy patient who had suffered a stroke that had impaired the patient’s arm and hand movements. The recordings revealed significantly fewer LFOs than recordings made in two epilepsy patients who hadn’t had a stroke. These findings suggest that, just like in rats, the stroke had caused a loss of low-frequency activity that impaired the patient’s movement.
Physical therapy is the only treatment currently available to aid stroke patients in their recovery. It can help people who are able to recover neurologically get back to being fully functional more quickly, but not those whose stroke damage is too extensive. Ganguly hopes that electrical brain stimulation can offer a much-needed alternative for these latter patients, helping their brain circuits to gain better control of motor neurons that are still functional. Electrical brain stimulation is already widely used to help patients with Parkinson’s disease and epilepsy, and Ganguly believes stroke patients may be the next to benefit.
Other UCSF contributors to the work included Gray Davidson; April Hishinuma; Seok-Joon Won, PhD, associate adjunct professor of neurology; Edward Chang, MD, professor of neurosurgery and William K. Bowes Jr. Biomedical Investigator; and Raymond Swanson, MD, professor of neurology. They were joined by Robert T. Knight, MD, professor of psychology and neuroscience at UC Berkeley.
The research was supported in part by funding from the National Institute of Neurological Disorders and Stroke; the National Institute of Mental Health; the Agency for Science, Technology, and Research (A*STAR), in Singapore; the U.S. Department of Veterans Affairs, and the Burroughs Wellcome Fund.
Therapeutic benefits of Kinect-based virtual reality (VR) game training in rehabilitation encourage its use to improve motor function.
To assess the effects of Kinect-based VR training on motor recovery of the upper extremity and functional outcomes in patients with chronic stroke.
In this randomized controlled trial, group A received 20 sessions of physical therapy (PT) + 20 sessions of Kinect-based VR training and group B received only 20 sessions of PT. Clinical outcome measures were assessed at baseline and at the end of the treatments. Primary outcome measures that assess stroke patients’ motor function included upper extremity (UE) Fugl-Meyer Assessment (FMA). Secondary outcome measures were Brunnstrom Recovery Stages (BRS), Modified Ashworth Scale (MAS), Box and Block test (BBT), Motricity index (MI), and active range of motion (AROM) measurement.
Statistically significant improvements in game scores (p < 0.05) were observed in group A. In within-group analysis, there were statistically significant improvements in all clinical outcome measures except for the BRS-hand, MAS-distal, and MAS-hand in group A; MAS-(proximal, distal, hand) and BRS-(UE, hand) in group B compared with baseline values. Differences from baseline of FMA, MI, and AROM (except adduction of shoulder and extension of elbow) were greater in group A (p < 0.05).
To conclude, our results suggest that the adjunct use of Kinect-based VR training may contribute to the improvement of UE motor function and AROM in chronic stroke patients. Further studies with a larger number of subjects with longer follow-up periods are needed to establish its effectiveness in neurorehabilitation.
Tele-rehabilitation for stroke survivors has emerged as a promising intervention for remotely supervised administration of physical, occupational, speech, and other forms of therapies aimed at improving motor, cognitive, and neuropsychiatric deficits from stroke.
We aimed to provide an updated systematic review on the efficacy of tele-rehabilitation interventions for recovery from motor, higher cortical dysfunction, and poststroke depression among stroke survivors.
We searched PubMed and Cochrane library from January 1, 1980 to July 15, 2017 using the following keywords: “Telerehabilitation stroke,” “Mobile health rehabilitation,” “Telemedicine stroke rehabilitation,” and “Telerehabilitation.” Our inclusion criteria were randomized controlled trials, pilot trials, or feasibility trials that included an intervention group that received any tele-rehabilitation therapy for stroke survivors compared with a control group on usual or standard of care.
This search yielded 49 abstracts. By consensus between 2 investigators, 22 publications met the criteria for inclusion and further review. Tele-rehabilitation interventions focused on motor recovery (n = 18), depression, or caregiver strain (n = 2) and higher cortical dysfunction (n = 2). Overall, tele-rehabilitation interventions were associated with significant improvements in recovery from motor deficits, higher cortical dysfunction, and depression in the intervention groups in all studies assessed, but significant differences between intervention versus control groups were reported in 8 of 22 studies in favor of tele-rehabilitation group while the remaining studies reported nonsignificant differences.
This updated systematic review provides evidence to suggest that tele-rehabilitation interventions have either better or equal salutary effects on motor, higher cortical, and mood disorders compared with conventional face-to-face therapy.
Copyright © 2018 National Stroke Association. All rights reserved.
Two inertial measurement units (IMU) are stuck to my wrists and forearms, tracking the orientation of my arms, while the EMG monitors my electrical impulses and peripheral nerve activity.
Dr. Sook-Lei Liew, Director of USC’s Neural Plasticity and Neurorehabilitation Laboratory, and Julia Anglin, Research Lab Supervisor and Technician, wait to record my baseline activity and observe a monitor with a representation of my real arm and a virtual limb. I see the same image from inside the Rift.
“Ready?” asks Dr. Liew. “Don’t move—or think.”
I stay still, close my eyes, and let my mind go blank. Anglin records my baseline activity, allowing the brain-machine interface to take signals from the EEG and EMG, alongside the IMU, and use that data to inform an algorithm that drives the virtual avatar hand.
“Now just think about moving your arm to the avatar’s position,” says Dr. Liew.
I don’t move a muscle, but think about movement while looking at the two arms on the screen. Suddenly, my virtual arm moves toward the avatar appendage inside the VR world.
Something happened just because I thought about it! I’ve read tons of data on how this works, even seen other people do it, especially inside gaming environments, but it’s something else to experience it for yourself.
“Very weird isn’t it?” says David Karchem, one of Dr. Liew’s trial patients. Karchem suffered a stroke while driving his car eight years ago, and has shown remarkable recovery using her system.
“My stroke came out of the blue and it was terrifying, because I suddenly couldn’t function. I managed to get my car through an intersection and call the paramedics. I don’t know how,” Karchem says.
He gets around with a walking stick today, and has relatively normal function on the right side of his body. However, his left side is clearly damaged from the stroke. While talking, he unwraps surgical bandages and a splint from his left hand, crooked into his chest, to show Dr. Liew the progress since his last VR session.
As a former software engineer, Karchem isn’t fazed by using advanced technology to aid the clinical process. “I quickly learned, in fact, that the more intellectual and physical stimulation you get, the faster you can recover, as the brain starts to fire. I’m something of a lab rat now and I love it,” he says.
Karchem is participating in Dr. Liew’s REINVENT (Rehabilitation Environment using the Integration of Neuromuscular-based Virtual Enhancements for Neural Training) project, funded by the American Heart Association, under a National Innovative Research Grant. It’s designed to help patients who have suffered strokes reconnect their brains to their bodies.
“My PhD in Occupational Science, with a concentration in Cognitive Neuroscience, focused on how experience changes brain networks,” explains Dr. Liew. “I continued this work as a Postdoctoral Fellow at the National Institute of Neurological Disorders and Stroke at the National Institutes of Health, before joining USC, in my current role, in 2015.
“Our main goal here is to enhance neural plasticity or neural recovery in individuals using noninvasive brain stimulation, brain-computer interfaces and novel learning paradigms to improve patients’ quality of life and engagement in meaningful activities,” she says.
Here’s the science bit: the human putative mirror neuron system (MNS) is a key motor network in the brain that is active both when you perform an action, like moving your arm, and when you simply watch someone else—like a virtual avatar—perform that same action. Dr. Liew hypothesizes that, for stroke patients who can’t move their arm, simply watching a virtual avatar that moves in response to their brain commands will activate the MNS and retrain damaged or neighboring motor regions of the brain to take over the role of motor performance. This should lead to improved motor function.
“In previous occupational therapy sessions, we found many people with severe strokes got frustrated because they didn’t know if they were activating the right neural networks when we asked them to ‘think about moving’ while we physically helped them to do so,” Dr. Liew says. “If they can’t move at all, even if the right neurological signals are happening, they have no biological feedback to reinforce the learning and help them continue the physical therapy to recover.”
For many people, the knowledge that there’s “intent before movement”—in that the brain has to “think” about moving before the body will do so, is news. We also contain a “body map” inside our heads that predicts our spacetime presence in the world (so we don’t bash into things all the time and know when something is wrong). Both of these brain-body elements face massive disruption after a stroke. The brain literally doesn’t know how to help the body move.
What Dr. Liew’s VR platform has done is show patients how this causal link works and aid speedier, and less frustrating, recovery in real life.
She got the idea while geeking out in Northern California one day.
“I went to the Experiential Technology Conference in San Francisco in 2015, and saw demos of intersections of neuroscience and technology, including EEG-based experiments, wearables, and so on. I could see the potential to help our clinical population by building a sensory-visual motor contingency between your own body and an avatar that you’re told is ‘you,’ which provides rewarding sensory feedback to reestablish brain-body signals.
“Inside VR you start to map the two together, it’s astonishing. It becomes an automatic process. We have seen that people who have had a stroke are able to ’embody’ an avatar that does move, even though their own body, right now, cannot,” she says.
Dr. Liew’s system is somewhat hacked together, in the best possible Maker Movement style; she built what didn’t exist and modified what did to her requirements.
“We wanted to keep costs low and build a working device that patients could actually afford to buy. We use Oculus for the [head-mounted display]. Then, while most EEG systems are $10,000 or more, we used an OpenBCI system to build our own, with EMG, for under $1,000.
“We needed an EEG cap, but most EEG manufacturers wanted to charge us $200 or more. So, we decided to hack the rest of the system together, ordering a swim cap from Amazon, taking a mallet and bashing holes in it to match up where the 12 positions on the head electrodes needed to be placed (within the 10-10 international EEG system). We also 3D print the EEG clips and IMU holders here at the lab.
“For the EMG, we use off-the-shelf disposable sensors. This allows us to track the electromyography, if they do have trace muscular activity. In terms of the software platform, we coded custom elements in C#, from Microsoft, and implemented them in the Unity3D game engine.”
Dr. Liew is very keen to bridge the gap between academia and the tech industry; she just submitted a new academic paper with the latest successful trial results from her work for publication. Last year, she spoke at SXSW 2017 about how VR affects the brain, and debuted REINVENT at the conference’s VR Film Festival. It received a “Special Jury Recognition for Innovative Use of Virtual Reality in the Field of Health.”
Going forward, Dr. Liew would like to bring her research to a wider audience.
“I feel the future of brain-computer interfaces splits into adaptive, as with implanted electrodes, and rehabilitative, which is what we work on. What we hope to do with REINVENT is allow patients to use our system to re-train their neural pathways, [so they] eventually won’t need it, as they’ll have recovered.
“We’re talking now about a commercial spin-off potential. We’re able to license the technology right now, but, as researchers, our focus, for the moment, is in furthering this field and delivering more trial results in published peer-reviewed papers. Once we have enough data we can use machine learning to tailor the system precisely for each patient and share our results around the world.”
If you’re in L.A., Dr. Liew and her team will be participating in the Creating Reality VR Hackathon from March 12-15 at USC. Details here.
To evaluate the mean treatment effect of mirror therapy on motor function of the upper extremity in patients with stroke.
Electronic databases, including the Cochrane Library, PubMed, MEDLINE, Embase and CNKSystematic, were searched for relevant studies published in English between 1 January 2007 and 22 June 2017.
Randomized controlled trials and pilot randomized controlled trials that compared mirror therapy/mirror box therapy with other rehabilitation approaches were selected.
Two authors independently evaluated the searched studies based on the inclusion/exclusion criteria and appraised the quality of included studies according to the criteria of the updated version 5.1.0 of the Cochrane Handbook for Systematic Review of Interventions.
Eleven trials, with a total of 347 patients, were included in the meta-analysis. A moderate effect of mirror therapy (standardized mean difference 0.51, 95% confidence interval (CI) 0.29, 0.73) on motor function of the upper extremity was found. However, a high degree of heterogeneity (χ2 = 25.65, p = 0.004; I2 = 61%) was observed. The heterogeneity decreased a great deal (χ2 = 6.26, p = 0.62; I2 = 0%) after 2 trials were excluded though sensitivity analysis.
Although the included studies had high heterogeneity, meta-analysis provided some evidence that mirror therapy may significantly improve motor function of the upper limb in patients with stroke. Further well-designed studies are needed.
Jaimie Henderson, M.D. is director of the Stanford program in Stereotactic and Functional Neurosurgery, and co-director (with Prof. Krishna Shenoy, PhD) of the Stanford Neural Prosthetics Translational Laboratory (NPTL). His research interests encompass several areas of stereotactic and functional neurosurgery, including frameless stereotactic approaches for therapy delivery to deep brain nuclei; mechanisms of action of deep brain stimulation; cortical physiology and its relationship to normal and pathological movement; neural prostheses; and the development of novel neuromodulatory techniques for the treatment of neurological diseases. During his residency in the early 1990’s, Dr. Henderson was intimately involved with the development of the new field of image-guided surgery. This innovative technology has revolutionized the practice of neurosurgery, allowing for safer and more effective operations with reduced operating time. Dr. Henderson remains one of the world’s foremost experts on the application of image-guided surgical techniques to functional neurosurgical procedures such as the placement of deep brain stimulators for movement disorders, epilepsy, pain, and psychiatric diseases. His work with NPTL focuses on the creation of clinically viable interfaces between the human brain and prosthetic devices to assist people with severe neurological disability.
NIH Neuroscience Series Seminar
For more information go to https://neuroscience.nih.gov/neuroseries/Home.aspx
To investigate the effectiveness of neuromuscular electrical stimulation (NMES) with or without other interventions in improving lower limb activity after chronic stroke.
Electronic databases including PubMed, EMBase, Cochrane Library, PEDro (Physiotherapy Evidence Database) and PsycINFO were searched from the inception to January, 2017.
We selected the randomized controlled trials (RCTs) involving chronic stroke survivors with lower limb dysfunction and comparing NMES or combined with other interventions with control of no electrical-stimulated treatment.
The primary outcome was defined as lower limb motor function, and the secondary outcomes included gait speed, Berg Balance scale, Timed Up and Go, Six-Minute Walk Test, Modified Ashworth Scale and Range of Motion .
Twenty-one RCTs involving 1,481 participants were identified from 5,759 retrieved articles. Pooled analysis showed that NMES had a moderate but statistically significant benefits on lower limb motor function (SMD 0.42, 95% CI 0.26 to 0.58), especially when NMES combined with other interventions or treatment time within either 6 or 12 weeks. NMES also had significant benefits on gait speed, balance, spasticity and range of motion but had no significant difference in walking endurance after NMES.
NMES combined with or without other interventions has beneficial effects in lower limb motor function in chronic stroke survivors. These data suggest that NMES should be a promising therapy to apply in chronic stroke rehabilitation to improve the capability of lower extremity in performing activities.