Most of the time we think of pain as a bad thing, as something detrimental to our lives that we would rather not experience. Nobody likes it when they kick their toe on the skirting, or when they find the edge of the bed with their shin in the dark. But what would happen if we didn’t feel pain when we did things that are potentially very harmful to our bodies? What if we broke a bone, or punctured a lung? How would we know that we even have these injuries, and more importantly, how would we be able to reduce or manage the potential harm by responding to pain if it is not there?
The human body is an amazing thing. Our nervous system is so sophisticated that it regulates our bodies based on the information it receives from millions of nerves, which it integrates, processes and acts on without any conscious thought. This is essentially how we feel, or don’t feel pain – among many other things. Interestingly, there is no single type of nerve that senses pain. What we do have are nerves that can detect things like pressure, temperature and texture, which are then transmitted to our brain via the spinal cord. Here, all of this ‘data’, along with a lot of other information about the context of the situation we are in (sights, smells, what we hear) is integrated and processed as evidence regarding the threat level of a situation.
After weighing all of the many inputs received against each other, a decision is reached regarding the ‘danger level’ of the situation. If the brain decides that the evidence suggests serious potential for bodily harm, then we experience pain sufficient to force protective action. That may be in the form of applying pressure to an open wound or going to the doctor for an investigation into abdominal pain.
If, on the other hand, the decision is made that there is not sufficient evidence of serious threat to the body, or that other inputs are more important than the threat of damage, then pain will not be experienced. A useful example of this is playing an important sports match and rolling your ankle. The need to win and continue playing is a stronger driving force than the threat of damage to your ankle, so you continue to play without experiencing pain. At the end of the game when you no longer have the driving need to play and win, you may start to feel pain in the ankle. This is because the input to the brain has changed, and greater evidence of danger instigates a sensation of pain to prompt protective action.
I suppose you could then say, pain is protective, or pain is contextual, or pain isn’t pain until it reaches the brain (thanks Butler and Mosley), and really, all of these things are true. We need pain to stay healthy, we need it to prompt action, and whether or not we feel it depends on what the driving factors of a situation are.
If you are interested in exploring the science in more detail, Lorimer Moseley and David Butler are two brilliant physios who have pioneered a vast amount of the research and practical application of pain science and education used by therapists today. We sell their book 'Explain Pain' here at the clinic as it's a wonderful resource that only makes it easier to understand these concepts and apply them practically to your own life or those of your loved ones.
Written by Rhyan Eason, Physiotherapist.
Rhyan has completed further education in neuromuscular dry needling, Clinical Exercise education, and pain science and regularly attends short courses covering all areas of practice. She enjoys the problem-solving aspect of her role and loves educating patients on how to help themselves through injury and rehabilitation, with an overall focus on self-empowerment and independence.