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What does a pain signal actually mean?
Before we can really tackle the idea of listening to your body fully, we need to talk about what pain actually means. If I asked you to write down what pain means, the majority of people will likely say something like:
“pain is a sign that something is wrong, that something is happening in my tissues that I want to avoid”
Whilst this may be the case in some instances, it’s certainly not accurate for a lot of painful scenarios, and really the research tells us it’s mostly not accurate at all. I’m going to show you what I mean by that through this article – and hopefully the information here will help to reform what you think pain actually signals.
Different sensations and meaning.
It’s useful to know what a ‘tingling’ sensation could mean, or a ‘sharp’ one, and so we’re going to open that conversation here. Before we do, it’s important to understand that pain science is hugely complex and that the next section here is only a part of a big pain-story, so make sure you keep reading. Pain science cannot simply be reduced to a list of “this pain equals this”. Because not only is most pain not simple, it’s also not just one thing.
To start with we’re going to look at the 3 main classifications of pain, before we then look at types of sensations:
• Nociceptive – this specific term refers to pain signals that are being transmitted by nociceptors (special receptors) in the tissues of the body, as in, they’re detecting something that might be going on in the tissues themselves.
• Neuropathic – this type of pain is where something is going on directly with the nerve. It could be a medical condition (like multiple sclerosis for example), or it could be that a nerve is being impinged by a joint, or has been impacted from an external force.
• Algopathic – this is also called “pain without a known cause”. It encompasses the rest of pain syndromes that aren’t either of the other two (or at least we don’t know if they fit into one of those two buckets), and often are beyond the scope of what current pain science can understand. Fibromyalgia is the queen example of this type of pain.
For the rest of the article, we’re only going to be talking about pain that doesn’t have an ‘obvious’ cause. Even though a lot of information exists to help us understand a pinprick pain of a needle entering our skin, a sprained ankle or a punch in the face, we’re not really going to focus on that here. Not that apparently “simple” pain is actually simple at all (because some people can cop a punch in the face no problem and others cannot), but right now we’re setting our sights on the even-less-obvious pains that arise from seemingly unknown or seemingly innocuous circumstances.
Types of sensations
Now, let’s discuss possibilities for sensations of particular ‘type’ characteristics. It is probably beneficial to have already read through a previous post I wrote “A Comprehensive Guide To Describing Pain: Helping Us Help You”. This is where you can find the list of types of pain that we’re going through below.
Types of sensations and how they could be classified:
• Sharp – these sensations can be neuropathic in nature and we most often assume this to be the case, such as in a nerve compression. Yet true nerve impingement is not as common as you think (read this for the example of carpal tunnel syndrome). So actually, a lot of sharper sensations fall under the algopathic label. Remember, right now we’re talking about sensations that aren’t tied to an obvious insult – not the broken bone that gives you a sharp sensation.
• Dull – is often a nociceptive sensation and we can usually expect more persistent dullness as a result of that. This is typically something we can expect from non-specific low-back pain where nerve endings/nociceptors are reporting that something in the tissues is “off”.
• Tingling – another sensation that we often refer to as nerve-pain (neuropathic), but again is typically more of an algopathic one, if not nociceptive. An example of this is having “slept funny” on one arm and during the day the fingers of that arm are tingly. You might be surprised to know that this is often less about nerves being compressed upon exiting the spine, and more about trigger points within the tissues, and joint distraction.
• Burning – This sensation is something we are likely to encounter in nociceptive or algopathic sensation communications. An example of nociceptive burning is putting capsaicin or another chemical irritant on your skin. Another example is the sensation often described with “sciatica” that is actually mostly misdiagnosed piriformis syndrome, which is more algopathic.
• Numbness – is actually a great example of neuropathic sensation, and one that is possibly our best indicator of direct pressure on, or impingement of, a nerve.
• Throbbing – is more often than not, a nociceptive-derived sensation – one where inflammatory mediators have irritated nerve endings, similar to a nociceptive burning sensation.
To reiterate, I’ve just noted the more common interaction with the types of sensation and their classifications. This is not always going to be the case in every instance. Just a good number of them. I’d also like to highlight that there hasn’t yet been any comment on what each of those sensations might mean in terms of “good”, “bad” or “other”.
So again, what does pain mean?
All of the types of sensations could mean something, and all of them could also mean nothing. Pain is like that. That’s because pain is entirely a cerebral event. The MEANING of sensation is derived from the brain interpreting those signals and either ascribing significance to them or not.
In that case, can dull pain actually be signalling something wrong with the tissue? Yes, it certainly can. It could also be absolutely nothing at all. Or it could have been something to set it off previously, but nothing physical anymore.
This means that our whole idea that “pain is a signal telling us something is wrong”, needs to be re-evaluated and deconstructed. Because it might, and it might not – and most often, it’s the latter.
But we have to be careful, because we don’t want to throw the baby out with the water. It’s a complicated situation, as you may be starting to feel (even if just by not getting a solid answer).
Why could pain mean something?
The sensation of pain may indeed be telling us something worth us knowing – it may actually be signalling that something is wrong and needs to be addressed. Our brain does this to keep us alive – when we feel intensity, we often do something about it. And if something were indeed wrong (to a medium degree), it would be advantageous for us to actually take action and make some changes.
So, why could pain mean nothing?
Because perhaps something hurt a while ago and has since become centrally sensitized or in the shorter-term, peripherally sensitized. Either meaning that we’re registering a sensation in our brain simply because it’s used to it after a long period of time, or we’re still getting messages from the periphery because of lowered stimulation thresholds of nociceptors and a release of inflammatory mediators that weren’t actually needed but where released anyway just in case. Also, there’s this thing when actual injuries of life-threatening severity do occur, they can often be painless (like this).
Want to know something even trickier?
Here are some things that complicate our ability to interpret the meaning of pain or intensity of sensation:
• The location of pain and severity of sensation often have nothing to do with the degree of physical insult. (reference)
• Sleep deprivation plays a role in how sensitive we are to stimulation (reference)
• Diet – the food we eat and it’s composition also influence pain perception (reference)
• Stress – I don’t really think I need to give you a source for this one because I’m pretty sure you already agree, but here you go anyway (reference)
• The beliefs we hold about pain play a huge role (whether conscious or unconscious) (reference)
• All past experiences in life…including but not limited to physical and emotional traumas. (reference)
**Senses like vision and touch would normally also be included here, but remember we’re only talking about pain from unknown or unclear sources right now.
But just one sec.
Something I’d like to draw your attention to for just a minute, is that in our list of sensations and what they could be signalling, there was really only ONE sensation that is almost a slam dunk for telling us that nerve impingement is happening. Just one. That was numbness.
However, a lot of the time, we hear people saying (or if we don’t yet, keep an ear out for it) that they have nerve impingement here, there and everywhere. Now, that’s not to say that it isn’t happening in some instances (about 12% of the population, so certainly not insignificant), however nerve impingement and compression is just not as common than a lot of people think. And this is actually a really good thing. (It’s even not really all that more common in those who have had motor vehicle accidents. Reference).
Slight diversion –
It’s a really good thing that neural damage isn’t as common as we believe because neuropathic pain is the one we want to be most cautious of. This is because neuropathic sensation can lead to chronic pain more often than nociceptive-driven sensations. So perhaps it’s over-diagnosed in order to just make sure, because it has greater clinically significant implications if it’s made worse. Now, nerves aren’t all that delicate – let’s be clear. Not much in the body could really fit under that classification. However, they don’t have the same mechanisms of repair that for example muscles do, and they have to compete with infiltrating scar tissue (reference). This type of thing really needs to be evaluated with medical imaging so that you’re able to see the physical impingement.
Now, back to the main point…
Why do I want to draw your attention there?
Because for the most part, people use the phrase “listen to your body” because they believe that intense sensation signals that something bad is happening or is about to happen and therefore must be avoided. And whilst it might indeed be signalling that, we see that there’s really only one instance where we don’t want to really challenge that theory. Meaning, that a majority of people who have pain, don’t really need to be taking rest so often. And this is important because…
Movement and manual therapy are often critical elements to the reduction and possible removal of that pain. Yet, if we’re continuously scared to move, or even encouraged to rest as an actualization of “listening to your body” (which is mostly how it’s understood by people), we substantially cut our chances of actually getting out of that pain.
I know this can be a really challenging, and brain-straining to read. We’ve been told our entire lives that when it hurts, we need to stop doing it.
But more and more research is telling us that sensation is actually not the enemy, and it’s also not always even the real messenger. And more and more, movement and manual therapy are being shown to be the things we need rather than the things we need to avoid, even when there’s some intensity to sensation.
To help, you could also read research like this:
– https://www.researchgate.net/profile/John_Otis/publication/294276376_Potential_ neurobiological_benefits_of_exercise_in_chronic_pain_and_posttraumatic_stress_ disorder_Pilot_study/links/56e1883108ae23524090afbe/Potential-neurobiological-
benefits-of-exercise-in-chronic-pain-and-posttraumatic-stress-disorder-Pilot-study.pdf
– https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4534717/
– https://www.oarsijournal.com/article/S1063-4584(19)30902-1/fulltext
– http://www.thblack.com/links/rsd/ClinJPain2015_31_108_Exercise4ChronPain.pdf
So, after all this, what does it mean?
No, it doesn’t mean that we can bring back the idea of “no pain, no gain”. That is staying in the history books still. It means that we need to stop always using pain/intensity as the indicator for determining our next actions, especially as an excuse to rest/do less, and instead develop a greater vocabulary around sensation in order to be able to support the reduction in pain in the best possible way over time, backed by science and shared with others through education. It’s also important to note that if we’re really listening to the “needs” of the tissues, we’d actually be moving a lot more, even in order to retrain our pain system.
It doesn’t necessarily mean scrapping the saying. It means teaching people what they’re listening for, and what they might be able to do with that information on sensation. This also means taking the fear OUT of movement and manual therapy settings.
Thoughts or questions? Hit me up below.