Understanding pain systems
Persistent pain is a “tricky” condition to explain to anyone. There are many, many changes in the pain nerve systems (neural processing systems) and their function in persistent pain. These changes include:
Nocioceptors receptors, like touch, pressure in skin, muscles, joints and other areas become more sensitive in persistent pain. More nerve messages are created and these “danger or threat” messages are repeatedly sent to the spinal cord and the brain. The brain assesses the level of danger from these messages to decide if the pain/s needs attention and protective action. The brain becomes over reactive to these incoming nerve messages, perceiving more danger or threat is occurring that is actually the case, a sensitisation process.
Damaged myelinated nerves, for example in nerve root compression due to spinal disc protrusion, are more excitable. The nerve fibres where the myelin is damaged communicate as they are now in direct physical contact with each other. This is called “cross talk” and is similar to exposed electrical wires shorting across contact points with each other. This explains the electric shock type pains that people with neuropathic pain describe.
“Windup” process in the spinal cord dorsal horn area multiplies the number of incoming messages from the sensors before they are transmitted to different brain areas for processing, interpretation and responses by the brain.
Loss of synchronisation of neural processing within the brain centres nerve networks to handle increasing multiple messages efficiently. There too many incoming messages for the brain’s processing systems to manage effectively. Added to this is a reduction of the brain’s ability to switch down incoming messages from the spinal cord neural pathways. This is called descending spinal nerve inhibition begins to fail to control pain experienced.
How to respond to patients who want to know: ‘what is persistent pain?’
Here are some useful tips on how to get some of the key aspects of persistent pain across to patients:
Use of metaphor
Using metaphors helps.
One commonly used metaphor that can be helpful is that of a faulty burglar alarm.
The alarm is being triggered as if a burglar is actually getting into the house – but in reality its sensitive sensors are picking up the slight movement of many other things within or outside the house. So a series of false alarms and no actual harm or burglary is occurring. It is difficult to turn the sensitivity of the sensors down and the alarm off altogether.
A car alarm is another variation on the alarm metaphor: we have all heard car alarms being triggered when a car is not actually being stolen.
Here Dr Tim Williams describes how he uses metaphor to help explain persistent pain to his patients:
Video duration: 40 seconds
This is ‘tip 5′ of Dr Tim Williams’ Ten Top Tips for GPs Towards Self-management of Persistent Pain – watch all ten top tips here.
Explaining Pain leaflet
The Explaining Pain leaflet is a good resource to share with patients to help them understand why pain persists. You can download it here to print off for your patient, or send them a link to it, via email.
Understanding Pain in 5 Minutes – video
Another really useful resource is the video ‘Understanding Pain in less than 5 minutes, and what to do about it!’
It has very simple messages about how pain works, and what the person can do about it themselves. It has a real self management focus message.
View it here – and again you can send the patient a link via email, so they can watch it themselves in their own time.
This Clinician Resource was revised in January 2018.
The Pain Cycle
A worksheet you can use with your patients to introduce the metaphor of a Pain Cycle to help explain how pain is impacting on their lives. Download the Pain Cycle >
While you’re here…
Live Well with Pain is a free resource, developed by clinicians who have given their time and expertise freely to support best practice in pain self management.
Maintaining and developing the website takes time and money. If everyone who finds it useful helps to support it, the future for Live Well with Pain will be secure.
Donating only takes a moment, and even a small amount will help ensure Live Well with Pain continues to develop as a valued, free source of knowledge, skills and tools by and for clinicians working with persistent pain.