Mar 02 2007

Nerve Nonsense – Beware of Quack Devices

About 2.4% of the population has some kind of peripheral nerve damage (neuropathy), which means there are about 7.2 million Americans with neuropathy. In most cases there is no cure (although there is effective treatment for some of the symptoms of neuropathy) so it is not surprising that neuropathy is a common target for questionable treatments and devices.

I came across this ad for The Rebuilder and it is just chock full of misleading or unsupported claims and blatant misinformation. It’s also a good example of the many features of quackery marketing to look out for.

FDA Approved

The Rebuilder website claims that their device is an “FDA approved medical device,” which is true but misleading. They provide a link, which at first I thought was to the FDA site for verification, but when I could not navigate the site I realized it was just a static picture of the FDA site. It was clear why they did this once I found the actual current FDA entry, which states: “The product known as “the rebuilder” is only FDA approved for pain relief. However, it is being marketed to consumers as “approved for neuropathy.” This is very misleading and the device can get hot or burn if not used properly.”

This is a common ploy for medical devices. Often the FDA approves a device as safe and that it does what it is supposed to do – meaning that if it says it produced radio waves of a certain frequency that its does in fact produce the waves. However, unlike for drugs, the FDA does not always investigate the medical applications of the device. A good example is acupuncture needles, which are medical devices that require FDA approval. However, the FDA does not investigate or approve acupuncture as an intervention – just the needles.

But slapping the FDA approved label on the website is a good marketing ploy, as most readers won’t take the time and effort to go directly to the FDA site to verify what it actually says.

Claims based upon anecdotes or vague references to research.

The Rebuilder home page has numerous claims that are essentially just reporting the anecdotal experience of an individual. Anecdotes are worthless as evidence because they are cherry picked data. You could find anecdotal evidence to support any treatment, even a harmful one. They also refer to a “recent study” but do not give a reference – which means you should not trust the claim. Studies are only useful if the methods are valid and the results have been reviewed (and hopefully replicated). Companies often hire independent groups to conduct studies to validate claims for their devices or supplements – and it is no surprise they get the results they want, often results that are far too good to be true. In this cast they claim a 95% response rate – I have never seen a valid study for an intervention for pain or any other symptom for that matter that had a 95% response rate.

How does it work?

The Rebuilder website says, “The ReBuilder® uses a tiny electrical signal to wake up nerves that are temporarily dormant or asleep due to past oxygen deprivation. The ReBuilder’s patent pending signal is a precise copy of a healthy nerve signals, but stronger. This healing signal travels from one foot, up that leg, across the synaptic junctions and nerve roots in your lower back and then down to your other foot. Then it reverses the polarity and this nerve impulse then travels back to your original foot.”

This is pure nonsense. First, it oversimplifies the very concept of neuropathy. Neuropathy is not a specific disease or cause – it refers to any type of nerve damage. Nerve damage can be traumatic, toxic, an inherited problem with the structure of the nerve, due to inflammation, due to a host of metabolic factors (the most common by far being diabetes), and many other causes. The mechanism of damage for each cause is different, yet Rebuilder pretends that the cause is all the same – lack of oxygen. I suspect they chose lack of oxygen simply because it sounds good and people can understand it. In fact, lack of oxygen has been specifically ruled out as a cause of diabetic neuropathy – the most common type.

The ridiculous statement also assumes that all types of neuropathy involve nerves that are “temporarily asleep.” Actually there are numerous methods for evaluating nerve health and function and can document anatomical damage to the nerves of various types. The two most common types of damage are axonal and demyelinating. Axonal damage refers to die back of the nerve axon itself – the axon being the “wire” that connects the nerve cell body to either another nerve cell, a muscle, or a sensory organ. Myelin is the insulation around axons – it allows the axons to conduct their electrical current much quicker. Processes that damage or strip the myelin slow down nerve conduction.

When pain is due to neuropathy there are also a host of causes for this as well, for example changes in the properties of ion channels or neurotransmitters that make sensory nerve too sensitive to stimulation, or make them produce abnormal pain signals on their own.

None of this can be meaningfully characterized as nerves being “asleep.”

The description of the nerve impulse is laughably absurd. What does it mean, for example, that the impulse duplicates the signal in a healthy nerve? I also like how they have the signal jumping from one foot to the other and back again through apparently imaginary pathways. But the notion that electrical stimulation can improve the function of muscles and nerves, which are electrical organs, has been investigated for decades and has been found to be essentially false. The idea is very appealing, and makes a certain amount of naïve sense, but it has just turned out experimentally to be untrue.

So damaged nerves often have dead axons, stripped myelin, and/or abnormal ion channels – you can’t simply wake them from their slumber by shocking them.

But the nonsense goes further. They make up out of whole cloth, as far as I can tell, the idea that neuropathy is caused by the synapse between two neurons widening – and of course the Rebuilder rebuilds this connection. But this is not based upon any real science. First of all, most neuropathy does not involve any interneuronal connections. Sensory nerves, for example, have their cell bodies in ganglia just outside the spinal cord and their sensory organs in the skin. So this is a single cell and a single axon – there are not interneuronal synapses until you get to the spinal cord, and by definition you are no longer dealing with a peripheral neuropathy but a central disorder. Neuropathy occurs typically in the axon itself, not with any connection.

Trash the competition

The Rebuilder website says: “Another factor to consider is the negative side effects that your prescription medicines may have on your neuropathy. These powerful drugs work by interfering with the signals from your extremities, so that the brain does not receive these signals. This is performed at the nerve roots of your lower back. This may help the pain for a while, but soon your body will accommodate, and require a higher dose.”

Totally false. Drugs for neuropathic pain do inhibit pain signals through damaged nerves, but their effect is primarily on abnormally generated signals – not normal signals. They do not cause or exacerbate numbness, and they do not interfere with any natural healing that nerves may experience. Besides, stopping pain signals from getting to the brain is the whole point. They also do not work at the nerve roots, either at all or exclusively. This is just a bizarre random bit of misinformation that makes me think the marketers of this device were grabbing random phrases from textbooks or websites on neuropathy but don’t have any idea what they are actually talking about.

It is further a complete fabrication to say that the body accommodates to these medications (here I am talking specifically about drugs for nerve pain – not narcotics or other generic pain killers). There is no tolerance to these medications, in fact if anything they work better over time – the abnormal pain signals may calm down with long term treatment.

It is true that these drugs treat only pain and other positive symptoms (like tingling) and do nothing for numbness. Neither does the Rebuilder, but they boldly claim that it does cure numbness, without providing any valid scientific evidence.

Take credit for normal healing

Nerves in the peripheral nervous system can repair themselves. They can make new myelin and even regrow dead axons. After an injury, in an otherwise healthy individual, there is often significant nerve recovery. Chronic diseases, however, like diabetes, are always present so they do not provide an opportunity for nerves to recover. It is an active area of research to find out how to coax nerves to regenerate faster and more completely, or in conditions like diabetes where they do not normally regenerate spontaneously. Unfortunately, this research has not lead to any effective treatments – it’s proven to be a tough nut to crack. But it’s likely we will have effective treatments in the future – we know that nerves have the capacity to regenerate so this should be a solvable problem.

At present the most effective treatment for any neuropathy is to cure or control the underlying cause. So if you are a diabetic, keep your blood sugar under tight control. If you drink too much alcohol – stop. Also there is some evidence that basic nutritional support it necessary and helpful for optimal nerve healing. Specifically, vitamin B6 (in normal but not excessive amounts – megadoses are actually toxic to nerves) can help with nerve healing. But this common sense basic support is all we have at present.
But this natural healing is likely to generate a lot of testimonials for all sorts of ineffective or pseudoscientific treatments, like this one. If you have a nerve injury, then use some random ineffective treatment, the nerve is likely to improve and the treatment will get the credit.

The only solution, of course, is to conduct carefully controlled clinical trials. That is the only way to really know if something works or not. So far Rebuilder has not provided this kind of evidence (the only acceptable kind) to support their claims, and I’m not holding my breath.

4 responses so far