Understanding Trigger Points

The American Fibromyalgia Syndrome Association (AFSA) has lent its support to three important projects that may further our understanding of fibromyalgia pain symptoms. Two studies funded by AFSA concentrate on the role of myofascial trigger points in generating fibromyalgia symptoms. The third study funded by AFSA focuses on how the premature loss of gray matter in fibromyalgia patients contributes to pain and fatigue, and how it also affects their cognitive and physical function.

Leading experts in the field feel that the role of myofascial trigger points is an area of research that has been all but ignored. Fibromyalgia specialists believe that gaining an understanding of how these trigger points work may change the diagnostic criteria for diagnosing fibromyalgia syndrome (FMS), and lead to improved treatments.

Voila: Diagnosis

Fibromyalgia syndrome is diagnosed by pressing on 18 specific points. If 11 of these points feel tender when pressure is applied to them, voila, the patient is diagnosed with fibromyalgia (FMS). Not very scientific on the surface, and no one has really examined the makeup of these pain points. Furthermore, even when patients report that treatments bring on a significant improvement in their pain levels, the tender points count does not often decrease. What are these vague tender points and what do they signify?

Now consider myofascial trigger points (MTPs). These also cause pain. But along with pain, MTPs bring a restricted range of motion plus muscle tightness or weakness. MTPs tend to occur at the midpoints of the affected muscles but may also cause intense pain at areas where the muscles are attached to bones, or the muscle tendon junctions.

Referred Pain

The symptoms that result from pressure on MTPs are due to muscle shortening caused by sustained muscle fiber contraction. The MTP patient feels that a specific muscle is taut or tense, and may even feel a lump or knot at the site of contraction. Applying pressure to such a knot causes severe pain that is referred to nearby areas of the body.

Classic thought held to the position that the tender points of fibromyalgia only cause pain at those points and therefore were distinguishable from MTPs in that MTPs cause pain to radiate. The two research projects funded by AFSA are intended to explore the idea that this is a simplistic distinction that may be untrue. The studies hope to learn more about the tender points of FMS and whether they might share a connection with the trigger points of myfascial pain.

According to Robert Bennett, M.D., of Oregon Health Sciences University in Portland, “In reality, virtually every patient with fibromyalgia has numerous tender areas that generally occur in the vicinity of the muscle tendon junction. From a purely clinical point of view, these other tender areas usually fulfill the criteria for a myofascial trigger point.”