Wednesday, July 29, 2009

Participating in the Internet: Beware the spinal trap

So there's been a bunch of to-do about Simon Singh, the science writer who said "bogus" when he probably meant to say "bullshit" and is being sued for libel. Personally, I don't know what's wrong with the Britich Chiropractic Association - they can't even make acronyms properly, it ought to be the British Association of Chiropractors, making it a proper backronym! Anyway, Orac has the scoop, PZ has joined in, and others have as well. There are alterations in these at the request of SAS (Sense About Science, not the British commandos), on the grounds that they could still get Singh in trouble. Whether or not that's true - and in a country without our robust protections of free speech, it may well be - I don't think the factual claims made in his article are affected by the presence or absence of the word "bogus." At any rate, as a gesture of journalistic aptitude, here is the internet cache of the original article. Below is the "current" version:
Some practitioners claim it is a cure-all, but the research suggests chiropractic therapy has mixed results - and can even be lethal, says Simon Singh.

You might be surprised to know that the founder of chiropractic therapy, Daniel David Palmer, wrote that "99% of all diseases are caused by displaced vertebrae". In the 1860s, Palmer began to develop his theory that the spine was involved in almost every illness because the spinal cord connects the brain to the rest of the body. Therefore any misalignment could cause a problem in distant parts of the body.

In fact, Palmer's first chiropractic intervention supposedly cured a man who had been profoundly deaf for 17 years. His second treatment was equally strange, because he claimed that he treated a patient with heart trouble by correcting a displaced vertebra.

You might think that modern chiropractors restrict themselves to treating back problems, but in fact some still possess quite wacky ideas. The fundamentalists argue that they can cure anything, including helping treat children with colic, sleeping and feeding problems, frequent ear infections, asthma and prolonged crying - even though there is not a jot of evidence.

I can confidently label these assertions as utter nonsense because I have co-authored a book about alternative medicine with the world's first professor of complementary medicine, Edzard Ernst. He learned chiropractic techniques himself and used them as a doctor. This is when he began to see the need for some critical evaluation. Among other projects, he examined the evidence from 70 trials exploring the benefits of chiropractic therapy in conditions unrelated to the back. He found no evidence to suggest that chiropractors could treat any such conditions.

But what about chiropractic in the context of treating back problems? Manipulating the spine can cure some problems, but results are mixed. To be fair, conventional approaches, such as physiotherapy, also struggle to treat back problems with any consistency. Nevertheless, conventional therapy is still preferable because of the serious dangers associated with chiropractic.

In 2001, a systematic review of five studies revealed that roughly half of all chiropractic patients experience temporary adverse effects, such as pain, numbness, stiffness, dizziness and headaches. These are relatively minor effects, but the frequency is very high, and this has to be weighed against the limited benefit offered by chiropractors.

More worryingly, the hallmark technique of the chiropractor, known as high-velocity, low-amplitude thrust, carries much more significant risks. This involves pushing joints beyond their natural range of motion by applying a short, sharp force. Although this is a safe procedure for most patients, others can suffer dislocations and fractures.

Worse still, manipulation of the neck can damage the vertebral arteries, which supply blood to the brain. So-called vertebral dissection can ultimately cut off the blood supply, which in turn can lead to a stroke and even death. Because there is usually a delay between the vertebral dissection and the blockage of blood to the brain, the link between chiropractic and strokes went unnoticed for many years. Recently, however, it has been possible to identify cases where spinal manipulation has certainly been the cause of vertebral dissection.

Laurie Mathiason was a 20-year-old Canadian waitress who visited a chiropractor 21 times between 1997 and 1998 to relieve her low-back pain. On her penultimate visit she complained of stiffness in her neck. That evening she began dropping plates at the restaurant, so she returned to the chiropractor. As the chiropractor manipulated her neck, Mathiason began to cry, her eyes started to roll, she foamed at the mouth and her body began to convulse. She was rushed to hospital, slipped into a coma and died three days later. At the inquest, the coroner declared: "Laurie died of a ruptured vertebral artery, which occurred in association with a chiropractic manipulation of the neck."

This case is not unique. In Canada alone there have been several other women who have died after receiving chiropractic therapy, and Edzard Ernst has identified about 700 cases of serious complications among the medical literature. This should be a major concern for health officials, particularly as under-reporting will mean that the actual number of cases is much higher.

If spinal manipulation were a drug with such serious adverse effects and so little demonstrable benefit, then it would almost certainly have been taken off the market.

Simon Singh is a science writer in London and the co-author, with Edzard Ernst, of Trick or Treatment? Alternative Medicine on Trial. This is an edited version of an article published in The Guardian for which Singh is being personally sued for libel by the British Chiropractic Association.
Update: We have something of an expert opinion on this, right in the comments! Dale, the first commenter, has posted some good points which have precipitated a further response of my own. Depending on how involved the discussion gets, this may be followed up on in another post (due to space restrictions in the comments). Stay tuned!


Dale said...

This info is out of date. Current literature shows that the incidence of stoke after a Chiropractic treatment is just as high as walking down the street, or seeing your general practitioner. The reason that there is a correlation between stoke and chiropractic manipulation is that the first signs of a vertebral artery stoke are neck pain and headaches. Which doctor will people go to when they experience those symptoms? Typically they'll go to the chiropractor. Yes it's the chiropractor's job to distinguish the difference between neck pain and the beginnings of a stroke but there is no direct causality between manipulation and stroke. Also quoting DD Palmer from the 1800's is ridiculous, remember the founding fathers of the MD world used to drill holes in peoples heads to cure disease. Finally the chiros out there that believe they can treat everything are the minority out there in the real world, but they make the most noise so they get the most attention.

D said...

Wow, thanks for your contribution! Information like this - the fact that Singh's figures are out of date, and your point on the ambiguity of the "chiropractor visit and then stroke" correlation, specifically - is why I refrained from extended comment on the situation. I'm not an expert.

This isn't about expertise, though, it's about free speech. While Britain's protections of free speech are not as robust as our own (neither in principle nor in practice), the principle still stands that telling the truth should not be punishable under law (including the act of placing undue and asymmetrical duress upon a defendant). While Singh certainly ought to back up his claims, as it stands, he is guilty of libel until proven innocent; by stark contrast, no burden of proof whatsoever is due from the BCA, and they can in theory litigate until he's bankrupt without ever needing to provide a scrap of evidence. My worry is that this may become a dangerous precedent for the enshrining of woo, as Singh may be unable to continue legal proceedings until facts from all sides are given a thorough analysis; in other words, the case may devolve into a shouting match or money contest, rather than being about the fact of the matter.

I posted this article as part of a deliberate reaction to an act of censorship, much like a person might deliberately read a banned book: I am trying to circulate this opinion specifically because it is being oppressed in what I consider to be an unfair way. I'm fighting censorship, in other words, and not the practice of chiropractic.

I fully support any person who attempts to change the public perception of anything and in any direction by reference to peer-reviewed research, and I also support chiropractic in general as an "underdog" (insofar as that status is perpetuated by lack of research funding and other institutional roadblocks, not simply because it is an underdog). My take on this situation is that it is a hairy one, and chiropractic benefits from the woo of the general public. I believe we share the opinion that the quacks ought to be shut down, the woo ought to be excised, and more research is due (but this is itself a problematic issue for both ethical and economic reasons). As for Palmer, the problem is that his writing is often treated religiously - I do in fact mean that pejoratively, but only insofar as his writing is accepted uncritically as the Truth (this is only done by quacks, though).

I hope this clears up any misunderstanding, and thanks again for your contribution!

D said...

I misused "oppressed." It should read, "I am trying to circulate this opinion specifically because it is being suppressed in what I consider to be an unfair way." (Emphasis altered.)