Train the brain to remove back pain

We’ve all heard the expression “It’s all in your head.” In the case of chronic back pain, it may actually be true. But not in the way you think.

Pain researchers have long understood the connection between the brain and the body when it comes to chronic pain. This connection is particularly evident in chronic back pain which can persist for decades without a reliable physical explanation or cause. Indeed, it has been understood that people suffering from chronic pain have adaptations in their brain which can lead the pain to persist. For these people, their pain is unresponsive to drugs, surgery and exercise treatments because these interventions attempt to treat the pain where it is felt (the back) and not at its source (the brain).

A group of Australian researchers from two of SPHERE’s Partner Organisations: UNSW and Neuroscience Research Australia (NeuRA) have recently published the results of the RESOLVE trial in the August 2022 issue of JAMA. This trial shows that sensorimotor training not only decreases back pain for chronic pain sufferers but, in many cases, completely eliminates disability associated with the pain. RESOLVE paves the way for the new effective drug-free treatment for chronic pain to be available to patients across Australia as early as six to nine months from now.

And it all starts by training the brain.

The brain and chronic pain

RESOLVE trial leader, Professor James McAuley, Director, NeuRA’s Centre for Pain IMPACT (Investigating the Mechanisms of Pain to Advance Clinical Translation) and the School of Heath Science at UNSW, explains that the brains of people suffering from chronic back pain are different to people who don’t have pain.

“Information coming into the brain from the back is processed differently by people with chronic pain. We think this makes the brain oversensitive to perceived threats to the body.”

Professor McAuley, who is also a member of SPHERE’s Musculoskeletal Health Clinical Academic Group (MSK CAG) and Lead of the Low Back Pain Group, further explains there are both functional and structural differences in the brains of chronic back pain sufferers.

“In people with chronic back pain, our research showed that there is reduced volume of grey matter in the medial pre-frontal cortex and interior insular of the brain. These two areas are often associated with cognitive function and emotional processing and regulation.”

The other place where there are obvious differences is in the primary somatosensory cortex. An important function of the primary somatosensory cortex is its ability to locate where specific sensations arise in the body. For people who have had back pain for a long time, that ability becomes more diffuse.

The representation of the back has changed which means that the signals coming from the back may be represented inaccurately. Understanding this was the key to the

development of this new therapy.

“It has opened up a new way of managing pain. We realised that if information coming from the back to the brain is processed differently, we could develop some therapies to try to make that processing more precise.”

The RESOLVE trial

Understanding the critical role that the brain plays in chronic pain, researchers developed a graded somatosensory retraining program to train the mind and body together.

“People with back pain are often told their back is vulnerable and needs protecting. This changes how they interpret information from their back and how they move their back. Over time, the back becomes less fit, and the way the back and brain communicate is disrupted in ways that seem to reinforce the notion that the back is vulnerable and needs protecting. The treatment we devised aims to break this self-sustaining cycle,” Professor McAuley explains.

The treatment had three goals. The first was to align patient understanding with the latest scientific evidence about what causes back pain. The second was to normalise the way the back and the brain communicate with each other, and the third was to gradually retrain the body and the brain back to a normal protection setting and resumption of usual activities.

The study divided 276 participants from South Eastern Sydney and South Western Sydney Local Health Districts into two groups. Over 12 weeks one group undertook graded sensorimotor retraining and the other sham treatments designed to control for placebo effects, which are common in low back pain trials

A photo of the patient’s back is provided to help with training

The first group: retraining

After the first step of the trial, which aimed to improve patients’ understanding of the way the brain processes pain, patients underwent retraining sessions with the aim to reconnect the brain and the back.

When touched on the back, people with chronic pain have difficulty pinpointing the intensity and exact location of where they are being touched. This lack of tactile acuity was the focus of the training which involved gently touching a person’s back with a pair of calipers and then have them guess where the sensation was felt by one point or two. To help them do this, patients held a photograph of their backs which were marked with small dots.

In addition to locating where the touch was coming from, patients were touched with either the pointy or blunt end of the calipers and asked to identify whether the touch felt smooth or sharp.

Professor McAuley explained that as a patient’s tactile acuity improved, they became less uncertain about the information being processed from the back to the brain.

Patients were then asked to look at photographs and videos of people moving their backs and then to imagine themselves doing the movements.

In the third and final step of the training, patients were taught to experience movement of their backs without pain. This included mastering precise movements of the lumbar spine, thoracic spine and hips. Then, using the skills learnt from these movements, patients progressed to practising components of functional tasks they had previously identified as being problematic. Finally, participants practised functional movements relevant to their values and goals.

The second group: sham treatments

Bias was reduced in the trial by the inclusion of a placebo (control) group, who for 12 weeks, received weekly sham treatments including brain stimulation and low intensity laser therapy from machines that were not actually switched on.

“This is the first treatment of its kind for back pain that has been tested against a placebo.”

As a three-stage program, the treatment aims to change the way that people think about their body pain, how they process sensations from their back and how they move their back during activities.

The results

The results of the trial showed a clinically meaningful effect on pain intensity and disability.

For the participants of the graded sensorimotor retraining program, pain levels dropped from 5.6 at the commencement of training to an average of 3.1 (on a scale from zero to 10) at 18 weeks post randomisation. This was compared to the control group who experienced a drop from 5.8 to four.

“While we know that the role of the brain in pain can mean that even a placebo can make people feel better which did happen in this trial, our sensorimotor training program provided additional benefit beyond that of the placebo.

“People who received the training were happier, reported their backs felt better and their quality of life was improved. It also looks like these effects were sustained over the longterm; twice as many people were completely recovered and there was a clinically meaningful difference in disability that was sustained over one year.

“Very few treatments for low back pain show such long-term benefits,” said Professor McAuley.

Where to now?

The most exciting result of the study is that the treatment can be easily translated into clinics for patients to access. A training package for physiotherapists, exercise physiologists and other clinicians is currently in

Professor James McAuley

development so that the treatment should be available for patients to access at a similar cost to other therapies, potentially as early as the next six to nine months.