Today I want to talk about chronic pain and what could be some potential contributors as well as some treatment methods. I will mainly be talking about central sensitization and nociplastic pain (don’t worry I will explain what those are in the next paragraph). I want to make it very clear that these are concepts, and not truly known mechanisms, since the nature of them makes it difficult to study in humans. Before I get into the definition, these two concepts would fall within chronic pain1 and so I will be talking about treatments for these concepts and chronic pain together.
Central sensitization and nociplastic pain
At the core, both of these concepts describe pain that has no actual damage or inflammation accompanying it, but rather you have general areas of pain and hypersensitivity (normal things are painful or a bigger pain response than normal to painful stimuli).2-5 Central sensitization kind of goes a step further to try to explain the mechanism behind the classification. In central sensitization your brain and the neurons in your spinal cord become more sensitive to pain, thus making it easier to feel pain and potentially making it a higher intensity.2-5 Kim5 described it as your brain “turning up the volume” for pain, and one way that I like to describe it is that your body is on high alert and looking for pain. I want to point out is that the hypersensitivity can make normal tasks painful and thus make you afraid of doing certain movements,6 which can negatively impact your quality of life. Basically to sum it all up, you feel pain more often, and the pain can be worse!
What can cause it?
Now that we have a brief understanding of the two concepts, how do they come about? Well, sensitization may occur after an injury, prolonged exposure to pain, surgery, osetoarthritis and more.2,5,7,8 Expanding to chronic pain in general, other risk factors include stress, poorer sleep, and physical inactivity,9-12 with work stress being a strong independent factor that outweighs physical activity.12 This is an important point for guiding your treatment and looking at things that are not your pain, but may actually be playing an important role in your pain. Sometimes working together with your health care provider to come up with strategies that change your lifestyle can be the most impactful, and where the treatment focus should be.
An important point to consider for the aging population with osteoarthritis (OA), is that chronic pain in the form of sensitization or nociplastic pain can often accompany hip and knee OA.8 This furthers the point that the physical changes as seen with OA may not always be the cause of pain, and increase the importance of education and exercise as part of the treatment.5,8,13,14 It is known that some inflammation in the joint lining is a sign of OA13-16 which may be one of the influencing factors for the sensitization.8 I would also go as far to argue that the outdated and inaccurate view of OA as wear and tear could lead to fear of movement and also create a learned pain response to movement, thus increasing the amount of pain experienced in this condition.
Continuing with this point, people who have sensitization and OA, typically also have higher expectations for surgery, which results in worse outcomes after since their expectations are often impossible to meet.5 Again, this point is highlighting the importance of managing expectations through education. This education isn’t a quick two minute talk about what osteoarthritis is and what is going to happen in the surgery, it needs to go a lot deeper than that. You need to gain a much deeper understanding of what is happening, why it may be happening, EVERY treatment option, and what to expect as an outcome. If you are not receiving this from your practitioner then they are not properly educating you.
How can chronic pain be treated?
Now that my little rant is over, what should your treatment look like? First and foremost it should be specific to you and your goals, with a focus on enhancing your quality of life and what you can do, rather than decreasing pain.4,17 Understanding that the focus should be on increasing what you can do is a large part of the education, which is the other main component of treatment.4,5,17,18 Before I lose you, let me explain why the treatment focus should be on increasing what you can do, rather than on pain reduction. Pain is tricky and it may be difficult to decrease the total amount of pain that you feel in a day;4,17 however, by increasing what you can do, your pain becomes a relatively smaller part of your life. In other words, your pain hasn’t changed sizes, but your life has become much BIGGER.
Also, addressing the lifestyle factors of sleep, stress, and physical activity can play a role in improving chronic pain.4,6,9-12,17-21 I won’t go into stress reduction and sleep treatments in this article, but i will talk about the benefits of exercise!
It has been shown time and time again that exercise is helpful for chronic pain,6,19-24 and it can actually also improve your sleep!20,25 That is a nice added bonus from exercise. Often the mechanisms by which exercise is thought to help you with chronic pain is its ability to release opioids (feel good chemicals) as well as change how your body feels pain.6,19,20 One thing that isn’t talked about in the studies that I would like to point out, is that exercise can also be an avenue for education that shows you that certain movements are ok and that you are strong and capable!
What kind of exercise?
Ok sick, I’m sure that you have already heard that exercise helps, but is there a certain type of exercise that is more beneficial for you? The highest quality evidence shows that the answer is no20,23 which is great and allows for freedom when individualising the exercises. There are some papers that show certain types of exercise could be more beneficial,21,24 but when I dove deeper into the articles and looked at the interventions, I noticed an interesting trend. The types of exercises that showed better results were typically ones where the patients were working harder. This means that they were doing more than just a few clamshells or deadbugs. Studies that looked at resistance training and used protocols that more closely fit criteria for hard sets26 had better results than the exercises that didn’t.27,28
To me, this shows that the exercise interventions may just need to be difficult enough in order to produce change. This means that you can do whichever exercise you enjoy and is meaningful to you, but you have to do it hard enough. To use a cliché: if it doesn’t challenge you, it doesn’t change you. This doesn't mean that you have to train as hard as a pro athlete, but just that the exercise should be harder than what you typically do in your daily life.
To sum it all up, chronic pain is weird and can be quite debilitating. A potential mechanism of chronic pain is central sensitization in which your body gets better at feeling pain. This sensitization can come about from many different things, but the main treatments for it are: education in order to help you understand what is going on and allowing you to interact with your pain in a different way, managing stress, improving sleep, and doing exercise. The type of exercise doesn’t matter and it should align with your goals and what is meaningful to you!
Change can take time, but I hope that this article has helped you to gain a better understanding and can also help you improve. As always, it’s time to go out and move!
*This is an informational resource and not medical advice, please consult your healthcare practitioner for diagnosis, treatment, and guidance.
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