Why Do I Get Myofascial Trigger Points? Part One: Muscles
Myofascial pain syndrome is a chronic pain condition that is felt by patients deep within their muscles. The word “myofascial” comes from two root words – “myo” which means muscles and “fascia” which is the thin connective tissue surrounding the muscles. A patient suffering from myofascial pain syndrome has myofascial trigger points, which are tender spots in the muscle that can feel like a hard muscle knot. They can cause pain at the specific spot as well as in other areas, known as referred pain.
We do not know exactly why myofascial trigger points occur. There are many theories for what leads to their formation. These theories involve muscles, a connective tissue layer called fascia, and nerve networks. This blog will focus on a couple of muscle theories. Interestingly, as the research unfolds it appears that the answer may involve a combination of various theories working together in a complex way.
Chronic Muscle Imbalance: Little Red Hen Hypothesis
Muscles can be classified into two main categories: dynamic and postural muscles. We use dynamic muscles when we are moving. Postural muscles are mostly engaged when we are in a prolonged position or activity.
The chronic muscle imbalance hypothesis posits that trigger points are formed because of muscle imbalance. As the story goes, the little red hen was surrounded by lazy friends and found she was doing all the work of planting and harvesting the wheat, grinding it into flour and baking it into bread. This is not a sustainable situation; the barnyard friends must be engaged to pull their share of the load and to protect the little red hen from burnout.
The little red hen hypothesis theorizes that spending more time in a sedentary lifestyle can cause your dynamic muscles to become weak and loose, while your postural muscles become tight and stiff. When our muscles become unbalanced, our body tries to compensate by either using tight and stiff muscles or weak and loose muscles, creating a difficult situation that can lead to muscle injuries and pain. As a result, myofascial trigger points may form.
Cinderella Hypothesis
The Cinderella hypothesis proposes that certain muscles are overworked and overloaded; and much like our beloved heroine, the “Cinderella” muscles are those that get worked the most. They get recruited first and work until the job is done. When we are in a prolonged position or activity requiring low to moderate physical exertion, it’s the “Cinderella” muscles doing the work.
As a result, the “Cinderella” muscles are more susceptible to injury and breakdown. In this theory, there is not enough blood pumping through these muscles to support the production of ATP (the cell’s energy source), provide necessary oxygen and vital nutrients, and clear away build-up of metabolites. This overtaxed environment causes a vicious cycle of muscle fibers that are unable to relax, which reduces blood flow, and subsequently triggers the release of sensitizing chemicals that cause pain and muscle tenderness.
While we don’t know for sure why myofascial trigger points happen, it's important to correct muscle imbalances to keep muscles healthy and prevent pain. When you find yourself in pain from myofascial trigger points, it is essential to address muscle imbalances and stay active to avoid them in the future. Proper treatment should include addressing these imbalances and maintaining a healthy and active lifestyle to prevent further issues with myofascial trigger points.
References:
Shah JP et al. Myofascial Trigger Points Then and Now: A Historical and Scientific Perspective. PMR 2015 7(7):746-761.
Yap EC et al. Myofascial Pain - An Overview. Ann Acad Med Singap. 2007. 36:43-8.
