Dr Ashley Francis is a Clinical Psychologist with an interest and expertise in working with people experiencing chronic pain, medically unexplained symptoms and psychological trauma.In this three part blog, Dr Francis discusses the latest neuroscience research which shows that pain is a protective response of the brain to perceived danger, and factors such as emotions when perceived by the brain as dangerous, can activate pain neural pathways even without tissue damage to the body.
The views he expresses in this blog are his own based on clinical experience, training and
research.
Part 1: Causes, controversies and current views on chronic pain
The suffering of chronic pain
Chronic pain, defined as pain that lasts more than three months, is reported to affect between one-third and one-half of the UK population (Fayaz et al., 2017). Chronic low back pain itself is the leading cause of disability in the UK. The physical and emotional strain on sufferers is huge, as too is the financial strain on the UK economy: more money is spent on chronic pain than diabetes, cancer and cardiovascular disease combined; put differently, chronic pain expenditure is greater than the savings the UK was proposed to make each year by leaving the European Union! Given this incredible burden it begs some fundamental questions - what causes chronic back pain and what can be done to treat it?
The issue of effective treatments for chronic low back pain has recently gained much
coverage in the British media (see http://www.bbc.co.uk/news/health-43469300 ) following a publication by pain experts criticising the poor outcomes and serious side effects of medical interventions such as spinal surgery and opioid-based medications.
In this publication, the experts recommend introducing less invasive first line treatments for low back pain, including physiotherapy and talking therapies, and stopping the routine use of MRI scans. As I will show, these medical interventions and scans are likely limited in their effectiveness and utility precisely because they proceed from a false assumption: that chronic back pain is largely caused by structural damage to tissues in the body.
The myth about spinal damage and chronic low back pain
When consulting a doctor with back pain that has persisted for longer than three months,
people are sent routinely sent for detailed physical investigations. Often this includes an MRI scan to identify any disease such as cancer, which may explain their on-going pain. In the absence of disease however, medical professionals point to the presence of structural damage to the spine as the cause of back pain. Patients are routinely told that their MRI scan has revealed some kind of bulge, protrusion or herniation of their spinal discs - these are spongy like structures cushioning the spine like shock absorbers in a car. “Your back is crumbling”, “thank god you can still walk”, and “if you don’t have surgery you will be in a wheelchair within the next year” are just some things I and other clinicians have heard from patient’s receiving the news about their spinal damage. The treatment recommended by surgeons in these cases is immediate back surgery.
If this is what you have been told about what is causing your chronic back pain however, then I am afraid you may have been misinformed. But don’t take my word for it; let’s look at the research! Many studies have replicated the now well established finding that damage or changes to discs in the spine is observed in the majority of healthy adults who don’t experience any pain whatsoever (see Borenstein, 2001; Jensen, 1994; Matsumoto, 2013). What is more, not all patients with chronic back pain are found to have problems with their discs. Some have referred to the wear and tear of discs as the ‘grey hairs of the spine’: in other words, it is a normal and harmless process associated with ageing. As Dr John Sarno, a Professor of Rehabilitation Medicine and a world leading expert in the treatment of chronic pain so aptly puts it, “these ‘abnormal’ MRI findings are ‘normal abnormals’”.
The poor evidence for medical treatments of chronic back pain
So it seems that structural abnormalities of the spine cannot account for chronic pain in a way that they can for acute pain. What is more, medical professionals ironically risk worsening patient’s pain by creating fear and anxiety (see Vlaeyen & Linton, 2000 for a review) when informing them of their ‘crumbling’ spines. These explanations of pain also necessitate costly and painful surgeries as well as other medical treatments such as opiate-based medications which have been found to have poor outcomes and can lead to problematic side effects and addiction (see Foster et al., 2018 for a review). Astoundingly, research shows that there is no difference between back surgery and non-invasive treatment methods, such as exercise or conservative therapies, in terms of pain relief (Gugliotta et al., 2016). Studies have also found little difference between steroid and placebo spinal injections, and where steroid injections do show a positive effect on pain, they are short-term and limited to specific back pain problems (Benoist, Boulu & Hayem, 2016). So if structural changes in the spine cannot explain chronic back pain then what other explanations are there? To answer this we need to consider the central nervous system and the role of the brain in creating pain.
The ‘reign of pain lies mostly in the brain’
All pain is ‘created’ in the brain. I want to distinguish between the ‘brain’ and the ‘mind’ here, as what is being discussed is the organ of the body and not the philosophical concept of the mind. Why do I make this distinction? Because I do not wish to mislead readers into thinking that I am saying that pain is made up (as often is a worry when patients with pain are sent to see a Clinical Psychologist like me). On the contrary, the pain is very real.
This is so important that it is worth repeating again - the pain is real! But damage to the tissues of the body or spine does not create pain in and of itself. All pain, even when there is tissue damage is created in the brain. To understand this fundamental idea let’s look at a common example in acute pain of cutting your finger on a kitchen knife.
When you cut your finger, the damaged tissue activates nerves sending a ‘danger signal’ into your spine and then up into the brain. The brain’s job is to decide whether this signal from your finger is a signifies you are in danger and therefore in need of protection. The brain makes this decision about safety not only based on this danger signal from damaged tissues, but also on other ‘cues’ such as your expectations of pain, your past history of pain in these types of experiences, how you are feeling emotionally in the moment, what thoughts you are having etc. In other words, it is not just about the danger signal from damaged tissue when it comes to pain but a number of factors. Ultimately, if the brain determines that on the balance of things you are in danger, even if there is no tissue damage , it will send another signal back down the spine and into your finger where you will feel pain and hopefully will stop using the knife and rest your finger so it can recover!
In the next blog Dr Francis considers in greater detail why the brain creates pain, how this is an adaptive response in acute pain but less so in chronic pain, and how emotions may come to signal danger and trigger ‘pain neural pathways’ in the brains of people exposed to adverse childhood experiences.