Understanding and stopping chronic pain

Pain is like a danger alarm to the body. When we have fears and past trauma, the body will get triggered by these things and perceive them as pain to protect from danger.
It is a response to a threat - real or perceived.

When we are in pain, our first instinct is fear. We first wonder what’s wrong, and then how and if it can be resolved, and how long will it take.
The more answers we have to these questions, the less fear we have and the less pain we perceive.

The body does not actually have pain receptors, they have nociceptors which alerts the body to a stimulus so then the brain can determine whether this is dangerous enough to feel pain.

There are 3 different nociceptors in the peripheral nervous system:
Mechanoreceptors: responds to mechanical stimulus
Chemoreceptors: responds to chemicals
Thermoreceptors: responds to temperature

The lactic acid and build up of toxins in a trigger point cause pain from chemoreceptors (chemical response)
Whilst chronic pain takes less stimulants and nociceptors to feel pain.
Their action potential is lower, meaning sensations come quicker. (Action potential = point at which signal is sent to brain)

Places on the body are more sensitive if there is more danger, meaning even light touch can be painful.

Allodynia = when light touch is painful
Higher emotional state = reaching action potential is lower = more sensitive.

Sensory changes may be due to a lesion, compression and/or irritation of the sensory nerve anywhere from the nerve root to the terminal branches in the skin.
The good news is that sensors only live for a few days and are then replaced by fresh sensors. This means your sensitivity is constantly changing, depending on environment, psychological and social factors. (Butler & Moseley 2003, pg 31).
This allows us to change the sensitivity.

Different types of nerve fibres:
A-delta nociceptor fibres:
- First initial response
- Sends information quickly (gets to brain really fast)
- Sharp, pricking pain (e.g. Putting a needle into the skin) = A-delta
- Dermatome needling (tapped into the skin (epidermis))

C polymodal nociceptive fibres:
- Second response
- High threshold
- Activated by mechanical, thermal or chemical stimuli in deep skin layers, muscles, joints.
- Slower
- Trigger point pain (ache feeling)
- When needle goes in beyond being tapped into the skin

A-beta fibres:
- Sensitive to light touch (cotton ball) and proprioception
- Low threshold
- Mechanoreceptors in skin, muscle, tendons and joints
- Stops the ache feeling because it is covering a sensation with another one

For a message to get across, chemicals need to be correct in the dorsal root ganglion.
Electrical –> chemical –> electrical

Pain gets sent through by a nociceptor to the spinal cord, then to the brain to decide the danger level, to then see if there will be a pain response.
This information goes through the dorsal root ganglion (DRG) and dictates whether it goes through.

The brain can stop a message if something else is more important, meaning the body will know there’s pain but the message won’t get to the brain.

So how can we stop this loop cycle of chronic pain?

DERMATOME NEEDLING
Needle goes into the skin —> A-delta response
Message goes through DRG
Brain sends inhibitory signal down spine because foreign object/pain
Once needle is out —> pain still gets sent but is blocked in the DRG – therefore taking away pain

Injury + worry + pain = more excitatory chemicals = more pain = more worried
Then injury is repaired —> but still pain = nervous system

Dermatome dry needling helps to stop this feedback loop (chronic pain cycle)!

So where does the needle go? I hear you ask

We conduct dermatome testing to see which nerve fibre has lost sensitivity and where on the body.
The area on the skin that has a different sensitivity correlates with a spinal segment.
So, we place a needle in the area affected or the spinal segment that relates to that area.
I.e. ulnar nerve = C8 spinal segment – so you would place a needle besides this area if having trouble with the ulnar nerve

Evidence shows that knowing why we hurt will help us heal.
Figuring out what your fear is and creating a goal out of overcoming it, will result in happiness and less pain once you reach your goal.

To summarise, when you have an injury that makes you worried it increases the excitatory chemicals in your nervous system, even once it is repaired because the body sends signals to the brain that there is danger. (Central sensitization = when symptoms don’t match condition)

This means, the more worried you are, the more pain you feel.
Dermatome needling can stop this feedback loop by sending a signal to the brain and the brain will send back inhibitory chemicals to block pain.
Once you know you can do things you love, it will decrease your pain.

Happy = more inhibitory chemicals = less pain
More scared about pain = more pain

‘A lack of knowledge and understanding enhances fear’ (and, remember, fear enhances the likelihood of perceived pain). For example, when pain is unexplained or ongoing, or when it is deep and not visible, it seems more threatening and there is therefore a greater likelihood of increased pain perception. Conversely, ‘the more information that a patient has about a surgical procedure, even knowing that pain afterwards is quite normal, will reduce the amount of pain killers required after surgery’ (Butler & Moseley 2003, p.21)

References:
Butler, D & Moseley, L 2003 & 2011, Explain Pain, Noigroup Publications, Adelaide
Doidge, N 2010, The brain that changes itself, Scribe publications, Brunswick, Victoria
Josh Davies Pain Physiology
https://www.noigroup.com/scientific-evidence-behind-explain-pain-second-edition