Cortical Changes with Back Pain

If you work with orthopedic patients, I am sure that you have had a back-pain patient that you have discharged, only for them to return a year later suffering from another episode of pain. We all know that once someone suffers from a back injury, they are more likely to develop a chronic issue. Even patients with insidious back pain and no specific injury often develop chronic issues and can have pain that waxes and wanes after the initial episode.

What happens in the body to cause this? Most of us have learned that the pelvic floor, transverse abdominus, and the deep fibers of the lumbar multifidus play an important role in stabilization. With injury, these muscles can become less effective in stabilizing the spine and pelvis. Studies have shown that muscle atrophy in the lumbar multifidus has been shown to occur with injuries and persist after resolution of the pain.¹

I recently did additional research to find out other reasons that cause these local stabilizing muscles to not function optimally. I found that these muscles also can suffer from arthrogenic muscle inhibition after an episode of low back pain.² Arthogenic inhibition is a deficit in neural activation to a muscle. It is thought to occur due to a change in the discharge of articular sensory receptors due to swelling, inflammation, joint laxity, and damage to afferent nerves.² EMG studies have shown reduced neural activity in the deeper fibers of the multifidus in patients with back pain.³

Another thing that fascinated me was that cortical changes in the brain also occur with low back pain. Changes in cortical representation of the multifidus and the body’s ability to voluntarily activate the muscle has been noted.⁴ Motor retraining has been shown to reorganize the motor cortex with regards to the transverse abdominus.⁵ Also, improvement in brain organization and function occurs after resolution of back pain.⁶

This is good news for patients! As therapists, we may not be able to do anything with respects to arthogenic inhibition. However, we can work on motor retraining for the core muscles. It has been shown that specific training that targets the multifidus can restore the neural activity to the multifidus and lead to improvement of pain and function.^7,8 Training the multifidus can be difficult for therapists to teach. However, studies have found that ultrasound guided biofeedback is helpful for patients to learn to contract their multifidus.^9,10

Come learn more about the multifidus and how it relates to back pain and stability. In Rehabilitative Ultrasound Imaging: Women's Health and Orthopedic Topics we will go over how to help your patients learn to activate and strengthen their multifidus. Join me on February 28 - March 1st in Raleigh, NC to learn new ways to help your patients!

1. Hides JA, Richardson CA, Jull GA. Multifidus muscle recovery is not automatic after resolution of acute, first‐episode low back pain. Spine 1996;21:2763–2769.
2. Russo M, Deckers K, Eldabe S, et al. Muscle control and non-specific chronic low back pain. Neuromodulation: Technology at the neural interface. 2018; 21 (1): 1-9.
3. D'Hooge R, Hodges P, Tsao H, Hall L, Macdonald D, Danneels L. Altered trunk muscle coordination during rapid trunk flexion in people in remission of recurrent low back pain. J Electromyogr Kinesiol 2013;23:173–181
4. Massé‐Alarie H, Beaulieu L‐D, Preuss R, Schneider C. Corticomotor control of lumbar multifidus muscles is impaired in chronic low back pain: concurrent evidence from ultrasound imaging and double‐pulse transcranial magnetic stimulation. Exp Brain Res 2015; 234:1033–1045.
5. Tsao H, Galea MP, Hodges PW. Driving plasticity in the motor cortex in recurrent low back pain. Eur J Pain 2010;14:832–839.
6. Seminowicz DA, Wideman TH, Naso L et al. Effective treatment of chronic low back pain in humans reverses abnormal brain anatomy and function. J Neurosci 2011;31:7540–7550
7. França FR, Burke TN, Caffaro RR, Ramos LA, Marques AP. Effects of muscular stretching and segmental stabilization on functional disability and pain in patients with chronic low back pain: a randomized, controlled trial. J Manipulative Physiol Ther 2012;35:279–285.
8. Goldby LJ, Moore AP, Doust J, Trew ME. A randomized controlled trial investigating the efficiency of musculoskeletal physiotherapy on chronic low back disorder. Spine. 2006;31:1083–1093.
9. Ghamkhar L, Emami M, Mohseni‐Bandpei MA, Behtash H. Application of rehabilitative ultrasound in the assessment of low back pain: a literature review. J Bodyw Mov Ther 2011;15:465–477.
10. Van K, Hides JA, Richardson CA. The use of real‐time ultrasound imaging for biofeedback of lumbar multifidus muscle contraction in healthy subjects. J Orthop Sports Phys Ther 2006;36:920–925