The Truth About Pain

When sitting down to write this article, I googled pain. I thought it would be interesting to see what sort of information the public would be getting when researching this term online. The definition that comes up, very prominently displayed, is “physical suffering or discomfort caused by illness or injury.” My guess would be that not too many people would object or find fault in this definition. The problem is it’s not true or at least not the full story. Untrue and unrealistic beliefs about pain, such as the definition above, have been shown to negatively affect one’s quality of life and actually increase the overall experience of pain. It has been consistently proven, that an accurate understanding of pain and how/why it is produced can make a huge difference on one’s pain experience and recovery. 

If you were to compare the definition above to the most recent definition in the medical and pain science world, it is actually quite different. We define pain as “an unpleasant sensory or emotional experience associated with actual or potential tissue damage.” The highlighted areas have been completely left out of the google explanation and yet they are such important parts of the pain experience. Read on, with an open mind, to learn some interesting truths about pain. 

All pain comes from our brain. 

You heard that right. All pain comes from our brains 100% of the time. 

All of our tissues have sensors. These sensors send a constant stream of information to our brain throughout the day. They send signals when we move, when we are touched, or from changes in temperature, to name a few. These signals in and of themselves are not pain, but purely a warning signal that something is going on in our bodies. 

Our brain then plays the role of sorting through all of these signals, deciding which signals are relevant and useful, and which can be ignored. It quickly synthesizes all of this information to makes split second and subconscious decisions about whether it perceives this signal to be dangerous. If our brain thinks it is dangerous and we should pay attention, it produces pain to get us to change our behaviors.

Pain is useful and necessary.

If you are currently in pain, you may struggle with this statement, but pain is actually very necessary and important to life. It is meant to warn us when we are nearing the level of tissue injury and when to pay attention to something that is happening in our tissues.

Some individuals are actually born with a condition that does not allow them to feel pain. They still have sensation (ie. can tell the difference between hot and cold or when something is touching them), but are unable to tell when that same stimulus is actually hurting them. Due to this, they tend to have an accumulation of wounds, injuries, broken bones, potentially unidentified health issues, and unfortunately, it also tends to shorten their lifespan. 

Pain does not equal tissue damage.

Sure, pain is often produced in the presence of actual tissue damage (ie. when you break an ankle), but it is also produced with “potential” tissue damage. For example, take one of your fingers and slowly begin to bend it backwards. You’ll reach a point when it actually begins to hurt. Your body hasn’t undergone any tissue damage, but your brain has perceived the potential for damage and is sending you a warning signal to stop.

There have been documented cases where people have had major tissue damage (ie. leg bitten off by a shark) and they didn’t feel pain. In other situations, like a papercut, there is very little tissue damage, but it can cause a great deal of pain. The same is true of arthritic joints. Some people have been found to have severe arthritis on x-ray, but actually have very little or no pain. Others with minor joint changes on x-ray, can have severe pain. These examples continue to show how pain isn’t equivalent to tissue damage, but rather a complex combination of factors.

Pain is processed differently depending on how long it’s been present.

Acute pain is a type of pain that has been experienced for less than 3 months. This is the type of pain we see initially after injury to our tissues. Most types of tissues heal in approximately 6-8 weeks. If your pain began due to actual tissue damage, in theory it should go away within this timeframe. Often this is not the case and the pain persists much longer. 

Chronic pain is any pain lasting longer than 3 months in duration. It has been shown that pain persisting into this timeframe is more complex in nature. There are actually changes that occur in both the tissues and their sensors, as well as, the brain that allow us to perceive pain more easily. In a normally functioning pain system, the pain warning system should kick in just before we reach the level of tissue injury. In chronic pain, this pain warning system starts to become sensitized and it kicks in long before we near the potential for tissue injury. Basically, we start to feel pain both easier and earlier than we should. Often, even with totally safe, non-threatening movement. 

At this point, the initially injured tissue is likely healed and stronger than ever. Joints and muscles around the area may still be stiff and/or weak and contribute to sending increased signals to our brain for processing – this is something your physical therapist can easily help to target. The tissues in the area also step up their search for things to be concerned about. They become hypervigilant, looking for any potential trouble, as well, the nerves in those areas actually sprout additional endings making them more sensitive to stimulus.  So basically, the tissues begin to send extra warning signals to the brain for processing which often results in increased pain production. This type of pain should actually be treated differently from acute pain and exercise/strategic movement becomes an extremely important part of restoring the normal function of the pain system.

Your beliefs and emotions will affect your pain.

We can actually predict those that will go on to experience chronic pain. Not by the nature or degree of injury, but actually by their beliefs about pain. Those people who catastrophize and think the worst about their pain are strongly correlated with those who remain moderately to severely disabled after a years’ time. 

Even when undergoing surgery, pre-existing negative beliefs about pain was one of the strongest predictors of poor surgical outcomes. Not the surgeon, not the type of techniques, not their pre-existing physical status, but their thoughts about pain. Powerful stuff, and something physical therapists can have a great influence on through education and discussions surrounding pain.

Other things, such as general stress, anxiety, or depression can also have a huge influence over our pain. When we are operating in these states, the natural chemicals that are released within our bodies change. These chemicals continually circulate through our bodies and bathe our tissues. This change in the chemical balance at the tissue level actually amplifies tissue sensitivity and increases the signals sent to the brain. 

These states also cause changes to how signals are processed in the brain. Over time, the filtering mechanisms that are normally in place that turn away redundant or irrelevant signals, leave. Because of these changes, our brain actually receives an abundance of information to process and make decisions upon. We also start to develop bypass loops in our brain that skip considering the discriminatory aspects, such as where the signal is coming from or how often, and instead, jumps straight to the emotional aspects of the signal, such as have I done this before and did it hurt? So, the brain subconsciously, starts making decisions and creating pain without a balanced consideration of all the signals it is receiving. 

Your physio may encourage you to engage in a relaxation practice such as meditating or deep breathing. This is an easy to implement self management technique that has been shown to decrease pain with time and practice.

Sleep is important.

In those people with chronic pain, more than 75% have been shown to have disrupted sleep. Contrary to what many may assume, this poor sleep is actually considered to be a driver of persistent pain rather than a result of the pain.

If you are struggling with a good night’s sleep, here are a few tips to consider:

• Follow a consistent routine of going to bed and awakening times and avoid daytime napping
• Engage in some morning or daytime exercise
• Avoid alcohol, nicotine, and caffeine for at least 6 hrs prior to sleep
• Lower the lights at least a hour prior to bed and avoid any screen time during this period
• Practice a relaxation technique of your choosing

All pain is real.

After reading all of this, you may be thinking “so you’re telling me this pain is all in my head.” No, I’m telling you that we believe you. You have pain. It is very real and as you say it is. But, we also know that pain is complex. It comes from an intricate interplay between both tissue and brain factors, but yes, in the end, all pain is produced from the brain. 

The great news about pain….

We can change our tissues. We can increase mobility in tight muscles and joints. We can strengthen weak muscles. And in turn, we can alter the input these tissues are sending to the brain. 

We can change our brains. The brain is one of the most plastic (meaning changeable) parts of our bodies. It can be rewired to respond differently to the signals coming from our body. We can calm our heightened nervous systems. 

Each individual with pain has some control and can do things to influence their pain experience. This may take a variety and often a combination of forms: pain education, exercise, decreasing stress/anxiety/depression, or changing our automatic thoughts regarding pain, to name a few. A STRIDE Physical Therapist can help guide you on this journey, help you to further understand your pain, and aid you in reclaiming your life!

– Laurel, PT

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