This topic has come up recently in clinic a few times so thought I'd pop down some thoughts and resources for you guys. About how much of pain is due to actual tissue or structural damage vs how much is due to someones perception of pain or the their tolerance of pain. Why is it that pain can feel so very real even when the risk of injury has gone, like the pain after a back spasm. You do a certain 'risky' movement and you get pain, but why does that persist after you've stopped doing the action and theres been enough time to heal? Or why does a relatively minor injury result in significant and lasting pain? Why is our pain tolerance for the same injury better or worse on different days?
Let me run through some scenarios we've recently had in clinic:
Patient X - Knee Pain
Patient X has ongoing knee pain. As a rule the pain has not been significant, and a flareup would last no longer than a day or so, easily managed with ice and rest. Patient X recently received a diagnosis of mild osteoarthritis in the knee and since then has been struggling significantly with increased pain, unable to manage it as before and has had to significantly reduce their daily exercise in order to control the symptoms.
Patient Y - Back spasm
Patient Y was being treated for restrictions in their upper back. Spinal mobility was reduced causing pain at night but did not limit daily activities or heavy gym workouts. Patient Y is a single parent and their symptoms improved significantly over a 2 week period, which coincided with a holiday and their child spending a week with the other parent. When the patient returned to clinic after the weekend they were in intense pain, with limited range of movement and in a very sensitised state (emotional, exaggerated pain response, very reactive to touch etc). Over the weekend they had gone to the gym and worked out as usual, but at the end of the session experienced an extreme back spasm. Upon questioning they revealed their child had returned home and they were finding it difficult to manage their behaviour as well as having been disappointed with their own performance during the gym session.
What to note is that both patients experienced a real and significant increase in pain due to a change in circumstances completely unrelated to mechanical stress. Their ability to relate to pain, and 'cope' with its presence, was somehow reduced by receiving their diagnosis or by being stressed.
How much of pain is due to actual tissue damage vs perceived tissue damage?
The interesting thing is that these cases are by no means rare. In fact I would say 9/10 patients that we treat in clinic have some form of psycho-social or neurophysiological factor compounding their pain.
Factors other than mechanical damage are limiting recovery or increasing the level of pain and restriction perceived.
The majority of injuries self-limiting, meaning that with no intervention and with time the injury will heal by itself. This includes all injuries from mild ankle sprains, to cuts & grazes, post-exercise muscle soreness, muscle strains, spasms etc. However when an injury has been present for more then 6 weeks it is classified as chronic; which describes most of the patients we see in clinic. And when an injury is chronic, by its nature, something is limiting its recovery.
Pain is not a simple topic, many factors influence our pain tolerance and perception of pain; the longer pain is present the less likely that is it simply due to mechanical damage.
These two TED talk videos (about 15mins each) really do a good job of explaining some of the mechanisms behind our pain. The main takeaway is that pain is a perceived threat, which can be increased or decreased depending upon your emotional, psychological and physiological health. Not just your musculoskeletal health.
Which means at least half of your pain is indeed, just in your head!