by Jay McCallum, PT, DPT, OCS
This post has been a very long time in the incubator, partly because we’re all so busy and partly because we wanted to be able to give you both some science and some clinical reality. It started last October when Amy and Jay went to a conference in Portland on the topic of chronic pain. It was taught by a pair of amazing researchers, Paul Hodges and Lorimer Moseley. Paul and Lorimer are both physical therapists – ‘physiotherapists’, actually, given that they’re Australians – but they have devoted their professional lives to the study of how pain works and between them have published nearly 300 scholarly articles on the topic.
Because they covered so much ground this is going to be the first of a three part blog. I’ll talk about Paul’s work today, and then try to cram Lorimer’s material into a second blog, and finally talk about our experiences in the clinic working to implement their findings into actually treating patients.
How Does Chronic Pain Affect How We Move?
This is really what Paul Hodges’ work is about. He is best known in the world of physical therapy as the researcher who told us all that the transversus abdominus is important in stabilizing the spine, but that’s really not at all fair to the body of his work. What he has focused on is how the body solves the problem of keeping a stack of bones like the spine stiff enough that it doesn’t collapse, yet mobile enough to move. And, what he’s found is that people do it in lots of different ways (of course). There are, however, some patterns once you step back from the detailed specifics, and, more importantly, people who have a history of back pain tend to use a different set of strategies than people who don’t have back pain. Most of the research here is focused on back pain, but it’s quite likely that similar patterns are at work with other locations of chronic pain, like the neck.
Generally speaking, the muscles of the trunk can be divided into muscles that are closer to the spine and those that are further away, with of course some muscles situated in a bit of a gray zone in between. And Paul’s work suggests that the ‘normal’ way that we move is that the muscles that are closer to the spine activate to create just the right amount of stiffness to support the loads we put on our spines, while those further from the spine are primarily concerned with generating movement of the spine.
The best known of those deep, stabilizing muscles are the multifidus and the transversus abdominus, and the ones we tend to forget about are those that make up the pelvic floor. These muscles are relatively small, located right in there close to the spine, and are designed to stay ‘on’ for long periods of time at a relatively low intensity. They are also supposed to ‘pre-activate’, meaning that before you go to pick up that pencil on the floor the brain tightens them to stabilize the back.
What goes wrong?
We get stuck in a pattern. When a person first injures his or her back, the body’s reaction is to brace it – to tighten the bigger muscles that are further out from the spine and have longer lever arms to pull on it. Those muscles normally exist to generate movement, but get pressed into service to hold the injured spine in place. That pattern is supposed to quiet after a while, but if it doesn’t it can become the “new normal,” the primary strategy for keeping the spine stable. And that’s really a problem, because those muscles are NOT designed to be on for long periods of time, and so they complain about it, and get trigger points, and make the spine feel stiff all the time. And they use too much force, so the underlying joints have too much pressure on them. And they just aren’t very good at this new job, so people hurt their back picking up that innocent pencil because the nervous system didn’t stabilize the spine quite right (but they DON’T hurt their back lifting heavy things, because they consciously brace. Sound familiar?). And so, the classic pattern goes, people have further episodes of back pain and each one intensifies this pattern.
Hey! That’s me! What can I do??
And…there we have the problem. Obviously, what we’d LIKE to do is turn off those overactive superficial muscles and re-activate the deep ones. But, it isn’t quite so simple. These changes in muscle activation are accompanied by changes in brain structure. Put more simply, most people have had a LOT of practice at this pattern. We’ll talk about this more in my third post, but a couple of key points is that pain of this type is not just a ‘strengthening’ issue – it’s much more about coordination. And you have to work at it from a lot of angles, trying to both activate the deep ones (intentional exercise, practice, feedback) and quiet the overactive ones (stretching, motion, relaxation, massage and manual therapy). Most importantly, treatment needs to be individualized and very attentive to details, which is how we do things at CoreBalance Therapy.