Pain is sometimes limited to the area where its source is located. For instance, if you burn your finger, the pain will be felt right where your finger was exposed to excess heat. Unfortunately, pain isn’t always this straightforward. Some discomfort originates in one place and spreads to other areas of your body. Here’s a closer look at how and why this could happen.
One way for pain to spread is by overcompensating for discomfort in one area of your body by changing the way you move. If you have chronic knee pain, for instance, you may begin to limp or shift how you walk. Doing this may, in turn, put added stress on muscles around your lower back. So, you could up with pain that’s now felt in your affected knee and your lumbar spine – and lower back pain could eventually extend to your hips and thighs.
Some people purposely avoid doing anything that triggers their pain. Doing so may unintentionally cause pain to spread. If your right hand hurts because of carpal tunnel syndrome, for example, you might start using your left hand more. What this can do is create the same problem in the other part of the body you now using more to avoid using the painful part. So, you could very well end up with carpal tunnel syndrome affecting both hands and wrists.
Muscle trigger points can also cause pain to spread. When this happens, it’s called referred pain. Trigger points are tight and tender areas that when irritated produce pain that can be localized or felt in nearby areas. Should the large muscle bundle (trapezius muscle) in the back of your neck, head, and shoulder be one of your trigger points, for instance, you could experience additional pain that includes:
- Jaw pain
- Eye pain
- Arm and/or finger pain
One other way for pain to spread is for a nerve to be irritated. This type of pain tends to be felt along the pathway of the affected nerve. A common example of what’s sometimes referred to as radiating nerve pain is sciatica. In this case, the sciatic nerve that originates in the lower back is irritated or compressed and discomfort is felt in the lower extremities since this nerve extends into the legs. Nerve-based pain may be experienced as:
- Numbness and tingling
- General muscle weakness
- Pins-and-needles sensations
- Burning sensations
If you have pain that has spread from its original source, you’ll need to undergo tests to determine what’s causing it. Typically, these efforts involve CT scans and other image tests and specialized testing that may include nerve conduction studies or image tests performed with a contrast dye. It’s important to identify your pain source so treatments can be focused on what’s causing your pain, not just the symptoms.