Why Does it Hurt?
Why does it hurt? I am asked this question on a daily basis. In the treatment room, I try to simplify it as much as possible, but the real answer is quite a bit more complex. To really get an understanding of why, it would be best to start with understanding how essentially our brain and nervous system works. The complexity of pain makes it a very difficult thing to treat and work with. On a positive note, it also means that some factors are more treatable or manageable than others, but only if you have a true understanding of how pain really works.
Here are the basics: We have sensors called nociceptors that respond to stimulus. When activated, these sensors send warning signals from the body to the spinal cord via nerves. The signals from the nerves within tissues alert that there is a potential for tissue damage. The nociceptors then send that signal to the spinal cord for further processing. Your spinal cord is like a middle man who can decide to send the signal up to the brain or to leave that nociceptive alert at the spinal cord. This means there could potentially be something “dangerous” going on, and you might not have a clue!
So with that basic understanding of how the pain response system works, now it is time to change our mindset – when we first think of “pain” or when we even feel “pain.” We really need to stop thinking of pain in terms of causes or cures. We’re all guilty of saying to ourselves “It’s all coming from the ____, I know it!” I’ve done this myself, but sadly, we’re almost always wrong.
We have many non-specific sensitivities to pain. Pain is purely an alarm. It is a very unreliable sign of what’s really happening. Is it a fire? Is it the carbon monoxide detector? Is it the neighbor’s alarm? We have no idea!
We have assumed for a very long time that the most common cause of musculoskeletal pain, such as a “structural” or biomechanical problem – a slipped disc, a short leg, etc. – is the root cause and only explanation for that pain. For decades we’ve been told that the structural problem is causing the pain, but that explanation is also evidence that there is a lot more to pain than just screwed up tissue.
Patients are often given the alarming idea that the slightest crookedness/out-of-place joint is “serious.” As humans, we are designed to compensate, designed to figure out how to go about our days with no concept or feeling of pain so we can survive. Did you know the world record holder for the deadlift has idiopathic scoliosis! (Lamar Gant in 1974!) If humans weren’t designed to compensate and not be “perfectly” aligned, would a 123 lb human with scoliosis be able to deadlift 524.5 lbs?
Here are a few more statistics that make this “structuralism as the answer to our pain” more questionable:
- 96% of athletes younger than 22 will show changes on an MRI that some people call “abnormal.” But since everyone has them, how “abnormal” can they be? (Rajaswaran 2014)
- 37% of 20 year olds with no pain have disc degeneration in their spine (Brinjikji 2015)
- 57% of 20-50 year olds with no hip pain will have cartilage and ligament tears (Tresch 2016)
Structural problems aren’t the only pain-related theories I hear from patients. Many come in talking about “inflammation” or “tissue damage.” This can certainly be a contributing factor in pain, but it is generally not the only factor. And you don’t need to have damage to have chronic pain. Your nervous system can become sensitized. This sensitivity can come from a number of areas in your life. Depression, anxiety, fear of movement, a low sense of self control, the loss of meaningful activities…all are factors that might influence your sensitivity and chronic pain.
To understand injuries and pain problems and to recover from them more effectively, we need to stop thinking about the body as a machine that is inevitably going to break down and start thinking about the body as one big crazy system of neurology and biochemistry, and even crazier psychology and lifestyle factors. Throw in curve balls like poor dietary habits, medication side effects, exhaustion, emotional distress, smoking/pollutants, and being really out-of-shape or having inefficient biomechanics. These are more important indicators for pain than any “structural” issue. The body is strong and truly adaptable. You just need to give it the right stuff! Sleep, water, good nutritious food, movement, etc. All the things you know it really needs.
The bottom line is, pain is much more about sensitivity rather than injury. Any information that convinces your brain that you might need protection or that increases your danger alarm can contribute to your pain. We need to teach ourselves how to be more resilient to the external factors that are most of the time beyond our control.