PT Classroom - The Neuromatrix Model of Pain and Treating With Pain Education ׀ by  Bill Lyon, PT, DPT, CSCS

Even though it’s been almost 15 years since Dr. Melzack developed the Neuromatrix theory of pain, a good amount of clinicians still focus treatment of chronic pain with a very patho-mechanical approach to chronic pain treatment. Many patients can get a bad taste in their mouth when it comes to PT when they are pushed through stretches and exercises that they feel can be harmful to their wellbeing and will cause them pain. As a growing field of evidence based practitioners, physical therapy needs to move beyond this. Thankfully the neuromatrix model of pain and researchers that have utilized its concepts have given us ways to do so.

For those who may not know, the neuromatrix model of pain portrays the complicated intertwining of different areas of our nervous system, mind, and body and the influence this has on pain and pain perception. Its development was brought about during the research of phantom limb pain in patients with amputation that couldn’t be explained by pathomechnical models. The inputs into the nueromatrix include Cognitive (memories of past experience, attention, anxiety, depression), Sensory (cutaneous input, visceral input, visual, musculoskeletal), and Motivational-affective (limbic system, associated homeostasis/stress mechanisms). The important broad message of this is that pain is not purely a sensory, musculoskeletal input. It is interpreted by the brain and therefore the affective and cognitive inputs can have a very dramatic input. Any clinician who has treated patients with chronic pain has likely treated someone with anxiety, depression, PTSD and the like with chronic, global pain that doesn’t “make sense” by a pure musculoskeletal explanation, or may be ongoing years after an injury should have been healed by the body. This is a great example of the different inputs effects on what our CNS interprets as pain.

The importance of the neuromatrix and understanding the different inputs and their influence on a patient’s pain is that we generally need to treat more than muscles and joints to help these patients on a path to healing. Much research has been done to show the effect on pain education on patients’ pain levels. In a systematic review of 6 studies published December 2011, Louw, et al. found that Neurocience education had significant positive influences on both pain levels and function/disability. Additionally, another article by Louw and Puentedura found that educational sessions on pain science helped to change patients’ conception of the role of physical therapy in treating chronic pain and shift it to a more positive view. As a clinician and neuro-musculoskeletal expert, it is the physical therapist’s job to explain the way our brain influences and perceives pain and injury, the effect of peripheral and central sensitization of pain, and ways we can change the neurophysiology to work in our favor. Patient education should be done in easy to understand terms, often using analogies and metaphors in a low educational level. The gathered evidence shows that the more the patient understands about their pain and what is happening in their body, the more positive the effect.

Educating a patient on pain, neurophysiology and neurobiology in easy to understand ways is an effective tool for decreasing the negative inputs into the neuromatrix, resulting into a positive shift in pain perception. Getting patients to understand that pain is not just an injury, or threat of injury, to tissue, but also is associated with nervous system sensitivities, past experiences, and psychosocial differences will compliment exercise and manual therapy approaches to pain treatment. Additional resources, as well as educational tools, can be found through the Neuro Orthopaedic Institute (http://www.noigroup.com/en/Home), and The International Spine and Pain Institute (https://www.ispinstitute.com), two excellent organizations that I am not affiliated with.
 

Last revised: April 22, 2015
by Bill Lyon, PT, DPT, CSCS, USAW-L1