Types of pain – Nociceptive pain

(The following is the transcript for the video above)

In the introduction video I mentioned that pain that you're experiencing does NOT have to equate to physical injuries or deformities. But often it DOES as well. The thing is, that there are different TYPES of pain and identifying which one or ones you're most likely to be experiencing, is absolutely crucial to the management of your pain.

According to Prof Clifford Woolf of Harvard Medical School, there are four types of pain (1,2): Nociceptive, Inflammatory, Neuropathic and Dysfunctional. These are NOT mutually exclusive groups, but can and often occur simultaneously, and all equally important. Let's look at Nociceptive pain for this video.

There are different types of nerves in our body, responsible for different sensations. For example, there is one for pressure and stretch, called mechanoreceptors, one for temperature called thermoreceptors, and one for pain, called nociceptors. Actually in fact, nociceptors are often thermoreceptors as well.

Nociceptive pain is when these nociceptors are stimulated, and activated. Here is my finger. If I bend it, the mechanoreceptors around the joint tells my brain that my finger is being stretched. But it's not painful, yet. If I stretch it more, then the stimulation is large enough to break the threshold of activation of the nociceptors.

So when the nociceptors get stimulated, just like all nerves, they generate electrical signal called Action Potential that gets relayed into the spinal cord, and into the brain. You still will NOT feel any pain however. You'll only feel pain, when your brain, consciously or unconsciously, decides that the signal is important enough for it to be noticed.

This kind of pain, or Nociceptive pain, is the "typical" pain most of us know and understand. Like a joint sprain, a smack on your shoulder, or sudden change in temperature. This sort of pain is important, because it is a warning of a potential threat to our body (3), and absolutely vital for our survival.

References

1. Vardeh D, Mannion RJ, Woolf CJ. Toward a Mechanism-Based Approach to Pain Diagnosis. J Pain. 2016;17(9 Suppl):T50-69.

2. Woolf CJ. Pain: Moving from Symptom Control toward Mechanism-Specific Pharmacologic Management. Annals of Internal Medicine. 2004;140:441-51.

3. Melzack R, Katz J. Pain. Wiley Interdiscip Rev Cogn Sci. 2013;4(1):1-15.

Pain and injury – they’re NOT same

It's easy to think that pain are injury are same. They indeed are often (but not always) related but it's crucial to know the difference and how such knowledge can impact rehabilitation.

(The below is the transcript of the video above)

If you are reading this chances are you might have been having some sort of chronic pain condition. Such as spinal pain, fibromyalgia, complex regional pain, arthritis, headache, abdominal or pelvic pain.

Dealing with such pain requires an approach that is quite different from what's needed for majority of health conditions from both the clinician and patients.

So what IS the approach?

First of all it is massively important to recognise a fairly universal belief that injury equals pain (1).

Now that sounds pretty reasonable doesn't it? You get a cut on your finger, it hurts. You break a bone, it hurts. You get a cyst somewhere in your body, it probably hurts.
It is fairly safe to believe that injury results in pain.

So it is naturally easy to believe the reverse: that having pain must mean that you have a physical injury. However that is a fallacy. The conditions that I had listed just before - fibromyalgia, complex regional pain, headache, some abdominal and pelvic pain, and even some good proportion of arthritis - have no relationship with existence of physical injury (2-5).

That's because that you experiencing pain has more to do with the behaviour of your nerves, which is NOT always dependent on whether you have an injury or not. And the behaviour of the nerves CANNOT BE SEEN.

So the fact you have pain right now, especially if chronic, may have very little to do with whether you have had or currently have a physical injury. In fact the initial argument, that injury results in pain, is not always correct either.

What I'm saying is, if you want to take control of your chronic pain, you need to be open to the very possibility that the idea of "injury equals pain" or "pain equals injury", is quite unlikely to apply to you, and your experience of pain has more to do with the factors that are different in nature than physical injuries.

Then what ARE those factors causing your pain? That's for another day. The body is wonderfully complicated and there are so many reasons why you could be experiencing pain. We'll go through these one by one in our future videos.

But NOTHING will work unless you are at least open to the idea that your pain may have little to do with physical injuries and instead more to do with other less visible factors but just as physiologically real.

References

1. Courtney CA, Fernandez-de-Las-Penas C, Bond S. Mechanisms of chronic pain - key considerations for appropriate physical therapy management. Journal of Manual & Manipulative Therapy. 2017;25(3):118-27.

2. Chandnani V, Ho C, Gerharter J, Neumann C, Kursunoglu-Brahme S, Sartoris DJ, et al. MR FINDINGS IN ASYMPTOMATIC SHOULDERS: A BLIND ANALYSIS USING SYMPTOMATIC SHOULDERS AS CONTROLS. Clinical Imaging. 1992;16:25-30.

3. Connor PM, Banks DM, Tyson AB, Coumas JS, D'Alessandro F. Magnetic Resonance Imaging of the Asymptomatic Shoulder of Overhead Athletes. A 5-Year Follow-up Study. The American Journal of Sports Medicine. 2003;31(5):724-7.

4. Panagopoulos J, Hush J, Steffens D, Hancock MJ. Do MRI Findings Change Over a Period of Up to 1 Year in Patients With Low Back Pain and/or Sciatica?: A Systematic Review. Spine (Phila Pa 1976). 2017;42(7):504-12.

5. Rudy IS, Poulos A, Owen L, Batters A, Kieliszek K, Willox J, et al. The correlation of radiographic findings and patient symptomatology in cervical degenerative joint disease: a cross-sectional study. Chiropr Man Therap. 2015;23:9.

Please click here for the next video/post, beginning with discussion on types of pain.