Body Intelligence: 5 Ways Our Bodies Protect Us from Pain
For the past few years, my studies in pelvic health have taken me further and further outside of the pelvis. I have learned and continue to learn how amazingly interconnected our bodies actually are. The pelvis can be influenced by the ankle, the knees, and even the neck! It is amazing and awe-inspiring.
Identifying Dysfunctional Movement Patterns
Recently, my studies took me to the Level 1 Selective Functional Movement Assessment (SFMA), where I spent two days learning a systematic way to evaluate movement and identify where dysfunctional patterns exist, from head to toe! There are many different systems and programs out there for evaluating someone’s movement, and honestly, I don’t think one is superior to the other. I liked this one though, as it made sense to me and the initial screen could be completed in two minutes.
Why is it important to look globally at human movement when a person is experiencing pain anywhere in the body? As I mentioned above, there are lots of reasons. We now know that movement patterns change when a person is experiencing pain. These shifts are initially helpful and important—your brain wants to protect you from experiencing harm. However, dysfunctional movement patterns, although helpful to the body in that moment, can persist and lead to further problems down the road.
Paul Hodges and Kylie Tucker examined the current theories regarding movement adaptations to pain in a 2011 review published in the International Association for the Study of Pain. They looked at the current research regarding movement variations in pain, and frankly poked holes in the theories where holes needed poking. They then presented a new theory on the motor adaptations to pain.
New Theory on Motor Adaptations to Pain
The theory they presented is based on the premise that movement adaptations occur to reduce pain and protect the painful part. The way in which a person does this actually varies and is flexible. Here are the basics of their theory, simplified, of course. I do encourage you to read the paper if you’re interested—it’s great!
Adaptation to pain involves redistribution of activity within and between muscles. Basically, the brain varies which pools of motoneurons fire in a muscle based on the individual and the task requirement. The common goal is to protect the painful part from pain or injury, but the way the body does this can vary greatly. We know that the motoneurons that are active before and during pain tend to reduce activity, and the production of force actually seems to be maintained by a new population of units who were previously inactive. Normally, motoneuron units are recruited from smaller to larger pools to allow for a gradual increase in force. But during pain, a person often will have earlier recruitment of larger pools to basically allow for a faster development of force to get away from pain (think fight-or-flight response!). Also, the new population of active units may be altered to change the direction of the force generated by the muscle, again, aiming to help protect the painful structure. We also can see in some areas, like the trunk, that one muscle, such as the transverse abdominis, may become inhibited, while other larger muscles become more activated. This again makes sense with the body’s goal of protection. Quick activation of larger motor units allows for a quick activation of a muscle to help protect and escape pain.
Adaptation to pain changes mechanical behavior. Basically, as we just discussed, the redistribution of activity within and between muscles changes the force and output of the muscle. Hodges & Tucker give us a few examples of this. First, they’ve found that when someone has knee pain, the quadriceps muscles fire differently to change the direction of knee extension by a few degrees. They also explain that the changes in muscle firing in the trunk muscles in someone with back pain leads to more stiffness, less control of movements and less anticipatory action. Basically, in each of these cases, the big picture motion stays the same, but there are small changes in how the body accomplishes those tasks.
Adaptation to pain leads to protection from pain or injury, or threatened pain or injury. Basically, this redistribution of muscle firing is done to protect against pain—or even the threat of pain. When a person experiences pain, the brain chooses a new movement pattern in order to splint the injured area, reduce the movement of the area, or alter the force on the area. The interesting piece here is that the body responds this way even when there is a perceived threat of pain. The key with all of this is that the adaptation varies significantly. No one pattern is seen for all types of pain, but the nervous system has a variety of options for protection.
Adaptation to pain involves changes at multiple levels of the motor system. So, although we know that the activation of motoneuron pools can change during pain, this alone does not describe the variability we see. We know now that the way the body changes movement can be influenced by structures in the brain, spinal cord or at the local level of the motoneuron. All of this is going to be influenced by the task at hand and the individual—thoughts about the pain, emotions, stressors, and previous experiences.
Adaptation to pain has a short-term benefit, but with potential long-term consequences. Although the short-term benefit is the protection of the painful area and prevention of further pain, this may lead to consequences down the road if the adaptation persists. Of course, we assume in this case that movement in a non-pain state is likely the most efficient and optimal way to move. So changes over time could produce decreased movement variability, modified joint loading, modifications in walking patterns, and ligamentous stress. Hodges and Tucker state that in order for these long-term consequences to occur, there would likely need to be a gradual maintaining of the compensation, so that the nervous system did not recognize it as being problematic. Basically, the brain slowly adapts to the new pattern and does not recognize the problems it could cause down the road.
The tricky thing is, we don’t really know for certain how these long-term changes can impact the body, but we do know that one of the biggest risks for injury is previous injury. This is also true in yoga. I can’t help but think that movement changes could possibly contribute. But how do we change this in a positive way? The first step is to understand pain —to learn what pain is and to develop a healthy mindset toward pain. We also have to look closely at our own emotions, our psychological state, and our previous experiences, and to understand how all of these things can influence how our brain chooses to respond to pain. But we also need to identify which movements the body has changed, understand how the brain is varying movements to protect against pain, and then slowly provide variability with good force modulation in those movements to help the brain learn optimal, safe and pain-free ways to move again.
You may also want to read this article on the origin of pain from YogaUOnline and Olga Kabel – When You Are Hurt Where Does Pain Come From?
The relationship between pain and movement are also explored in this course from YogaUOnline and Anita Boser – Youthful Spine, Youthful Body, The Role of Fluidity in Healthy Aging.
Reprinted with permission from Jessica Reale, PT.
Jessica Reale, PT, DPT, WCS is a board-certified specialist in Women’s Health and treats pelvic floor disorders in men, women and children at One on One Therapy in Atlanta, GA. She received her doctorate in physical therapy (DPT) at Duke University School of Medicine and was the director of the largest pelvic floor rehabilitation program in South Carolina prior to relocating to Atlanta in 2015. Jessica is passionate about helping her patients achieve optimal health through individualized treatment plans integrating the most current research. She is actively involved in educating the community and other professionals and has lectured at support groups, conferences, and universities. Jessica writes regularly about all issues related to pelvic health at her blog, www.jessicarealept.com