Kostas Pantremenos

This user hasn't shared any biographical information

Homepage: https://tbirehabilitation.wordpress.com

[Abstract] Fatigue and its’ relationship to physical activity in adolescents and young adults with traumatic brain injury: a cross-sectional study

Physical activity (PA) in patients with traumatic brain injury (TBI) may be impaired leading to secondary health issues and limitations in participation.This study aims to determine the level of PA and its determinants in adolescents and young adults with TBI.Cross-sectional survey study.Outpatient clinic of a rehabilitation centre.Discharged patients aged 12-39 years with a diagnosis of TBI >6 months treated in the rehabilitation centre between 2009-2012.The Activity Questionnaire for Adults and Adolescents (AQuAA) measuring PA, with results dichotomized for meeting or not meeting Dutch recommendations for health enhancing physical activity (D-HEPA) and the Checklist Individual Strength (CIS; range 20- 140, higher scores represent higher levels of fatigue), measuring fatigue, were administered.Fifty (47%) of the 107 invited patients completed the questionnaire. Mean age was 25.0 years (SD 7.2)) and 22 (44%) were male. Eighteen (36%) had a mild injury, 13 (26%) a moderate injury and 19 (38%) a severe injury. Median time spent on moderate-vigorous physical activity was 518 minutes/week (IQR 236-1725) (males performing significantly more minutes on moderate-vigorous activity than women) and on sedentary activity 2728 minutes/week (IQR 1637-3994). Thirty-two (64%) participants met the D-HEPA. According to the CIS, 19 participants (38%) were severely fatigued. Both the CIS total score and the subscales motivation and physical activitywere associated with meeting the D-HEPA.The proportion of individuals with TBI meeting D-HEPA was similar to the general population, with the PA level being associated with self-reported fatigue.Physical activity programmes are continuously being developed to increase the percentage of individuals meeting public health recommendations for PA; when developing programmes for individuals with TBI extra consideration should be taken for the presence of fatigue. As in the general population, females with TBI are less active, PA programmes should probably consider gender differences in their development.

Source: Fatigue and its’ relationship to physical activity in adolescents and young adults with… – Abstract – Europe PMC

, , , , , , , ,

Leave a comment

[WEB SITE] Repetitive task training can help recovery after stroke

Repetitive task training can help recovery after stroke

Why was this study needed?

There are over 1.2 million stroke survivors in the UK, with around 152,000 cases reported every year. Stroke is the leading cause of long-term neurological disability, affecting balance, coordination and mobility. According to figures quoted by the Stroke Association, around 77% of stroke patients experience arm weakness and 72% experience leg weakness. It is important to understand which rehabilitation interventions might offer the best outcomes for patients to improve independence and quality of life. Repetitive task training is currently a component of stroke care so it is important to validate its effectiveness.

This Cochrane review is an update of an earlier review, last updated in 2007. Since then, 19 new trials have published results and the reporting standards have improved so these were added to the evidence base.

What did this study do?

This updated Cochrane systematic review included 32 randomised controlled trials and one quasi-randomised trial, involving 1,853 participants in all.

The trials were from various countries, including the UK, Australia, Canada and Korea.  Repetitive task training consisted of repeating a series of movements, with the aim of being able to perform a functional task. The training might involve the whole task, such as lifting a cup, or part of a task, such as grasping a cup. Most therapy interventions under evaluation lasted two to four weeks for between 10 to 21 hours.

Due to poor reporting in many of the original trials, it is difficult to assess the risk of bias. In addition, a wide range of interventions were used in the comparison groups. These factors mean researchers had a low to moderate degree of confidence in the main results.

What did it find?

  • For arms, repetitive task training had a small impact on improving function (standardised mean difference [SMD] 0.25, 95% confidence interval [CI] 0.01 to 0.49) – 11 studies, 749 participants.
  • For legs, repetitive task training provided small improvements in metres walked over six minutes (mean difference 34.8m, 95% CI 18.19m to 51.41m); walking ability (SMD 0.35, 95% CI 0.04 to 0.66); leg function (SMD 0.29, 95% CI 0.10 to 0.48); standing up from sitting (SMD 0.35, 95% CI 0.13 to 0.56) and standing balance (SMD 0.24, 95% CI 0.07 to 0.42).
  • There were no differences in functional ability after treatment according to the number of hours of training, the time from stroke to training or in the type of training delivered.
  • Repetitive task training was effective in the first six months, but no difference between groups was seen after six months.
  • Few trials reported on falls and other adverse effects making it difficult to assess the risks.

What does current guidance say on this issue?

Guidance from Royal College of Physicians in 2016 and NICE in 2013 recommends people are offered repetitive task training to improve arm and leg weakness, using activities such as reaching, grasping, sit to stand transfers and walking. The guidance recommends physiotherapists support people with movement difficulties and that rehabilitation continues until the person is able to maintain or improve functionality on their own or with the help of family or support staff.

What are the implications?

Given the range of participants included in these trials, repetitive task training could be appropriate for most people with weakness following a stroke. Clinicians and healthcare providers currently deliver repetitive task training as part of routine rehabilitation and through one-to-one or group training sessions.

There is insufficient information to draw conclusions on the optimal duration of sessions and the impact of current practices on therapist resource. The review suggests training is well received though it may be worthwhile to work with local patient groups to better understand their needs and preferences. Mechanisms to ensure adverse effects are reported and monitored are important.

An overview of NIHR funded research on stroke was published in March 2017, including aspects of recovery and rehabilitation after stroke. This can be downloaded free here.

Citation and Funding

French B, Thomas LH, Coupe J, et al. Repetitive task training for improving functional ability after stroke. Cochrane Database Syst Rev. 2016; (11):CD006073.

This project was funded by the National Institute for Health Research Cochrane Review Incentive Scheme and the Department of Health Research and Development Health Technology Assessment Programme.

Bibliography

French B, Leathley M, Sutton C, et al. systematic review of repetitive functional task practice with modelling of resource use, costs and effectiveness. Health Technol Assess. 2008;12(30).

NICE. Stroke rehabilitation in adults. CG162. London: National Institute for Health and Care Excellence; 2013.

RCP. National clinical guidelines for stroke. London; Royal College of Physicians, Intercollegiate Stroke Working Party; 2016.

Stroke Association. State of the Nation. Stroke statistics 2016. London: Stroke Association; 2015.

Source: NIHR DC | Signal – Repetitive task training can help recovery after stroke

, ,

Leave a comment

[VIDEO] Difference Between EMS Electrical Muscle Stimulation and TENS – YouTube

TENS vs EMS: the main difference between the two: TENS stimulates the nerves – the rationale being that the simulation keeps pain signals from reaching the brain. EMS causes the muscles to contract – by mimicking the action potential that comes from the central nervous system.Muscle Stimulation EMS stands for electronic muscle stimulation. These units are designed to provide relief by stimulating the muscles …Transcutaneous Electrical Nerve Stimulators (TENS) use electrotherapy to stimulate the nerves and active therapeutic healing. Electronic Muscle Stimulators (EMS), on the other hand, sends electric impulses that cause muscle contraction.EMS, or Electrical Muscle Stimulation, is the use of electrical pulses to generate a muscle contraction. EMS is typically used to enhance muscle …Neuromuscular Electrical Stimulation for Skeletal Muscle Function … nerve stimulation (TENS), and functional electrical stimulation (FES). ….. withdrawal of ES are present across different types of applications, such as …EMS (Electrical Muscle Stimulation) vs TENS. EMS or Electrical Muscle Stimulation, which is also referred to as neuromuscular electrical …The biggest difference between TENS and EMS is that TENS is designed to stimulate … The electrical muscle stimulation of an EMS device induces muscle …A TENS unit stimulates the nerve endings while the EMS unit stimulates the muscles. Amazingly enough, electrical stimulation of the nerves dates back to ancient Rome … pain reduction begins to last longer and the time between sessions lengthens. … The EMS units are specifically used to prevent atrophied muscles or for …Whether looking for a tool to boost your fitness and strength or recover from an injury quickly, electric muscle stimulation (EMS or NMES) can …

, , , , , , ,

Leave a comment

[Abstract] Hand strengthening exercises in chronic stroke patients: Dose-response evaluation using electromyography

Abstract

Study Design

Cross-sectional.

Purpose of the Study

This study evaluates finger flexion and extension strengthening exercises using elastic resistance in chronic stroke patients.

Methods

Eighteen stroke patients (mean age: 56.8 ± 7.6 years) with hemiparesis performed 3 consecutive repetitions of finger flexion and extension, using 3 different elastic resistance levels (easy, moderate, and hard). Surface electromyography was recorded from the flexor digitorum superficialis (FDS) and extensor digitorum (ED) muscles and normalized to the maximal electromyography of the non-paretic arm.

Results

Maximal grip strength was 39.2 (standard deviation: 12.5) and 7.8 kg (standard deviation: 9.4) in the nonparetic and paretic hand, respectively. For the paretic hand, muscle activity was higher during finger flexion exercise than during finger extension exercise for both ED (30% [95% confidence interval {CI}: 19-40] vs 15% [95% CI: 5-25] and FDS (37% [95% CI: 27-48] vs 24% [95% CI: 13-35]). For the musculature of both the FDS and ED, no dose-response association was observed for resistance and muscle activity during the flexion exercise (P > .05).

Conclusion

The finger flexion exercise showed higher muscle activity in both the flexor and extensor musculature of the forearm than the finger extension exercise. Furthermore, greater resistance did not result in higher muscle activity during the finger flexion exercise. The present results suggest that the finger flexion exercise should be the preferred strengthening exercise to achieve high levels of muscle activity in both flexor and extensor forearm muscles in chronic stroke patients. The finger extension exercise may be performed with emphasis on improving neuromuscular control.

Level of Evidence

4b.

Source: Hand strengthening exercises in chronic stroke patients: Dose-response evaluation using electromyography – Journal of Hand Therapy

, , , , , , , , , ,

Leave a comment

[ARTICLE] Effects of neurofeedback on the short-term memory and continuous attention of patients with moderate traumatic brain injury: A preliminary randomized controlled clinical trial – Full Text

Abstract

Purpose

There are some studies which showed neurofeedback therapy (NFT) can be effective in clients with traumatic brain injury (TBI) history. However, randomized controlled clinical trials are still needed for evaluation of this treatment as a standard option. This preliminary study was aimed to evaluate the effect of NFT on continuous attention (CA) and short-term memory (STM) of clients with moderate TBI using a randomized controlled clinical trial (RCT).

Methods

In this preliminary RCT, seventeen eligible patients with moderate TBI were randomly allocated in two intervention and control groups. All the patients were evaluated for CA and STM using the visual continuous attention test and Wechsler memory scale-4th edition (WMS-IV) test, respectively, both at the time of inclusion to the project and four weeks later. The intervention group participated in 20 sessions of NFT through the first four weeks. Conversely, the control group participated in the same NF sessions from the fifth week to eighth week of the project.

Results

Eight subjects in the intervention group and five subjects in the control group completed the study. The mean and standard deviation of participants’ age were (26.75±15.16) years and (27.60±8.17) years in experiment and control groups, respectively. All of the subjects were male. No significant improvement was observed in any variables of the visual continuous attention test and WMS-IV test between two groups (p≥0.05).

Conclusion

Based on our literature review, it seems that our study is the only study performed on the effect of NFT on TBI patients with control group. NFT has no effect on CA and STM in patients with moderate TBI. More RCTs with large sample sizes, more sessions of treatment, longer time of follow-up and different protocols are recommended.


Introduction

Traumatic brain injury (TBI) means an injury to the brain that is caused by an external physical force. It is well known that TBI is an important cause of mortality and morbidity and it is reported that each year about 1.7 million people sustain a TBI in USA. Some of them die (about 50,000) and some other experience long-term disability (80,000 to 90,000).12 ;  3 The severity of TBI can be categorized based on the Glasgow comma scale (GCS) at the time of injury as follows: mild (13-15), moderate (9-12) and severe (<9).4 TBI usually affect the brain function such as cognitive status, executive function, memory, data processing, language skills and attention.5 It has heterogeneous aspects and based on the injury location and type. It can have different presentations. Hence it is considered as a difficult one to treat.6

The brain plasticity could help it in rehabilitation phase to restore its normal function after any trauma or disease. But the amount of this ability is poorly understood. Some studies approved that neurofeedback therapy (NFT) can promote neuroplasticity.7 In the method of neurofeedback (NF), as a non-pharmacological intervention, the feedback to brain waves which are representative of subconscious neural activity can be observed by the client and then he/she will be able to control and change them.8 ;  9 There are some evidences that show NFT can be useful in some other diseases like Obsessive-compulsive disorder,10 attention-deficit/hyperactivity disorder11 and also refractory epilepsy.12 There are also some published studies about the effect of NFT on patients with TBI. Surmeli in 2007 investigated the effect of NFT on 24 patients with mild TBI and reported that NFT can result in significant improvement in test of variables of attention, beck depression inventory and minnesota multiphasic personality inventory.13 In a study in 2014, with evaluation of two patients with moderate head injury and without control group, it is reported that electroencephalogram biofeedback can lead to increase the cognitive scores and improve the concussion symptoms and finally concluded that NFT can be effective on the changes in the structural and functional connectivity among patients with moderate TBI.14

Although these published papers reported a positive effect of NFT on the TBI patients, we have not enough data about the standard treatment protocol with NF, and literature still needs more original studies like randomized controlled clinical trial to suggest NF as a treatment option among patients with TBI regarding the two following functions of cognitive status: short-term memory (STM) and continuous attention (CA).6

In this preliminary study, we tried to evaluate the effect of NFT on CA and STM of patients with moderate TBI using a randomized controlled clinical trial. […]

Continue —> Effects of neurofeedback on the short-term memory and continuous attention of patients with moderate traumatic brain injury: A preliminary randomized controlled clinical trial

, , , , , , ,

Leave a comment

[WEB SITE] Neuroprosthetics: Recovering from injury using the power of your mind

Neuroprosthetics, also known as brain-computer interfaces, are devices that help people with motor or sensory disabilities to regain control of their senses and movements by creating a connection between the brain and a computer. In other words, this technology enables people to move, hear, see, and touch using the power of thought alone. How do neuroprosthetics work? We take a look at five major breakthroughs in this field to see how far we have come – and how much farther we can go – using just the power of our minds.
woman with electrodes attached to skull]

Using electrodes, a computer, and the power of thought, neuroprosthetic devices can help patients with motor or sensory difficulties to move, feel, hear, and see.

Every year, hundreds of thousands of people worldwide lose control of their limbs as a result of an injury to their spinal cord. In the United States, up to 347,000 people are living with spinal cord injury (SCI), and almost half of these people cannot move from the neck down.

For these people, neuroprosthetic devices can offer some much-needed hope.

Brain-computer interfaces (BCI) usually involve electrodes – placed on the human skull, on the brain’s surface, or in the brain’s tissue – that monitor and measure the brain activity that occurs when the brain “thinks” a thought. The pattern of this brain activity is then “translated” into a code, or algorithm, which is “fed” into a computer. The computer, in turn, transforms the code into commands that produce movement.

Neuroprosthetics are not just useful for people who cannot move their arms and legs; they also help those with sensory disabilities. The World Health Organization (WHO) estimate that approximately 360 million people across the globe have a disabling form of hearing loss, while another 39 million people are blind.

For some of these people, neuroprosthetics such as cochlear implants and bionic eyes have given them back their senses and, in some cases, they have enabled them to hear or see for the very first time.

Here, we review five of the most significant developments in neuroprosthetic technology, looking at how they work, why they are helpful, and how some of them will develop in the future.

Ear implant

Probably the “oldest” neuroprosthetic device out there, cochlear implants (or ear implants) have been around for a few decades and are the epitome of successful neuroprosthetics.

The U.S. Food and Drug Administration (FDA) approved cochlear implants as early as 1980, and by 2012, almost 60,000 U.S. individuals had had the implant. Worldwide, more than 320,000 people have had the device implanted.

A cochlear implant works by bypassing the damaged parts of the ear and stimulating the auditory nerve with signals obtained using electrodes. The signals relayed through the auditory nerve to the brain are perceived as sounds, although hearing through an ear implant is quite different from regular hearing.

Although imperfect, cochlear implants allow users to distinguish speech in person or over the phone, with the media abound with emotional accounts of people who were able to hear themselves for the first time using this sensory neuroprosthetic device.

Here, you can watch a video of a 29-year-old woman who hears herself for the first time using a cochlear implant:

Eye implant

The first artificial retina – called the Argus II – is made entirely from electrodes implanted in the eye and was approved by the FDA in February 2013. In much the same way as the cochlear implant, this neuroprosthetic bypasses the damaged part of the retina and transmits signals, captured by an attached camera, to the brain.

This is done by transforming the images into light and dark pixels that get turned into electrical signals. The electrical signals are then sent to the electrodes, which, in turn, send the signal to the brain’s optic nerve.

While Argus II does not restore vision completely, it does enable patients with retinitis pigmentosa – a condition that damages the eye’s photoreceptors – to distinguish contours and shapes, which, many patients report, makes a significant difference in their lives.

Retinitis pigmentosa is a neurodegenerative disease that affects around 100,000 people in the U.S. Since its approval, more than 200 patients with retinitis pigmentosa have had the Argus II implant, and the company that designed it is currently working to make color detection possible as well as improve the resolution of the device.

Neuroprosthetics for people with SCI

Almost 350,000 people in the U.S. are estimated to live with SCI, and 45 percent of those who had an SCI since 2010 are considered tetraplegic – that is, paralyzed from the neck down.

At Medical News Today, we recently reported on a groundbreaking one-patient experiment that enabled a man with quadriplegia to move his arms using the sheer power of his thoughts.

Bill Kochevar had electrodes surgically fitted into his brain. After training the BCI to “learn” the brain activity that matched the movements he thought about, this activity was turned into electrical pulses that were then transmitted back to the electrodes in his brain.

In much the same way that the cochlear and visual implants bypass the damaged area, so too does this BCI area avoid the “short circuit” between the brain and the patient’s muscles created by SCI.

With the help of this neuroprosthetic, the patient was able to successfully drink and feed himself. “It was amazing,” Kochevar says, “because I thought about moving my arm and it did.” Kochevar was the first patient in the world to test the neuroprosthetic device, which is currently only available for research purposes.

You can learn more about this neuroprosthetic from the video below:

However, this is not where SCI neuroprosthetics stop. The Courtine Lab – which is led by neuroscientist Gregoire Courtine in Lausanne, Switzerland – is tirelessly working to help injured people to regain control of their legs. Their research efforts with rats have enabled paralyzed rodents to walk, achieved by using electrical signals and making them stimulate nerves in the severed spinal cord.

“We believe that this technology could one day significantly improve the quality of life of people confronted with neurological disorders,” says Silvestro Micera, co-author of the experiment and neuroengineer at Courtine Labs.

Recently, Prof. Courtine has also led an international team of researchers to successfully create voluntary leg movement in rhesus monkeys. This was the first time that a neuroprosthetic was used to enable walking in nonhuman primates.

However, “it may take several years before all the components of this intervention can be tested in people,” Prof. Courtine says.

An arm that feels

Silvestro Micera has also led other projects on neuroprosthetics, among which is the arm that “feels.” In 2014, MNT reportedon the first artificial hand that was enhanced with sensors.

Researchers measured the tension in the tendons of the artificial hand that control grasping movements and turned it into electric current. In turn, using an algorithm, this was translated into impulses that were then sent to the nerves in the arm, producing a sense of touch.

Since then, the prosthetic arm that “feels” has been improved even more. Researchers from the University of Pittsburgh and the University of Pittsburgh Medical Center, both in Pennsylvania, tested the BCI on a single patient with quadriplegia: Nathan Copeland.

The scientists implanted a sheath of microelectrodes below the surface of Copeland’s brain – namely, in his primary somatosensory cortex – and connected them to a prosthetic arm that was fitted with sensors. This enabled the patient to feel sensations of touch, which felt, to him, as though they belonged to his own paralyzed hand.

While blindfolded, Copeland was able to identify which finger on his prosthetic arm was being touched. The sensations he perceived varied in intensity and were felt as differing in pressure. 

Neuroprosthetics for neurons?

We have seen that brain-controlled prosthetics can restore patients’ sense of touch, hearing, sight, and movement, but could we build prosthetics for the brain itself?

Researchers from the Australian National University (ANU) in Canberra managed to artificially grow brain cells and create functional brain circuits, paving the way for neuroprosthetics for the brain.

By applying nanowire geometry to a semiconductor wafer, Dr. Vini Gautam, of ANU’s Research School of Engineering, and colleagues came up with a scaffolding that allows brain cells to grow and connect synaptically.

Project group leader Dr. Vincent Daria, from the John Curtin School of Medical Research in Australia, explains the success of their research:

We were able to make predictive connections between the neurons and demonstrated them to be functional with neurons firing synchronously. This work could open up a new research model that builds up a stronger connection between materials nanotechnology with neuroscience.”

Neuroprosthetics for the brain might one day help patients who have experienced a stroke or who live with neurodegenerative diseases to recover neurologically.

Every year in the U.S., almost 800,000 people have had a stroke, and more than 130,000 people die from it. Neurodegenerative diseases are also widespread, with 5 million U.S. adults estimated to live with Alzheimer’s disease, 1 million to have Parkinson’s, and 400,000 to experience multiple sclerosis.

Learn about Facebook’s newest endeavour: the development of BCIs.

Source: Neuroprosthetics: Recovering from injury using the power of your mind – Medical News Today

, , , , , , ,

Leave a comment

[VIDEO] The Effects of Brain Injury on Memory – YouTube

How does brain injury affect memory? Learn about memory impairment following brain injury in this video featuring NeuroRestorative’s Tori Harding. Following a brain injury, the deeply embedded and long-term memories usually remain intact while short-term memory may significantly be affected. Learn about the three memory system areas and strategies that can help a survivor improve their memory.

, , ,

Leave a comment

[WEB SITE] Spasticity, Motor Recovery, and Neural Plasticity after Stroke – Full Text

Spasticity and weakness (spastic paresis) are the primary motor impairments after stroke and impose significant challenges for treatment and patient care. Spasticity emerges and disappears in the course of complete motor recovery. Spasticity and motor recovery are both related to neural plasticity after stroke. However, the relation between the two remains poorly understood among clinicians and researchers. Recovery of strength and motor function is mainly attributed to cortical plastic reorganization in the early recovery phase, while reticulospinal (RS) hyperexcitability as a result of maladaptive plasticity, is the most plausible mechanism for post-stroke spasticity. It is important to differentiate and understand that motor recovery and spasticity have different underlying mechanisms. Facilitation and modulation of neural plasticity through rehabilitative strategies, such as early interventions with repetitive goal-oriented intensive therapy, appropriate non-invasive brain stimulation, and pharmacological agents, are the key to promote motor recovery. Individualized rehabilitation protocols could be developed to utilize or avoid the maladaptive plasticity, such as RS hyperexcitability, in the course of motor recovery. Aggressive and appropriate spasticity management with botulinum toxin therapy is an example of how to create a transient plastic state of the neuromotor system that allows motor re-learning and recovery in chronic stages.

Introduction

According to the CDC, approximately 800,000 people have a stroke every year in the United States. The continued care of seven million stroke survivors costs the nation approximately $38.6 billion annually. Spasticity and weakness (i.e., spastic paresis) are the primary motor impairments and impose significant challenges for patient care. Weakness is the primary contributor to impairment in chronic stroke (1). Spasticity is present in about 20–40% stroke survivors (2). Spasticity not only has downstream effects on the patient’s quality of life but also lays substantial burdens on the caregivers and society (2).

Clinically, poststroke spasticity is easily recognized as a phenomenon of velocity-dependent increase in tonic stretch reflexes (“muscle tone”) with exaggerated tendon jerks, resulting from hyperexcitability of the stretch reflex (3). Though underlying mechanisms of spasticity remain poorly understood, it is well accepted that there is hyperexcitability of the stretch reflex in spasticity (47). Accumulated evidence from animal (8) and human studies (918) supports supraspinal origins of stretch reflex hyperexcitability. In particular, reticulospinal (RS) hyperexcitability resulted from loss of balanced inhibitory, and excitatory descending RS projections after stroke is the most plausible mechanism for poststroke spasticity (19). On the other hand, animal studies have strongly supported the possible role of RS pathways in motor recovery (2036), while recent studies with stroke survivors have demonstrated that RS pathways may not always be beneficial (3738). The relation between spasticity and motor recovery and the role of plastic changes after stroke in this relation, particularly RS hyperexcitability, remain poorly understood among clinicians and researchers. Thus, management of spasticity and facilitation of motor recovery remain clinical challenges. This review is organized into the following sessions to understand this relation and its implication in clinical management.

• Poststroke spasticity and motor recovery are mediated by different mechanisms

• Motor recovery are mediated by cortical plastic reorganizations (spontaneous or via intervention)

• Reticulospinal hyperexcitability as a result of maladaptive plastic changes is the most plausible mechanism for spasticity

• Possible roles of RS hyperexcitability in motor recovery

• An example of spasticity reduction for facilitation of motor recovery […]

Continue —> Frontiers | Spasticity, Motor Recovery, and Neural Plasticity after Stroke | Neurology

, , , , , ,

Leave a comment

[ARTICLE] Using Brain Oscillations and Corticospinal Excitability to Understand and Predict Post-Stroke Motor Function – Full Text

What determines motor recovery in stroke is still unknown and finding markers that could predict and improve stroke recovery is a challenge. In this study, we aimed at understanding the neural mechanisms of motor function recovery after stroke using neurophysiological markers by means of cortical excitability (Transcranial Magnetic Stimulation – TMS) and brain oscillations (electroencephalography – EEG). In this cross-sectional study, fifty-five subjects with chronic stroke (62±14 yo, 17 women, 32±42 months post-stroke) were recruited in two sites. We analyzed TMS measures (i.e. motor threshold – MT – of the affected and unaffected sides) and EEG variables (i.e. power spectrum in different frequency bands and different brain regions of the affected and unaffected hemispheres) and their correlation with motor impairment as measured by Fugl-Meyer. Multiple univariate and multivariate linear regression analyses were performed to identify the predictors of good motor function. A significant interaction effect of MT in the affected hemisphere and power in beta bandwidth over the central region for both affected and unaffected hemispheres was found. We identified that motor function positively correlates with beta rhythm over the central region of the unaffected hemisphere, while it negatively correlates with beta rhythm in the affected hemisphere. Our results suggest that cortical activity in the affected and unaffected hemisphere measured by EEG provides new insights on the association between high frequency rhythms and motor impairment, highlighting the role of excess of beta in the affected central cortical region in poor motor function in stroke recovery.

Introduction

Stroke is a leading cause of morbidity, mortality, and disability worldwide (12). Among the sequels of stroke, motor impairment is one of the most relevant, since it conditions the quality of life of patients, it reduces their capability to perform their daily activities and it impairs their autonomy (3). Despite the advancements of the acute stroke therapy, patients require an intensive rehabilitation program that will partially determine the extent of their recovery (4). These rehabilitation programs aim at stimulating cortical plasticity to improve motor performance and functional recovery (5). However, what determines motor improvement is still unknown. Indeed, finding markers that could predict and enhance stroke recovery is still a challenge (6). Different types of biomarkers exist: diagnostic, prognostic, surrogate outcome, and predictive biomarkers (7). The identification of these biomarkers is critical in the management of stroke patients. In the field of stroke research, great attention has been put to biomarkers found in the serum, especially in acute care. However, research on biomarkers of stroke recovery is still limited, especially using neurophysiological tools.

A critical research area in stroke is to understand the neural mechanisms underlying motor recovery. In this context, neurophysiological techniques such as transcranial magnetic stimulation (TMS) and electroencephalography (EEG) are useful tools that could be used to identify potential biomarkers of stroke recovery. However, there is still limited data to draw further conclusions on neural reorganization in human trials using these techniques. A few studies have shown that, in acute and sub-acute stage, stroke patients present increased power in low frequency bands (i.e., delta and theta bandwidths) in both affected and unaffected sides, as well as increased delta/alpha ratio in the affected brain area; these patterns being also correlated to functional outcome (811). Recently, we have identified that, besides TMS-indexed motor threshold (MT), an increased excitability in the unaffected hemisphere, coupled with a decreased excitability in the affected hemisphere, was associated with poor motor function (12), as measured by Fugl-Meyer (FM) [assessing symptoms severity and motor recovery in post-stroke patients with hemiplegia—Fugl-Meyer et al. (13); Gladstone et al. (14)]. However, MT measurement is associated with a poor resolution as it indexes global corticospinal excitability. Therefore, combining this information with direct cortical measures such as cortical oscillations, as measured by EEG, can help us to understand further neural mechanisms of stroke recovery.

To date, there are very few studies looking into EEG and motor recovery. For that reason, we aimed, in the present study, to investigate the relationship between motor impairment, EEG, and TMS variables. To do so, we conducted a prospective multicenter study of patients who had suffered from a stroke, in which we measured functional outcome using FM and performed TMS and EEG recordings. Based on our preliminary work, we expected to identify changes in interhemispheric imbalances on EEG power, especially in frequency bands associated with learning, such as alpha and beta bandwidths. […]

Continue —> Frontiers | Using Brain Oscillations and Corticospinal Excitability to Understand and Predict Post-Stroke Motor Function | Neurology

Figure 1. Topoplots showing the topographic distribution of high-beta bandwidth (25 Hz) for every individual. Red areas represent higher high-beta activity, while blue areas represent lower high-beta activity. Central region (C3 or C4) in red stands for the affected side. For patients with poor motor function, a higher beta activity of the affected central region as compared to the affected side is observed in 16 out of 28 individuals. For patients with good motor function, a similar activity over central regions bilaterally, or higher activity over the unaffected central area can be identified in 21 out of 27 individuals. FM = Fugl-Meyer.

, , , , , , , ,

Leave a comment

[WEB SITE] Stroke rehabilitation device lets the patient do the shocking

 

When a person’s arm has become paralyzed due to a stroke, therapists often try to get it moving again using what’s known as functional electrical stimulation – this involves delivering electric shocks to the arm, causing its muscles to move. Studies have shown, however, that it works better when the patient is in charge of delivering those shocks themselves. A new device lets them do so, and it has met with promising results.

The system was developed by Intento, a company affiliated with Switzerland’s EPFL research institute. It consists of three parts: electrodes that the patient places on their arm, a controller that is operated by their “good” hand, and a tablet running custom software.

The therapist starts by selecting a desired arm movement on the tablet, and then loading it into the controller. A display on the tablet’s screen then shows the patient where the electrodes should be placed. Once those are attached, the patient sets about using the controller to deliver shocks to their arm muscles, resulting in the targeted movement – this could be something like pressing a button or picking up an object.

Ideally, once the action has been repeated enough times, the muscles will be “trained” and it will be possible for the patient to perform the movement without any external stimulation.

In a clinical trial performed at Lausanne University Hospital, 11 severely stroke-paralyzed patients – for whom other therapies hadn’t worked – used for the device for 1.5-hour daily sessions, over a course of 10 days. A claimed 70 percent of them subsequently “showed a significant improvement in their motor functions,” as opposed to just 30 percent who were undergoing conventional occupational therapy.

A larger clinical study is now being planned, after which the device will hopefully be commercialized. The research is described in a paper that was recently published in the journal Archives of Physical Medicine and Rehabilitation.

Source: EPFL

Source: Stroke rehabilitation device lets the patient do the shocking

 

, , , , , , ,

Leave a comment

%d bloggers like this: