Fewer signals and still pain? Why does polyneuropathy hurt?
In polyneuropathy, damage occurs in the nerves, resulting in fewer signals from the periphery (mostly hands and feet) reaching the brain.
The fact that this causes pain is actually paradoxical. Because actually, getting fewer signals to your brain should mean you feel less sensations in general and not more pain.
Also, it is quite common that polyneuropathy does not actually cause pain, but simply causes you to not be able to feel your toes, feet, and fingertips anymore. So why do people with the same disease have completely opposite symptoms?
In this article, I explore the question, "Why does polyneuropathy hurt?"
A very detailed article on self-help for the pain can be found here: Pain in Polyneuropathy and what you can do about it.
Feelings are made in the brain
For example, in order to feel touch on your toes, the pressure on the toes must be sensed by a nerve. It reports its perception by sending a signal to the brain.
There is an brain area for each body part that receives and interprets the signals. It is through this interpretation that the feeling we perceive as touch is created. This interpretation of the signals also determines exactly how a touch feels.
Whether one feels a touch as a light caress or strong pressure, as tickling or scratching, depends on how the signals from the nerves are interpreted in the brain.
So the pain originates in the brain, not in the feet!
Polyneuropathy affects the brain!
If a nerve is damaged by polyneuropathy, it sends misleading signals to the brain.
This means that if, for example, a light touch was previously reported, this signal is now altered by the nerve damage. What still arrives in the brain can no longer be interpreted as clearly as before because the data transmission is disrupted.
It is similar to interference with cell phone or radio reception: The receiver no longer understands the signal and instead of a clear sound, only crackling and noise arrive.
Hypersensitive brain areas cause pain
The nervous system responds by making the receiver more sensitive. The brain areas that receive and interpret the signals from the damaged nerve become more sensitive, literally. They develop a higher basic activity, more nerve cells grow there and the response to the nerve signals is increased.
This has the unpleasant consequence that normal everyday stimuli are felt excessively strongly and trigger pain. That is why, for example, even light touch can hurt.
If you feel pain as soon as your feet touch the floor or even the bedsheets touching your feet triggers a painful pressure, this is therefore not only due to problems in the feet, but especially in the brain.
The same applies, by the way, even if you feel uncomfortable heat sensations, tingling or other types of discomfort:
Polyneuropathy causes problems in the brain, not just in the hands or feet!
If you want to read more on the topic, here is a scientific study that describes the connections: Domingues et al. 2018
Brain training reduces the pain
If you train the brain, you improve polyneuropathy!
This is also the reason why it often does not help to work on your the feet or the hands in order to reduce the pain. Some people can get some relief by using foot baths and creams or applying other treatments. But that only helps in the short term, the pain will still come back.
A better way to manage the discomfort is to train the brain to reduce hypersensitivity. Balance training is excellent for this purpose. So this means to practice standing in unstable or even wobbly positions.
Because in order to keep your balance, you need to be constantly aware of your body and feel it very precisely. You also need to respond appropriately to sensations such as pressure on the soles of your feet. This improves the body's perception and makes the brain's work more efficient.
Maintaining balance is one of the most complicated tasks we face in everyday life - even if we often don't realize it. It is necessary to perceive, evaluate and react appropriately to movements of all parts of the body, their position in relation to each other and the tension of the muscles with the highest accuracy.
This means that in order to maintain balance, signals from the body must be constantly received, transmitted and interpreted.
This can lead to a reduction in pain.
You can find practical exercises for this here: Polyneuropathy pain and what you can do about it
87% of patients report less pain and discomfort after training
according to Streckmann et al. 2014
Training compensates for nerve damage
In a study at the University of Freiburg, such balance training was tried out with people suffering from polyneuropathy (Read the study here Streckmann et al. 2014).
As expected, the training improved the patients' balance. More importantly, 87.5% of patients reported fewer symptoms of polyneuropathy. That is: the pain and discomfort got better! In the control group, which did not exercise, not a single patient reported improvement in symptoms at the same time point.
By the way, it was measured whether the nerves in the legs of the patients recovered. For this purpose, the nerve conduction velocity was measured, by which neurologists can recognize how severely a nerve is damaged. The measurements showed no change as a result of the training, even though the symptoms got better.
This means that the improvement of symptoms did not originate in the damaged nerves in the feet or hands, but in the brain!
The brain is the most adaptable organ!
This is excellent news. Because it means that the nerve damage that occurs in the feet or hands can be compensated for by exercise that stimulates the brain.
Because, unfortunately, there are still few ways to heal the nerves that are damaged in polyneuropathy. But if you can improve the "data processing" in the brain, you can still reduce the pain!
Surprisingly simple exercises
If you now suspect that such a training is highly complex and difficult to implement, don't worry.
Training your balance is easy. You can easily perform such training by yourself at home - if you know how to do it.
The most important thing is to choose the right level of difficulty. Because, of course, someone who walks on a walker can't exercise at the same level as a healthy fit person.
On my page "Exercises for Polyneuropathy" you will find numerous exercises in various degrees of difficulty to try out. You'll also find all the background information you need to get started right away. Even more specific instructions for training against the pain can be found here: Pain in Polyneuropathy and what you can do about it.
You can also order a book with exercise instructions.
Muscle pain and nerve pain reinforce each other.
The pain in polyneuropathy often comes from the muscles!
Very often, however, the pain is not only triggered by the nerves - even if you suffer from polyneuropathy. This is because pain from the muscles is very often added to the pain caused by the nerve damage. Muscles that are tight can cause incredible pain.
Most people have already experienced this themselves. What not everyone knows is that in some cases, muscle tightness cannot resolve by itself and therefore cause permanent pain. And this can happen without the patient noticing that there even is a tight muscle.
This is because the muscle tightness can form tiny cramps, often only a centimeter in size. Nevertheless, they can cause tremendous pain in entire parts of the body. This is medically called Myofascial Pain Syndrome and it is one of the most common causes of pain.
Referred pain from the muscles
This problem arises particularly often when the interaction between muscles and nerves no longer functions properly and the muscles are overloaded. This is particularly common in polyneuropathy. So one reason why polyneuropathy hurts is that the nerve damage results in problems in the muscles.
Very often the nervous system is not able to relate the pain to the correct area. The pain is then felt in a different place than where the actual problem is located - this is called referred pain.
This happens especially often with muscles in the lower leg. The pain triggered there is then often felt in the feet. For example, problems in the long toe flexor (flexor digitorum muscle) often cause pain in the toes, even though the muscle itself is located in the calf.
Nerve pain and muscle pain are indistinguishable
Unfortunately, it is practically impossible to distinguish whether the pain you feel is caused by nerve damage or muscle problems. Because your nervous system only tells you that pain is there, not which structure is reporting it. However, my personal experience is that almost all patients with polyneuropathy have an additional problem in their muscles.
This actually is good news! Because we know how to improve the function of the muscles - through training. So if the nerves can't be cured, at least the muscles can be worked on.
Muscles are usually ignored in polyneuropathy
Unfortunately, few people think about the fact that you could help yourself by working your muscles if you suffer from polyneuropathy. Polyneuropathy is a nerve disease and the connection with the muscles is not that obvious.
Therefore, patients are very rarely told that treating the muscles can help with the pain, even if it does not cure the polyneuropathy.
Learn how to help yourself!
In addition, the muscle problem cannot be solved with medication or a few simple physiotherapy techniques. It is possible to treat the muscles with exercise, stretching and massage, but the nerve damage in polyneuropathy makes treatment much more complex and difficult than in other patients.
Therefore, it is very difficult for therapists to make real progress. Especially because there is not enough time and the therapy sessions are too short. Therefore, the best solution is to learn what you can do for yourself.
Therefore, in my Pain Relief Set you will find the exercise guide "Exercise for Polyneuropathy" with numerous exercises for training balance and body awareness. For the treatment of the muscles you will receive the book "How to treat your own foot pain", describing the massage and stretching of all relevant muscles of the feet and lower legs.
So, with the Pain Relief Set, you get everything you need to help yourself against the pain of polyneuropathy.