Why is electrical stimulation used in rehabilitation?
Are you dealing with a neurological condition that requires rehabilitation? You may have heard about electrical stimulation, sometimes known as FES (Functional Electrical Stimulation) or electrotherapy, before. If so, you might be wondering why it is often used in rehabilitation and whether it is right for your specific situation.
In this article, we are going to explore the concept of electrical stimulation and what its use in physical therapy offers in particular for individuals recovering from neurological conditions. Read on to learn more about how electrical stimulation works and how it can help speed up recovery and improve function after an injury or neurological condition.
Understanding electrical stimulation
For those recovering from a spinal cord injury or stroke, or perhaps living with multiple sclerosis, Parkinson's disease, or other neurological conditions, electrical stimulation can be a game changer. But what exactly is electrical stimulation?
Let's start by pointing out that It's a low-risk and non-invasive method that delivers small electrical impulses to targeted areas of the body. This can, for example, trigger muscular contractions. By doing so, it can help individuals regain muscle strength lost through their illness or accident. Other forms of energy applied to the body can have effects too but electrical stimulation is particularly useful as stimulation systems can be designed to deliver precisely controlled patterns of electrical energy.
Electrical stimulation isn't just for muscle strengthening though. It can be used for many applications including relaxing tight muscle, improving circulation, helping wounds to heal and managing pain. And while electrical stimulation is not a cure-all solution, it's certainly one that's worth considering for those seeking to augment their rehabilitation efforts or manage their conditions.
Electrical stimulation can be a confusing topic as sometimes the terminology is not clear and people can use different words to describe the same techniques. We will mention some of these terms below.
There are some general-purpose electrical stimulators in which the character of the electricity can be adjusted and there are some stimulators that just have one dedicated application such as to remedy a dropped foot after a stroke. In fact, devices that use electrical stimulation, to help remedy a dropped foot after a stroke is a fairly common application.
All electrical stimulation devices are not the same and therefore it is important to seek out knowledgeable advice before choosing one for your situation.
Benefits of electrical stimulation therapy
Electrical stimulation has proven to be a safe and non-invasive method of treatment for a variety of medical conditions. This form of therapy involves applying carefully chosen patterns of electrical current to different parts of the body; typically by using surface electrodes applied to the skin over an affected body part.
The beneficial effects can be optimised to relieve different types of pain, relax tight muscles, strengthen weak muscles, heal wounds or even produce muscle contractions when nerves are damaged.
Commonly, 'sticky' electrodes may be placed over the belly of a muscle to stimulate the nerves and produce a muscle contraction. In some cases, specialised electrodes must be used depending on the level of energy being used.
Electrical stimulation can be especially beneficial when an individual has difficulty in consciously contracting a muscle for themselves as we will see shortly. The patterns of electricity are chosen to produce different effects and are generally quite low in intensity. Varying the pattern and intensity of the electricity can produce very different effects and ideally maximise function whilst minimising any possible discomfort for the user.
What's great about electrical stimulation as a therapy is that it is widely available and can be used for general purposes, such as reducing pain and inflammation, as well as for specific applications, such as treating disorders like Parkinson's disease or multiple sclerosis. Whether you're an athlete recovering from an injury, or simply seeking relief from chronic pain, electrical stimulation therapy is worth exploring as a potential treatment option.
Types of electrical stimulation used in rehabilitation.
There are many types of electrical stimulation and indeed terms to describe these various forms. We can think of electrical stimulation as an 'umbrella' term covering many approaches including the following which you may discover in the literature
NMES – neuromuscular electrical stimulation
EMG-NMES – electromyography-triggered neuromuscular electrical stimulation
EMS – electrical myostimulation
FES – functional electrical stimulation
TENS – transcutaneous electrical nerve stimulation
cNMES – cyclic neuromuscular electrical stimulation
IFT – interferential therapy
Russian stimulation
Diadynamic therapy
I could easily continue this list, but at present, there isn’t a universally agreed classification system that applies to all known modalities and avoids ambiguities.
For example, TENS is commonly thought of as sensory nerve stimulation used primarily for pain relief, but most other forms of stimulation are, strictly speaking, transcutaneous too because they involve the use of gelled surface electrodes from which the energy penetrates the body.
FES is perhaps the most relevant to describe applications where functional movement is the objective in rehabilitation.
Over the last fifty years our understanding has improved, and with it the technology to make FES one of the most powerful and flexible tools we have for rehabilitation. Despite its long pedigree, electrical stimulation is not well understood in its various forms or applied widely enough for therapeutic purposes.
Let's take a look at a form of electrical stimulation that is particularly valuable in neurorehabilitation - so-called FES Cycling.
FES Cycling or FES bike technology
FES Cycling with a RehaMove
FES Cycling synchronises the delivery of electrical stimulation with the movement of the pedals of a passive/active bike. This is a technology we have worked with since 2007 at Anatomical Concepts and we have many home-based users as well as NHS and private clinics using these systems.
Our version of an FES bike is currently called the RehaMove system. FES Cycling is a remarkable technology that can revolutionise the lives of those struggling with weak or paralysed muscles. The RehaMove system synchronises the delivery of electrical stimulation with the rotating pedals of a passive active bike, allowing a user to pedal using their own muscles thereby producing active exercise.
Whilst there is some value in using a passive/active bike to just move the legs through a range of motion, the benefits are more profound when this movement is turned into active exercise with the use of FES. An FES Cycling system combines a programmable stimulator with a passive active bike and allows the user to optimise the muscle contractions produced for therapeutic effect.
Over time the muscles can be strengthened with many health benefits. This technology is widely used by many of our clients with spinal cord injury. Research evidence has shown benefits for long-term cardiovascular fitness, peripheral circulation, muscle bulk and tissue quality, bone health and much more. Just like any form of exercise, FES Cycling is best carried out several times a week to produce health benefits.
In the case of an incomplete spinal cord injury or with stroke, MS or Parkinson's, an FES Cycling system user may gain function that is hard to get via other approaches.
Unfortunately, the price of these systems can mean they are beyond the reach of many people except those with insurance or a medico-legal claim. FES Cycling is valuable in stroke, MS and Parkinson's but we have fewer home-based clients with these conditions simply due to the cost of the products.
Augmenting exercise with electrical stimulation
The world of exercise and therapy has been revolutionized with the help of Sequence Mode software which is provided as part of our RehaMove FES Cycling system. This innovative technology is designed to augment user-selected exercise routines and make therapies more effective for individuals who may have experienced injuries or disabilities.
Some examples of Sequence Mode stimulation - wrist extension and shoulder stabilisation exercises
With this software, therapists can create personalised exercise plans for their clients that take into account their unique physical needs and limitations. Rather than relying on generic routines, which may not be effective for everyone, Sequence Mode software offers a specialized approach that ensures individuals are getting the most out of their workouts. Whether someone is looking to recover from an injury or strengthen their body, this technology is helping to make it all possible.
The software is called Sequence Mode because it allows quite complex sequences of muscle stimulation to be generated. These sequences may repeat for some time or be activated only in response to a key press. Common applications might be to assist a person with a spinal cord injury to carry out a 'sit to stand' manoeuvre. For this application, the quadriceps muscles of the thigh and the gluteal muscles can be activated once the therapist presses a button. Initially, the quadriceps are activated followed by the gluteals some fractions of time later. This could assist the user to achieve a standing posture and holding it for some time. Other applications might include helping a client to practice and improve walking after a stroke, or a programme to develop arm and hand movements required for an individual to feed themselves following a stroke. In this sense, Sequence Mode is a therapy tool that uses FES to achieve a functional goal and repetitively practice a movement.
Wound healing with electrical stimulation
Chronic wounds such as this sacral ulcer can be helped with electrical stimulation but this is a specialist area for a serious condition
Wound healing is an application of electrical stimulation that is less well-known and still lacks research to identify the best protocols of energy to use. There are various types of wounds too - some are a result of pressure on insensitive skin, there are diabetic ulcers, leg ulcers and similar that can be influenced by nerve injury and circulation challenges. We know that not all of these wounds will respond equally to electrical stimulation.
Wound healing is a fascinating natural process that allows the body to repair damaged tissue and regenerate new cells. There is some rationale for using electrical energy to heal a tissue wound as it has been long observed that there is an electrical potential difference between the skin and deeper tissues. A sort of 'skin battery'.
The body's ability to heal wounds is a complex interplay between different cells, tissues, and organs, all working together in perfect harmony. When the skin is broken, the body immediately responds by sending a rush of blood and oxygen to the site of injury. This activates the immune system, which kicks into gear to fight off any invading bacteria or viruses.
Over time, new tissue and skin cells start to grow, filling in the wound and allowing it to gradually heal. Although wound healing can take time and patience, the result is a stronger and healthier body that can overcome even the most challenging of obstacles.
Electrical stimulation can be a successful modality even for chronic wounds that are reluctant to heal but this is a specialist area and home users should only explore this method with competent guidance
Denervated muscle and peripheral nerve injuries
The RISE unit is optimised to provide electrical stimulation for denervated muscle
Muscle strengthening with FES, as with FES Cycling or Sequence Mode stimulation, relies on intact muscle architecture. However, some types of spinal cord injury low to the spinal cord affect what is called the lower motor neurons. The result of this is that the muscles served become denervated. Similarly, peripheral nerve injuries via cuts or trauma can result in denervation. When this is the case, the forms of electrical stimulation that rely on an intact nerve structure will not work.
Anatomical Concepts can supply technology that will work with denervated muscle by utilising a different type of electrical energy that works directly with muscle fibres. Such a stimulator can reverse the consequences of denervation that cause loss of muscle bulk and tissue quality. If left untreated denervated muscle can lead to poor appearance and increase the risk to peripheral circulation and lead the injured person to be at greater risk of pressure and other wounds that can be slow to heal.
Risks of using electrical stimulation
As we described above, electrical stimulation is a remarkably safe technology but it should be understood that there are always contraindications that should rule out it's use. For many medical devices, there are likely to be absolute and relative contraindications that apply in particular circumstances.
Common contraindications would include not stimulating when a person has epilepsy, not stimulating directly over open wounds, over metal implants, in cases of pregnancy or across the chest. It is best to explore the contraindications that apply in a particular case with a knowledgeable professional. The user manual of a medical device for electrical stimulation will also identify possible contraindications and this should be consulted in all cases.
Even when no contraindications apply, attention should be given to the type, size and quality of electrodes used in each case. Failure to use the right type of electrode can result in skin irritation or even electrical burns although these should be a very rare occurrence. Most electrodes will cause few problems but rarely an individual will be prone to skin rashes and in these cases hypoallergenic electrodes can be used.
When to seek professional help with electrical stimulation therapy
When it comes to finding relief from muscle pain or nerve damage, electrical stimulation therapy can be a highly effective treatment option. However, in general, professional help is necessary to ensure the therapy is safe and effective. If you are experiencing any complications such as skin irritation or muscle spasms during the treatment, it is best to consult with a professional. Additionally, if you have a pre-existing medical condition like heart disease or epilepsy, it is advised to seek professional guidance before starting any new therapy. Remember, while electrical stimulation therapy can provide many benefits, it is important to prioritise your safety and well-being by consulting with a professional.
Conclusion
Electrical stimulation is now commonly used in rehabilitation to help improve patient outcomes. It can be beneficial for improving muscle strength, range of motion, relieving pain and healing wounds. The types of electrical stimulation used in rehabilitation are many. However, it's important to make sure the treatment is being administered by a professional with appropriate expertise or knowledge as with any type of therapy there may be potential side effects and risks associated with it. Ultimately, if you are interested in learning more about electrical stimulation or starting a program for yourself or a loved one, it's best to speak to your clinician about what option might be right for you and the results you hope to achieve.
Some related articles
Can Electrical Stimulation Treat Chronic Wounds?
5 Benefits of Using FES Bikes for Rehabilitation and Fitness
What is the purpose of functional electrical stimulation?
What is the success rate of electrical stimulation for pain?
FES and Peripheral Nerve Injuries: Exploring Benefits of Functional Electrical Stimulation
Is 20 minutes of FES Cycling good enough for health gains?
Denervated muscle rehabilitation with the RISE Stimulator
The Benefits of Functional Electrical Stimulation for Rehabilitation