The Science Behind Wonky Body Things that Suck

A patient last week told me a story I’ve heard many times in many forms. She started experiencing chest pain that radiated down her left arm. She went to the hospital. There was nothing wrong with her that any test could reveal. She wasn’t having panic attacks and her heart was fine. She went from practitioner to practitioner before someone finally figured it out: it was muscular. In other forms of this story the symptom is abdominal pain, or diarrhea, or sinus congestion, or painful intercourse, or ear ringing, or acid reflux, but the common thread is that multiple doctors failed to consider that the origin was structural.

Often, these mystery symptoms – along with most cases of muscle pain – are caused by a phenomenon known as “myofascial trigger points,” and I believe everyone should know what they are and how they work. I’ve written about trigger points in the past, but I feel moved to explain some of the basics again because this concept remains largely unknown to both practitioners and laypeople. It’s not exactly a fringe idea either – it was developed primarily by President Kennedy’s personal doctor, Janet Travell (the first female White House physician, by the way), whom he credited with saving his political career after she cured his back pain. Her first journal article on the subject was published over 60 years ago.  

What exactly is a “myofascial trigger point” anyway? Basically, a trigger point is a small, irritable region in a muscle (or the surrounding connective tissue – “fascia”) that stays stuck in a contracted state and can produce pain, other sensory changes, tightness, and dysfunction. A unique property of trigger points is that they’re able to produce symptoms in other parts of the body – from a few inches to a couple feet away. One of the most valuable contributions of Travell’s work was to map out hundreds common locations of trigger points and their referral patterns – i.e., where they produce symptoms.

If you know where to look for trigger points that could be implicated in an issue, it’s usually pretty quick and straightforward to determine if this is the cause. And if so, you can often fix them yourself.

How do trigger points form?

There are a handful of mechanisms that can promote trigger point formation, such as irritation of nerves, chronic organ problems, nutritional deficiencies, and autoimmune disorders. More often, though, the cause is trauma to our connective tissue. When a muscle is strained by being worked too hard, too fast, or beyond its natural range, there is frequently a sort of “recoil” that occurs as segments of the muscle fibers bunch up and remain that way. This is common in people who work out without warming up, or who suddenly do a very ambitious workout after having not exercised for a year. Even more commonly, the trauma is a form of “postural stress” that’s demanding on muscles in a way that’s difficult to perceive at the time – such as doing the same relatively motionless activity (like sitting at a desk or driving) for hours, days, months, or years.

A muscle contracts through the action of nerve impulses – electrical signals that deliver the command to shorten. If you have nerve damage visit Neuropathy Help, they have tips on how to heal nerve damage. These impulses stream into the muscle for as long as we wish to hold this contraction. The impulses aren’t distributed throughout the muscle in an even way, though, and the muscle “belly” (the bulky contractile part) becomes slightly twisted during each contraction.

This isn’t usually a problem if we’re doing repeated isotonic contractions. Isotonic contractions are where the muscle causes movement and it alternately shortens and lengthens, working and relaxing. The issue lies more in prolonged isometric contraction or “static” contraction. That’s where a muscle stays contracted without movement – like the way you hold your arms up for hours while typing or driving. The muscle is under constant pressure and the continuous stream of nerve impulses produces a sustained deformation of the muscle belly.

I need a little more science to explain what happens next, so get ready. Over time, the ongoing tension and twisting of the muscle fibers causes an elevation in the resting muscle tone – that is, eventually, the muscle never completely relaxes. It’s always a bit contracted, meaning a bit shortened, and therefore a bit taut. This tightness causes local vasoconstriction – the blood vessels are constricted – and this translates to local ischemia – inadequate blood supply to the tissue (the same thing that happens to heart muscle in a heart attack). The arteries can’t bring in enough fresh blood and oxygen, the veins and lymphatic vessels can’t adequately drain waste and deoxygenated blood. The tissue pH changes, local metabolism is impaired, and fluid and waste products build up in the area.

This combination of factors ultimately activates pain receptors – it starts to hurt – and when this happens you use the affected muscle less. Instead, you overload “synergists” – nearby helper muscles. The body makes the surrounding musculature tense as a protective mechanism. Meanwhile, there’s a disruption of the balance between the affected muscles and their “antagonists” – those muscles that lengthen when the primary muscles shorten and vice-versa (for example, the triceps is an antagonist of the biceps). Altogether, this restricts natural movement of the original muscle, which just perpetuates the imbalance.

Over time, this situation results in the development of trigger points. A muscle is composed of numerous parallel fibers and each fiber consists of many end-to-end contractile segments called sarcomeres. When they’re working correctly, they all shorten together when you contract the muscle and then return to their resting length when you relax. But trigger points involve a collection of sarcomeres that remain in a shortened, irritable state, which makes them bulge (often causing a palpable “knot”) and causing their muscle fibers to feel taut and stringy. Finally, with longstanding trigger points, the body deposits gooey lubricant compounds called glycosaminoglycans (GAGs) between these triggered muscle fibers, resulting in a gummy lump called a “myogelosis.”

Ok, enough with the big words.

The point is, there are tons of resources in print and online to help you locate trigger points and show you the kinds of problems they can cause. As for getting rid of them, the most basic method is to simply press and hold an active trigger point when you find one. After about 30 seconds, you’ll usually feel it soften. You can also press down the trigger point (with a thumb, fingers, or a tool) and then move the tissue, as if deliberately intending to re-lengthen this shortened part of the muscle.

Acupuncture is really excellent at releasing trigger points. Dr. Travell injected various agents into trigger points to cause them to deactivate, but later in her career, she began to realize that the most effective part of this process was simply jabbing the trigger point with the end of a needle. There wasn’t a need to inject any liquid; thus, this method became known as “dry needling.” She worked with an osteopath acupuncturist named Dr. Mark Seem who developed an acupuncture-based methodology for releasing trigger points in a holistic way – that is, while supporting the body as a whole to restore balance. (If you’re interested in trying dry needling, I strongly recommend you receive it from an acupuncturist rather than a physical therapist, since acupuncturists have an exponentially greater amount of needle training and a more sophisticated understanding of how to treat the big picture.)

If all of this sounds interesting and relevant to you, I encourage you to do a little research. It might well be the end of a problem you thought had no solution. And if you need more guidance, check out my online course, Live Pain Free, where I go deeper into trigger points and much, much more to help people get out of pain of all kinds.

Be well,

Dr. Peter Borten, Coast2Coast First Aid/CPR – Brampton