From time to time I answer questions from reporters about alternative medicine. In general, the coverage given my comments has been accurate and fair. One such accurate a fair representation of my words appeared recently in Readers Digest: "Over the years, a number of my patients have had strokes after chiropractic neck manipulation. It can cause something called vertebral artery dissection, where the main artery leading to the back of the brain actually splits. Now I tell patients, if you want to see a chiropractor, fine, but never let him touch your neck."
Shortly after this was published, I began to receive phone calls and letters from chiropractors around the country. They were not happy. Here's a typical example: "Dear [Dr Pal],
"Really! You really felt the need to outright lie in a national publication. 'Over the years, a number of my patients have had strokes after chiropractic neck manipulation.' A number of your patient's [sic], you lie. I am willing to bet you have never had a case of stroke caused by chiropractic among your patients. This issue of stroke and chiropractic has been studied and studied. It's been proven that the odds of a stroke after a chiropractic adjustment are infinitesimally small yet you lied.
"I was going to quote the studies conducted by the Canadian government and NIH and give you statistics from my malpractice carrier, the largest insurer of chiropractors in the United States to prove you wrong, but you already know you lied. I don't have to prove it to you.
"Watch next month's issue of Reader's Digest to the publication having to correct its outrageous error in printing your lie.
"I don't know what your motivation was and I really don't care. I just wanted you to know that 'we' as a profession know you lied and the majority of the public who have benefitted [sic] from safe chiropractic care know your profession has a history of failure and safety that will always surpass my profession by a high margin."
Unfortunately, most of the mail has been about this quality, with statements such as "you lie" and "I would give you safety statistics but I don't want to."
I am sure there are better defenders of chiropractic neck manipulation out there, but so far I haven't heard from them. The letter basically consists of multiple accusations of lying. Of course, he has no way to know if I'm lying or not, and if he knows anything about confidentiality, he knows that it would be unwise for me to give him specific numbers of patients. I can tell you that the number isn't large, but is certainly greater than one. I certainly cannot show him charts to prove anything.
And of course, correlation does not prove causation. It may be that these patients, who had vertebral artery dissections shortly after chiropractic neck manipulation represent coincidences. Plausibility and the medical literature suggest causation however.
He apparently also has an ax to grind with real doctors about our "history of failure and safety." That's an old saw from altmed folks that I've addressed many, many times, and I'll leave it to the archives for now.
The evidence in the literature is quite clear. Vertebral artery dissection (VAD), a type of stroke, is associated with chiropractic neck manipulation. It is not a common outcome, perhaps 1.5/100,000 manipulations, but it happens. What's left is a somewhat subjective decision regarding the risks vs. benefits of the procedure.
VAD is an uncommon type of stroke that affects the back of the brain. Rather than go into the details, I think we can all agree that strokes are a bad outcome, and that if a procedure carries that risk, it better have a lot of benefit. For example, coronary artery bypass surgery carries a definite risk of stroke, but the benefits are strong: bypass helps people with heart disease live better and longer, and in many cases saves lives. The risk of stroke is often less than the risk of not having surgery.
The best literature has failed to show a significant benefit of chiropractic neck manipulation vs. more conservative therapy for the treatment of neck pain.
What we have here is an intervention that carries a small but real risk of a catastrophic complication, whose benefits are unclear at best. While I don't recommend chiropractic treatment to my patients, for those who use it I give them this information. I succinctly tell them that they should not let a chiropractor manipulate their neck. It's just not worth it. I do the same for "mainstream" medical therapies whose risk benefit ratios are not favorable. It's just good medicine.
Reuter, U., Hamling, M., Kavuk, I., Einhaupl, K., Schielke, E. (2006). Vertebral artery dissections after chiropractic neck manipulation in Germany over three years. Journal of Neurology, 253 (6), 724-730 DOI: 10.1007/s00415-006-0099-x
Norris JW, Beletsky V, & Nadareishvili ZG (2000). Sudden neck movement and cervical artery dissection. The Canadian Stroke Consortium. Canadian Medical Association Journal, 163 (1), 38-40 PMID: 10920729
Rothwell DM, Bondy SJ, & Williams JI (2001). Chiropractic manipulation and stroke: a population-based case-control study. Stroke, a journal of cerebral circulation, 32 (5), 1054-60 PMID: 11340209
Ernst, E. (2003). Chiropractic spinal manipulation for neck pain: a systematic review. The Journal of Pain, 4 (8), 417-421 DOI: 10.1067/S1526-5900(03)00735-1
Peter A. Lipson, ACP Member, is a practicing internist and teaching physician in Southeast Michigan. After graduating from Rush Medical College in Chicago, he completed his internal medicine residency at Northwestern Memorial Hospital. This post first appeared at his blog, White Coat Underground. The blog, which has been around in various forms since 2007, offers "musings on the intersection of science, medicine, and culture." His writing focuses on the difference between science-based medicine and "everything else," but also speaks to the day-to-day practice of medicine, fatherhood, and whatever else migrates from his head to his keyboard.