The important characteristics of fibromyalgia are that this is a multifactorial pain disorder with very few physical findings. The old criteria for fibromyalgia included tender points, which was a physical finding. Fibromyalgia has become a disorder of self-report compared to a disorder associated with objective findings, which makes it challenging for providers to separate individuals with fibromyalgia from disorders that are associated with muscle disease, joint disease, neurological disease, and so on. The overwhelming evidence shows that the tissue of origin for nociceptive signaling in fibromyalgia, and probably in most musculoskeletal pain disorders, is the deep tissue, and our focus and the focus of many other groups has been muscles. It appears that muscles have the capacity to sense pain, and the transmission of signals to the spinal cord as well as the brain then is important. It also suggests that the disruption or even obliteration of this pathway is a potential treatment strategy.
Thus far, the really validated treatment strategies in fibromyalgia have been non-pharmacological therapies, including physical therapy, which has the strongest evidence for efficacy, as well as cognitive behavioral therapies and behavioral modifications in general. The effectiveness of pharmacological therapies in large population studies have not been very impressive; however, there are patient groups who respond, and one of the targets of current research is to identify the phenotypes that are associated with treatment response and then focus on particular treatments towards the specific and personal patterns that these patients have. There’s also good reason to believe that we are making progress in identifying the central nervous system mechanisms—we have worked on the spinal cord mechanism for the last decade at least—and if any of these mechanisms can be modified either with pharmacological or non-pharmacological therapies, this would definitely improve the pain and suffering of these individuals, hopefully to a large degree.