Peripheral Neuropathy and Fibromyalgia

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Have you ever heard of peripheral neuropathy? If you don’t deal with chronic pain conditions, odds are good that you haven’t encountered this particular piece of medical jargon. But if you have a condition like fibromyalgia, peripheral neuropathy might actually play a significant role in your disease and it’s symptoms.

In fact, some people have even suggested that it might be at the root of fibromyalgia. But what exactly is peripheral neuropathy? And how does it relate to fibromyalgia?

What Is Peripheral Neuropathy?

Neuropathy is, to break the word down,  a disorder (pathy) related to the nerves (neuro). And peripheral neuropathy is a disorder of the nerves that extends throughout the peripheries of the body (so beyond the brain, basically).  And since the nerves connect the body and the brain and are responsible for physical sensations like pain, a breakdown in this connection can lead to serious problems.

The nerves transmit signals from the skin to the brain, which the brain then interprets and sends back down the nerves. This is why you feel pain in your hand when you touch a hot stove. You’re not actually feeling pain in your hand, the sensation of pain is coming from your brain. But your brain relies on the signals from your hand to know that you are being injured and it signals that your hand is hurting as you pull it away. This system helps us avoid serious injuries.

But when it comes to people dealing with nerve pain conditions, those signals get crossed, and your brain starts triggering pain signals without any actual injury.

And there are many different kinds of this condition depending on where in the body they occur and how severe they are but there are two main categories: mononeuropathy and polyneuropathy.

Mononeuropathy means that only a single nerve connection is damaged. Injuries are the most common cause of mononeuropathy. A good example is carpal tunnel syndrome, which is caused when a repetitive stress injury in the hands and wrist damages the nerves in the hand. Polyneuropathy occurs when several nerve connections are damaged. Diabetes is a good example.

And in all forms of neuropathy. The damaged nerves cause pain, numbness, and tingling. And the symptoms can range from a minor annoyance to very severe.

Neuropathy and Fibromyalgia

The idea of pain with no obvious cause probably sounds familiar to people who suffer from fibromyalgia. And nerve damage might play a much larger role in the condition than you suspect. A study conducted by a Harvard-affiliated hospital in Massachusetts found that almost half of the fibromyalgia patients in the study had evidence of something called small nerve fiber neuropathy.

Small nerve fiber neuropathy is basically nerve pain caused by damage to some of the small nerves that carry pain and touch signals from the skin to the brain.  As that study demonstrated, half of all fibromyalgia patients have the condition. And many also have less of these small nerve fibers than they should.

This implies that the root of fibromyalgia pain might actually be neuropathy in some patients. Their brains are sending pain signals even though there’s no actual damage. This would explain the mystery pain, but there are a few problems with presenting neuropathy as a comprehensive explanation of fibromyalgia.

To begin with, not all patients with fibromyalgia have small nerve fiber neuropathy. So, this theory doesn’t explain what’s going on in those patients. And it doesn’t explain why these patients are developing neuropathy in the first place

But the fact that half of all fibromyalgia patients have small nerve fiber neuropathy implies that something is going on. Some people have suggested that what is actually going on is that a significant portion of people who have been diagnosed with fibromyalgia are actually suffering from small nerve fiber neuropathy, but because the symptoms are so similar, it’s difficult to tell them apart.

It’s an interesting theory, and because small fiber neuropathy is treatable, it could shift the way we treat fibromyalgia. And it is especially interesting because, if true, it might mean that fibromyalgia is actually not a single condition but a wide spectrum of neuropathic conditions all presenting similar symptoms. Luckily, there is a simple test that you can get to determine if you have small fiber neuropathy called a “punch biopsy.”

So if you have fibromyalgia, it may be worth looking into getting this test, because it might mean having access to new treatment options. And this new way of looking at fibromyalgia may even help us steer research to a breakthrough. At the moment, this remains a theory, but it is an interesting one.

So tell us what you think? Is fibromyalgia actually a few different conditions rather than one? Have you been tested for small fiber neuropathy? Let us know in the comments.