I hear it just about everyday. I don’t know how or why people think it. There is no known conspiracy about it. It may be because it is the only explanation people can think of. It drives me crazy and takes all of my energy to control my emotions when I hear, “I think it’s just a muscle.”
Let me explain why it is never just a muscle when you are talking about back and neck pain. The muscles in the back and neck are slow twitch muscle fibers. They are designed for endurance. They are not fast twitch, speed muscles. In addition, there are three layers of muscles with a ton of overlap amongst the muscles of each layer. For this reason, it is nearly impossible to tear or “pull” one of these muscle without doing damage to a much more susceptible structure first.
The most common tissue to receive damage in the spine is the disc which can bulge, herniate, mishape, and swell when over worked or over loaded. Then there are the joints and ligaments of the spine which will sprain long before a postural muscle reaches tearing status. Finally, you have the nerve roots which if irritated even slightly will cause a muscle spasm which essentially protects the muscle. Herein lies the issue.
When a muscle spasms it can be a lot more painful and noticeable than the underlying cause. Don’t be fooled. Muscles don’t just decide to spasm on their own. It is a protective measure.
There can be occasions where a muscle due to overuse, usually because of postural strains, will form a knot (the technical term being a trigger point). When this happens it is commonly like asking, “which came first the chicken or the egg.” If there is a trigger point it will immediately affect the joints, discs, and nerves. There will also be a good argument that the trigger point only developed because of a lack of motion or subluxation of the joints. Either way, it is never just a muscle.