So you grabbed your cup of coffee (or tea!), watched the TMT video and want to know more? Well click on the episode listing that you watched below and read more on the topic!
The Gross Motor Function Classification System is abbreviated as GMFCS for short. It is a five level classification system that is used to describe how children with cerebral palsy move and what equipment may be needed throughout the day. You may also see GMFCS-E&R which describes the extended and revised version.
The GMFCS-E&R was a recent addition to the GMFCS to encourage people to be aware of how the environment (such as the set up of the home, school or community) and personal factors (individual preferences) can affect mobility. It is important to remember that the GMFCS is used to represent usual performance that being what children would usually do as opposed to their best performance which can be difficult to sustain throughout the day.
For now, the GMFCS is used for children with cerebral palsy up to 18 years of age. It can't reliably be used for other neurological conditions as the classification on the levels is based on assessments on thousands of children with cerebral palsy where gross motor function was specifically assessed.
The gross motor function assessments allowed us to understand when skills tend to develop and when they tend to be maintained. After 18 years of age, we don't actually have information that tells us about how gross motor skills are maintained. However, as clinicians we do still use the GMFCS because it can best give us some idea of how the individual moves throughout their day.
Like I said in the video, the GMFCS only describes gross motor function - it doesn't describe how children communicate, socialise or think. Therefore it is important to use this system in the right context.
As an example, I have had discussions with people before about children with GMFCS level 2 where it was thought that because they were classified as "2", they wouldn't need any support at school. Indeed, a classification system of 2 would imply that the individual can walk but high gross motor skills like running and jumping may be more challenging so some support to modify school sports may be necessary. However, this classification system tells me nothing about how the child uses their hands - do they have enough strength and dexterity to participate in all the classroom skills? You can see here that the GMFCS level isn't particularly helpful to understand hand skills!
Another example are children with a GMFCS level of 4 or 5. Again, these numbers tell me that the individual uses a manual or electric wheelchair throughout their day. These numbers don't tell me anything about their ability to communicate or learn. I know many children and young people who have a GMFCS level of 4 or 5 that I have great conversations with and go to mainstream school.
So the bottom line here is to remember that it just describes one part of how a person functions in their day! If you were to catch me on one of my research days, I would sit in my chair - in front of the computer and pretty much not move. I would be horrified if you judged me based on just that day because my ability to think and talk are not related to the fact that I was sitting in my chair all day.
Next week, I'll talk more about how we use the GMFCS to guide what we do in therapy.
So if you'd like to know more about the GMFCS, please go to the following website. It is the original source! It has some great videos and downloads for parents, GMFCS levels described in different languages - its great!
Spasticity can often be described as having stiff muscles that make movement more restrictive for an individual. Spasticity is the direct result of an injury to specific parts of neural pathways in the brain and spinal cord. This injury alters the messages that are sent to the muscles and the result is stiffer muscles.
Spasticity is observed when a muscle is stretched quickly - the quicker the stretch, the stiffer the muscle appears. When you consider that a lot our natural movement requires muscles to stretch, you can understand that in an individual with spasticity - a lot of daily tasks can be affected. This includes fine motor skills, dressing, eating, walking, running and even speaking.
Spasticity is the most common type of cerebral palsy. According to the Australian Cerebral Palsy Register (2016), spasticity occurs in 85.8% of children with cerebral palsy. Of the children with spasticity, 39.1% present with spasticity on one side of their body (hemiplegia), 36.1% have spasticity predominantly in both legs (diplegia), 22.6% have spasticity in both arms and legs (quadriplegia) and 2.2% have spasticity in both legs and one arm (triplegia).
Assessing spasticity is important as it helps clinicians to understand the impact it has on individuals as well as to understand the effect of treatments that directly aim to reduce spasticity (such as botulinum toxin type A or otherwise known as Botox®). When assessing, it is important to consider that spasticity can appear heightened with emotions - with fear, anxiety and excitement.
Spasticity is just one component that contributes to how an individual with cerebral palsy or other neurological conditions and injuries move. Treating or managing spasticity often calls for a team approach involving Rehabilitation doctors, physiotherapists, occupational therapists and speech pathologists.
For more information on spasticity, head to the link below!
Keeping active is important for everyone. The National Guidelines for Physical Activity recommends vigorous activity for at least 3 days a week as well as to break up long periods of sitting as often as possible.
These guidelines promote cardio-metabolic health not just for now but as children get older. Adhering to these guidelines can be very challenging for children with neurological conditions and injuries because equipment and physical assistance is often needed throughout the day.
Walking frames become really important because they provide a safe means of enabling and facilitating walking in children with neurological conditions and injuries. In addition to providing a means to be physically active, it facilitates more independence which in turn enables greater participation with family and peers.
There are a lot of walking frames out there though! There are so many styles, features and qualities of a walking frame and they all have their advantages and drawbacks. In my experience, I have come to realize that there is no such thing as the perfect walking frame for every situation. In the ideal world where funding is not an issue, I’m a big believer in a walking frame that is used everyday and a walking frame that is used for therapy.
An everyday walker is one that provides all the necessary support so the child and young person can be safely independent to move around in their own environment with as minimal physical assistance as possible. A therapy walker is one where the child and young person is more challenged. This means that posture, strength and endurance is challenged as a means to enhance and improve skills as part of a therapy program.
In saying this, there really are 2 main walking frame styles - an anterior (where the support is in front of the person) and posterior style walker (where the main support is behind the person). The perfect match up for an everyday and therapy walker is usually a combination of these styles and this is why it is so important to trial a walker, have open conversations about what works and what doesn’t.
So the question becomes - what is the goal of the walker? Is it one that can be used everyday to promote participation and can we also use the walker in therapy to challenge and develop skills?
I’m going to share my decision making table with you that provides a guide on what kind of walkers can be used for children of different GMFCS levels. It is just a guide but is a great place to start when having conversations about walking frames.
National Guidelines for Physical Activity recommendations.
Learning a new skill is something that we can all relate to. You probably already know that to learn something new - you need to practice it so that it becomes second nature. For people with neurological conditions and injuries, it is even more important to be deliberate and intentional about how we teach new skills so that it can be incorporated as a skill in everyday life.
In therapy, we call this “motor learning”. There are 10 core principles on how to maximise motor learning so that it can facilitate more permanent changes in the brain. The process of facilitating these changes in the brain are referred to as neuroplasticity. Being intentional and being deliberate about motor learning is not just important for new skill attainment but also for maximising what you get out of therapy. Afterall, we need to be responsible and ethical with using limited funds that are entrusted to us by the public.
The first principle we discussed today was specificity - that is, being specific about the training that you do. I know it seems really obvious, but it does deserve time to stop and reflect to ensure we are being specific. We know when we learn, it is important to practice the task or activity. This may involve breaking it down to its components but at the core, the way we learn the activity is to ensure that the way we practice it is in context and how we would actually do it. This is why we call it Activity Based Therapy.
The term Activity Based Therapy represents a shift for the modern day therapist. We gave you some examples in the video, but let me share another one with you. For quite some time, researchers were looking to see if stretching was effective in improving walking for children with cerebral palsy. It is now quite definitive that stretching is indeed, not effective for improving walking but it doesn’t mean that stretching alone doesn’t have it’s benefits. If we want to improve walking, we need to be specific about structuring therapy to focus on walking. Simply stretching in isolation on a mat somewhere doesn’t improve how we walk.
It’s the same with walking - if the goal is for a child to be able to move more independently (by that, it means less adult hands on assistance) then using a walking frame that is set up to promote success and independence is crucial. Therefore practicing in a walking frame becomes really important.
Setting goals that are specific and focused on activity lay the foundation for developing a therapy program that is more likely to be effective and change pathways in the brain.
As you prepare to work with your therapist in setting goals, perhaps use the SMART goal framework:
Specific: What is the specific activity that we are focussing on? Think of the actual activity as opposed to “increase strength” - an activity would be a task such as increase trunk strength so that my child can sit independently on the floor.
Measureable: How will you know it has been achieved? Is it the completion of an activity, the number of repetitions? The amount of support that needs to be provided?
Achievable: We all have big goals and smaller goals that work incrementally to reach the big goals. So have a think about breaking down the components in therapy that all work toward the bigger goal.
Realistic: This is where we combine the knowledge you have about your child (their personality and their strengths) alongside your therapist who will have knowledge about the condition or injury. Therapists who are grounded in research and knowledge in an area will know what increments to expect, what is safe to pursue and what is recommended by experts in the area. Being realistic is all about combining family knowledge with therapist knowledge - a true partnership.
Timely: When do we expect that this will be achieved? What timeline is going to drive everyone toward this goal? Again, this might be a larger goal that is broken into components.
So a SMART goal might be:
For Jane to be able to sit cross legged on the carpet on the floor with her sisters so that she can watch an entire episode of The Wiggles and use her hands to do the actions. We aim for this to be achieved in 3 months.
Remember, this is just one component but a really important one.
Fun! I love that this is actually one of the core components of motor learning. It is actually all about being engaged in a task so that it is meaningful. What this means is that the environment on a cellular level is ideal for learning - this is often referred to in science articles as “experience-dependent plasticity”.
Essentially, for there to be plasticity (for changes in the brain) - experiences are important and these need to be the right experiences. Not only does a task or skill need to be practiced within a specific context and in a specific way, but the experience of it needs to be ideal as well.
We know that emotions can consolidate the strength of the experience, so being in a place where it is encouraging and fun is a great place to start. I’m sure you can relate to this as well! Many people have taken music lessons at some point in their life. You often hear people who didn’t continue with taking music lessons because they found their teacher too strict, or the method of teaching didn’t really suit the learner. Under those conditions, it really does take a lot to keep going, taking lessons and practicing enough to be good at the instrument - even if you are a really motivated and hardworking person!
On the other side, you also hear of people who had great experiences - an encouraging teacher making lessons fun and engaging. This, coupled with a desire to want to learn makes it more likely that you practice and get the repetitions in to be proficient enough to enjoy the instrument.
So fun is important - there is good science to support this. We should never stop having fun, but if you are a child - fun is essential. The link here provides some great tools that help to ensure that fun or “what floats your boat” is incorporated into therapy.
Today in our series on neuroplasticity and motor learning we are speaking about “use it or lose it and use it to improve it”. We know that if we don’t practice a particular skill or use a part of our body then over an extended period of time the neural circuits associated with that skill or movement begin to degrade.
This is seen often in those with neurological conditions where one side is more affected than the other and active movement may be more challenging due to muscle weakness, spasticity and reduced range of motion. These factors may inhibit the use of the more involved hand in daily life activities which impacts acquisition and development of motor skills, this is often referred to as learned nonuse.
There is a “map” of your entire body across the part of your brain called the cortex. The sizes of different body parts on the map depend on how much they are used – for example the hands, eyes, lips and tongue are all much bigger on the map because these parts of the body are used most for sensation and function.
This map is constantly changing in relation to how you use your body. When a part of the body is used less, such as an arm and hand affected by a stroke or brain injury, its representation on the brain will shrink. If that person has learned nonuse of the arm, they will continue not to use it and it won’t regain its true representation on their brain.
Intensive training of the upper limb reorganises brain activity and increases the representation of the upper limb in the brain, this is called cortical reorganisation. Two examples of evidence based interventions that target cortical reorganisation include constraint induced movement therapy (CIMT) and bimanual training.
Constraint induced movement therapy (CIMT)
CIMT involves discouraging the use of the stronger arm while encouraging the person to use their weaker arm in situations where they may have previously used their stronger arm entirely. The aim is intensive practice of skills such as reaching, grasping, releasing and manipulating objects only using the more affected side.
Bimanual training is intensive and repetitive practice of specific activities that require the use of two hands together. Most everyday activities are easier to complete with two hands together - for example, catching a ball, putting on a shirt, using a knife and fork and even playing a video game. Individuals with neurological conditions often have difficulty performing activities that rely on the coordinated use of both hands, because of movement difficulties in the more affected hand. The key difference to CIMT is that in bimanual training both hands are involved and working together in a coordinated way.
Both of these types of interventions utilise the principles of neuroplasticity and motor learning such as being intense, repetitive and meaningful to the individual and most importantly are delivered in a fun and engaging way to maximise therapy.
Intensive therapy is such a great way to improve skills to facilitate more permanent changes in the brain. It is so important to remember that intensity is one of the principles for motor learning in children with neurologically based conditions or injuries (such as Cerebral Palsy). All of the other factors that include specificity, repetition through engagement and fun, being goal directed, finding opportunities to practice (use it or lose it) and training specific tasks (use it to improve it) are instrumental in enabling a more intensive schedule of sessions to be effective.
It is always great to consider “intensity” versus “density”. There are certainly some skills that require adequate practice. Therefore, repetition in contextually relevant environments (i.e. repeatedly practicing the task in places where you would normally need those skills) can provide the right “density” of practice. It helps the person to recognise their own ways of moving and performing the task in order for it to be successful. For this reason, embedding practice of tasks throughout the day enables greater opportunities to consolidate those skills so that it can become more automated.
However, it is also important to consider whether the dosage is too “dense”. There is a big difference between having say 16 sessions over 2 weeks versus 16 sessions over 4 weeks. Though the number of sessions is the same and I would say they are both very “intense” in nature there are some key differences and factors to consider.
Densely packing 16 sessions over 2 weeks doesn’t really give the body time to recover (which is important for skills that need physical capacity like strength and fitness) and it also doesn’t give the child a chance to practice those skills in their own daily contexts.
Exploring and finding opportunities to put new skills into practice does need time so if you can marry an “intensive” program under the guidance of experienced therapists with “intensive” practice in contextually relevant environments, you are more likely to achieve goals and be efficient and effective with limited funds.
The role of intensive therapy is to explore, find engaging ways to draw out the best in each person so that those new skills can be put into practice each and every day because we know that daily practice is more effective. Intensive therapies should be timed so that there are specific periods during the year where a new skill can be targeted. The role then of therapies and therapists outside of these intensive periods is to fine tune and help the new skills to be put into practice within the home, school and community.
The biggest take home here about intensive therapy is active participation. If the person learning the skill is actively involved and is actively moving within context of how the skill will be used, the new skills are highly likely to be retained.
This week there is a special follow up video to be released this Thursday (August 15, 2019) that will go into even further details about intensity, density, rest and recovery in all the various aspects of intensive therapy.
The National Disability Insurance Scheme supports and funds a range of services that aim to improve a person’s ability to participate, to be more independent as well as to improve a person’s health and well-being. The key factors are around a service being reasonable and necessary, represent value for money and are effective and beneficial to assist in the pursuit of goals and aspirations.
Research is a method that enables treatment effectiveness to be determined. However, not all research is the same. An important thing to remember is that not everything that is written down represents good science or the actual facts. Bias is the number one factor that needs to be considered and controlled. This is why research protocols or how a research study is conducted is so very important.
If you were to compare the before and after effects of a single group of people following therapy, we would call that a one group design. We are so familiar with this - its the before and after following a diet or exercise program. We see them all the time on social media! Essentially in research, what this means is that one group of people receive the same therapy and you would compare the before and after to say whether or not it worked.
This method is great at getting a bit of an idea of how the therapy might work and what it might mean for future research. The results of these forms of research studies need to be interpreted and implemented with caution though. This is because there can be bias that skews the results - this can be in favour of the treatment or it could also work against the treatment. When you only have one group of people experiencing the treatment therapy, you actually don’t know whether that group of people (or that sample as termed in research) had personal characteristics that made them respond more favourably, or not. So, you don’t actually have a lot of confidence in saying that those results will actually translate to a similar group of people outside of the study.
A randomised controlled trial is the most ideal form of research. Essentially, researchers are comparing two different conditions - a treatment and not receiving treatment. By randomly allocating them to different groups, you have no control over who goes into what group and you reduce the chance of bias. Even better is if you “blind” the assessors.
This just means that the people who are performing the assessments actually have no idea what group the participants are in. This again reduces bias to either group. If a study is done well, it means that you have greater confidence in knowing that the results can also translate to other people with a similar condition.
If you collect a bunch of studies that are randomised controlled trials, you can then look at all of the results and be very confident in knowing that something is effective or not! This is called a Systematic Review. This is what a research group led by Iona Novak from the Cerebral Palsy Alliance did in a paper they published in 2013. They graded a bunch of studies to see if they were good quality and then looked at all the results. This has been such an influential paper because for the first time, we were able to say what therapies children with cerebral palsy should do and what they shouldn’t do!
So what therapy should we do and what should be funded? This research paper gives a great outline and we will go into more detail about this in the coming weeks. But if you can’t wait, you can find the article here
So is it worth it? In this week’s Two Minute Tuesday, we talk specifically about what is above the line as an effective intervention for children with cerebral palsy and what is below the line. When it comes to the area of “improving motor activities” we are talking about skills that improve mobility, whether this relates to the use of hands or gross motor skills like sitting and standing.
There are two categories when we talk about what is above "the line".
There are the green light interventions that have a substantial body of evidence to support its effectiveness. As the “green light” suggests, it is all systems go! These interventions have evidence to support its use and really, should be funded because it represents value for money in addressing areas that are reasonable and necessary.
The yellow light interventions are split into two - some are above the line and some are below the line. The difference between the interventions that are above and below the line is that the ones above the line have a growing body of evidence to support its effectiveness. It just needs more studies to help to really prove it. These areas are the ones that are the focus for a lot of current researchers because it is a needed area of research. It may be that more randomised controlled trials are needed to give the current research more strength and therefore increase our confidence in knowing that the results from those studies can translate to the broader group of children with cerebral palsy. The interventions below the line mean that though there is some evidence out there, it is all pointing in the direction of being not effective. There is less confidence in knowing that these represent value for money.
The red light interventions are more obvious - these interventions have been proven to be ineffective and should not be used. It is also important to note that interventions that have not even made it to the list. This usually means that there have been no studies done on that intervention so there is no knowledge on whether or not it is effective.
It is important to note that this paper relates to children with cerebral palsy. It can’t necessarily be translated to other populations. However, given that the effective interventions are based on principles of motor learning - this is not diagnosis specific. Motor learning principles apply to everyone so there is a lot we can gleen from this!
Being an evidence based therapist means that we embrace new evidence and turn away from therapies that are proven to be not effective (or not even listed here). For families making decisions on what therapies to spend time and money on, I strongly encourage you to ask questions about whether the intervention is proven and how it relates to your child.
These are important questions and this is truly family centred practice - where therapist and family and child can work together to make informed decisions with what is often limited time and resources.
Take a moment to see the figures below that show the Green, Yellow and Red interventions. Also, for more information please see the link below.
So what does it actually mean to provide and receive therapies that are “above the line”?
It all essentially comes down to using the best available evidence. In the article I have been referring to (Novak et al 2013), there is a line that distinguishes between “worth it - probably do it” and “not worth it - probably don’t do it”. This paper was published over 5 years ago and since then there have been some updates so we are looking forward to seeing what the authors will publish in their next big review!
When selecting interventions that are still in the “yellow” category but still above the line, it is important that routine outcome measurements are used so that the effect of the intervention can be determined for each individual. This should also be coupled with being very goal directed as well as incorporating all of the principles we spoke about in the last series regarding motor learning.
In the case example I provided today, I mentioned a variety of interventions that will be implemented. It was important for me to only choose interventions that are above the line because at the end of the day, by doing so - I can be confident that in the limited time I get the privilege and opportunity to work with this particular young man, that we are doing everything we can to give him the best chance to learn new skills and increase his independence and participation. Choosing a suite of interventions also highlights the need for multidisciplinary teams.
Learning to use AAC is clearly led by a speech pathologist. However, the support of physiotherapy and occupational therapy can ensure that environmental modifications can occur and gross motor skills are at its best to optimise access to AAC.
There can be so many different terms relating to tone that can be thrown around when you attend a clinic. The terms spasticity, hypertonia, hypotonia, dystonia, dyskinetic movements are all words that describe the tone or how muscles feel when they are moved. It can become very confusing but it is important to be able to identify and distinguish one from the other because treatments can be quite different.
This is why a group of paediatricians, rehabilitation physicians, neurologists and therapists put together a “task force on childhood motor disorders” in order to come up with a consensus agreement on how to define differences in muscle tone. These papers have been very influential!
So the topic we covered today was the definition of dystonia. The taskforce defined it as “a movement disorder in which involuntary sustained or intermittent muscle contractions cause twisting and repetitive movements, abnormal postures or both”. Dystonia influences how someone voluntarily moves and can also influence how someone is able to hold their posture. It can therefore really affect how someone functions throughout their day - whether it be for maintaining head control, using their hands, sitting, standing or walking.
Dystonia can be described as being “focal” in that it can be specific to particular muscles that affect a joint. Dystonia can also be more generalised. With both of these presentations, they tend to be very stereotypical and look like “inserted postures” within movement. It can appear when the person is trying to complete a particular task and can be influenced by how the person feels (emotional state), how tired they are, touch or pain.
As a result, the muscle can feel very stiff and the stiffness may seem to fluctuate making movement more unpredictable. So for example, someone with dystonia may be able to suddenly extend their body so it appears that they can stand quite well. However, this increased tone or sustained posture may vary in length and can result in a sudden relaxation. For the person who was standing, the sudden relaxation may cause them to suddenly collapse. For this reason, if a walking frame is being used, it is important to have a safety mechanism (like a saddle seat) that enables the person to practice walking whilst having the confidence to continue to walk without suddenly collapsing. So in a way - a saddle seat can promote independence.
Alternatively, if someone has more localised dystonia such as in their calf muscle - a more specific treatment such as the use of functional electrical stimulation to lift the toes up whilst walking is favourable. This is particularly indicated following botulinum toxin type A (Botox ®) as we know that Botox ® is effective in treating dystonia.
So within dystonia itself are varied presentations and understanding this and working alongside the medical and allied health team is important to being able to treat and facilitate functional movement.
If you’d like to read the article, you can find the link below.
Hypotonia describes low tone in a person’s body. It is common to report hypotonia in a range of conditions that include cerebral palsy, congenital syndromes and global developmental delay. Children with hypotonia may often be described as having poor trunk or head control. At birth, a baby may be described as being more “floppy”.
Children with hypotonia will mainly have difficulties when they are in positions that make their body work against gravity. This includes being upright such as sitting or standing. There can be quite a range of the extent of hypotonia in someone, but it is more common to describe hypotonia as being generalised i.e. that it affects the entire body of the person. As such, the child may have the appearance of collapsing over and so require more hands on support or equipment in order to be upright for longer periods of time.
It is common to have hypotonia alongside high tone such as spasticity or dystonia. So whilst muscles in the arms and legs may appear stiff at times, the trunk or the body may have low tone and this will have an impact on how the child holds their head up. For this reason, hypotonia is often observed in children with cerebral palsy who are more dependent on equipment and physical assistance throughout their day.
There can be a variety of reasons that contribute to the presentation of hypotonia. It can be largely due to reduced signals from the brain to the muscles as well as muscles itself having more difficulty contracting. It is very likely that it is a combination of a variety of factors.
When there is hypotonia involved, medications are not usually helpful. Most medications “take away” something such as Botox which can “take away” spasticity for a short period of time. It is more difficult to “give more tone”.
So what can be done? The key factor here is to participate in Activity Based interventions. We'll get into that in more detail in the coming weeks ahead!
The combination of Neuromuscular Electrical Stimulation and a specific activity (we often call it a task specific activity) is referred to as Functional Electrical Stimulation (FES). In this instance, the sticky electrode pads are placed on the target muscles and are timed to flex or contract during a very specific movement. An example of this is using the electrical current to stimulate the muscles at the front of the leg to lift the toes up. If this movement is done with a person sitting on a chair, it is simply referred to as NMES.
However if the same thing is done but the electrical current is timed so that it lifts the toes up with each step whilst the person is walking, it is known as Functional Electrical Stimulation. This is important for the person because the muscles that are needed to lift the toes up when walking are weak and this can cause tripping or falling when walking. However, if the device is used to help the person do this, it can greatly improve how a person moves at home, school and community.
Muscle electrical stimulation is a therapy that is used to enable a person to flex a muscle. For people who need therapy for muscle strengthening, this method can be used because the muscle can be flexed without the person being able to do so on their own. This may be because the muscle is weak or paralyzed. Sticky pads are placed on the skin over the target muscle. This enables a controlled electrical current from a small device to safely make the muscle flex. The timing of the electrical current can be programmed on the device to help someone use a muscle when moving. A great example of this is flexing the muscles on the front of the leg to lift up the toes when walking.
The controlled electrical current applied through the sticky pads from the device tries to copy what happens when the brain tells a muscle to flex or contract. When our brain tells a muscle to contract, it sends an electrical current that travels through the nerves in our body. This sets off a series of chemical reactions at the place where the nerve meets the muscle. Muscle electrical stimulation does this as well but instead of the brain sending the electrical current through the body, a device is used to send the electrical current directly to the muscle.
Muscle electrical stimulation works when the nerve is properly connected to the muscle. This means that the signal is working well so all it needs is an electrical current to enable the muscle to flex or contract. Muscle electrical stimulation works because the person doesn’t need to be able to flex or contract it themselves, the device can do it for them. This can then teach the pattern and habit of how the person can learn to use the muscle themselves.
The Next Steps Project website is a great source of information on Electrical Stimulation along with having some dedicated F.E.S. equipment reviews as well!