Edzard Ernst recently commented on two Cochrane reviews involving chiropractic, which drew my attention to these reviews. I have to admit finding the results a little surprising.
In general, the total body of evidence fails to support most of the claims chiropractors make about the nature of illness and the beneficial effects of chiropractic. However, there has been some decent research evidence to support chiropractic as a treatment for uncomplicated lower back pain, no more nor less effective than conventional treatment. Despite the theoretical problems with chiropractic, and all the associated nonsense (colon cleansing, cold laser therapy, supplements, and so on), I’ve always accepted that at least there is some legitimate role for chiropractic treatment in the management of back pain.
However, the Cochrane reviews that Dr. Ernst reports cast some doubt on even this claim. The updated review of spinal manipulative therapy finds good quality evidence only for ” a small, statistically significant but not clinically relevant, short-term effect on pain relief.” The reviewers could not determine whether this effect is any greater than placebo because only poor quality studies with a high risk of bias investigated this question.
Chiropractors, or at least “mixers,” often claim that they do more than just manipulate the spine. A new review looked at research for this combined chiropractic interventions for low back pain. The conclusions:
while combined chiropractic interventions slightly improved pain and disability in the short term and pain in the medium term for acute and subacute low-back pain, there is currently no evidence to support or refute that combined chiropractic interventions provide a clinically meaningful advantage over other treatments for pain or disability in people with low-back pain. Any demonstrated differences were small and were only seen in studies with a high risk of bias.
So the best we can say is that spinal manipulation alone has a small, short-term impact on back pain, probably not enough to matter to patients and certainly no better than conventional therapy. Combined or “holistic” chiropractic care does no better. So the research evidence, after more than a hundred years of study since chiropractic was invented, clearly shows no benefit for any problem other than uncomplicated lower back pain. And even for this indication, the benefit is small, possibly no greater than placebo and certainly no greater than conventional therapy. So is this benefit worth being exposed to the rampant pseudoscience promulgated by so many chiropractors, the aggressive marketing of “preventative” chiropractic treatment, and all the other nonsense that so often accompanies most chiropractic treatment?