Fibromyalgia and centralization of pain, what does this mean? I wanted to know specifics and I got answers from Dr. Karl Hurst-Wicker, pain specialist.
Hippocampus and Fibromyalgia, What? That’s the Million-Dollar Question
"Fibromyalgia patients have reduced hippocampal volume compared with healthy controls." What does this recent study mean?
Dr. Hurst-Wicker explained it this way. In this study, researchers used MRI imaging to look at the brains of both healthy people and those with fibromyalgia. We have a greater understanding of changes that occur to the body because of fibromyalgia, and we have a better understanding of neurologic mechanisms that contribute to fibromyalgia symptoms. What these researchers found was on average people with fibromyalgia have a region of their brain, the hippocampus, that is slightly smaller than people of the same age and gender who did not have fibromyalgia.
This region is deep in the brain, near where the spinal cord and brain meet and is involved in the formation of memories and navigation. Because patients suffer from “fibro brain” (i.e. memory and cognitive difficulties), there is an interest in learning more about the hippocampus and its relationship. It may indicate either a cause, or an effect of that condition.
One of the cons of brain imaging studies is that while they show us there is a difference, they don’t give us an answer to the chicken or egg question. To put it in perspective, in London the cab drivers have to take a hard test proving they have a detailed and intricate knowledge of how to get from point A to point B. When they use an MRI to look at the hippocampus of “London cab drivers,” they found that their hippocampi (plural) were bigger than the average person who wasn’t a cab driver. The question then becomes is the hippocampus larger because the cab drivers studied so hard to pass that test? Or, did the people who became cab drivers manage to do so because they were born with an unusually large hippocampus? The same holds true for this study, is having a smaller than usual hippocampus a cause of fibromyalgia? Or, is the fibromyalgia causing the hippocampus to shrink? That’s the million-dollar question.
Fibromyalgia and Myofascial Pain: Peripheral to Central and Central to Peripheral
According to Dr. Hurst-Wicker, chronic pain from myofascial pain syndrome (MPS) is a common cause of chronic pain. In fact, one study showed that it constituted 30% of the pain complaints in a primary care/internal medicine practice. Myofascial pain syndrome can be the primary pain generator, and at the same time, MPS may flare up or indicate some other pain generator in the same area. That’s why a big part of evaluating a patient with pain is getting a good history and physical exam to determine if they have only MPS, or if they have MPS and some other concurrent problem.
There is a good deal of overlapping between MPS and fibromyalgia syndrome(FMS). Likely this is related to the consistent long-term activation of peripheral pain pathways causing central sensitization and other changes in the nervous system that contribute to the development of FMS. Conversely, it can work in the other direction too, a patient with a primary FMS can develop MPS, in no small part because the FMS can amplify and perseverate even minor myofascial pain and injury to the point where it can propagate and become a regional issue.
All pain has an affect and is effected by our brain. Chronic pain can cause our brain to change physically on a cellular and molecular level. At the same time, our brain can behave unusually, such as central sensitization making pain worse. We can use our brains to meditate, deep breathe, etc. to reduce the pain we are experiencing. In the end, our head is a critical piece of the whole pain equation.