How Trigger Points Work — Muscle Knots & Referred Pain

Some of the most stubborn, most misdiagnosed pain in medicine comes from something deceptively simple: a knot in a muscle. Understanding how these "trigger points" form — and why they cause pain far from where they live — explains a great deal of pain that conventional tests can't find.

What tension does to muscles

A healthy muscle contracts when you use it and relaxes when the work is done. But a muscle under stress or affected by trauma can contract and stay tensed. Held that way long enough, it can go into spasm and lose the ability to relax at all. Muscles that are weak and stiff from lack of exercise are especially vulnerable — tension builds faster in them, which is part of why regular activity is protective.

What is a trigger point?

When a muscle stays knotted, blood can't circulate properly through the tissue to nourish it. Over time some of that tissue degenerates into small, palpable nodules — trigger points. These little knots are a major source of the severe pain associated with muscle-strain problems. And crucially, each muscle tends to refer its pain in a characteristic pattern, so once you know the pattern, you can work backward from where it hurts to find the muscle actually causing it.

Why trigger points cause pain somewhere else

Here's what makes trigger points so tricky: a trigger point can refer pain to a part of the body far removed from its source. A trigger point in your shoulder muscle can be the true cause of pain in your temple — and if you press that shoulder knot, you can often feel the pain shoot up to the temple, proving where it really originates. Someone unaware of the trigger point might reasonably mistake that throbbing one-sided head pain for a migraine. It's a common misdiagnosis. (This is the same referred-pain principle covered on our referred pain page, applied specifically to muscle.)

Why trigger points cause "diagnostic havoc"

Trigger points can occur anywhere and cause confusion wherever they appear. In the neck and shoulders, they produce pain mistaken for migraine. In the buttocks, they cause back discomfort often confused with a spinal disc problem. And here's the core issue: they don't show up on conventional imaging or tests, and most physicians don't examine the muscles for them — so they may be among the single greatest causes of misdiagnosis in chronic muscle-contraction pain.

Worse, they're self-reinforcing. An untreated trigger point causes pain, the pain makes you tense, the tension makes the muscle contract harder, and that produces more trigger points and more pain — the same self-feeding loop described on our Breaking the Pain Cycle page.

The encouraging part

Because trigger points are a mechanical problem, they respond well to mechanical treatment: stretching, and where needed, trigger point injections that release the knot directly (see our nerve blocks and injections page). The key is simply that someone has to examine the muscles and recognize them — which is exactly what a pain specialist does. If you've been told your imaging is "normal" but your pain is very real, muscle trigger points may be the missing piece. Call Newport Pain Management at (949) 759-8400.

This article is for general education and is not a substitute for individual medical advice.