In 2010, I have reviewed the deaths which have been reported after chiropractic treatments. My article suggested that 26 fatalities had been published in the medical literature and many more might have remained unpublished. The alleged pathology usually was a vascular accident involving the dissection of a vertebral artery. Whenever I write about the risks of spinal manipulation, chiropractors say that I am irresponsible and alarmist. Yet I believe I am merely doing my duty in alerting health care professionals and the public to the possibility that this intervention is associated with harm and that caution is therefore recommended.
Fortunately, I am not alone, as a new report from China shows.This review summarised published cases of injuries associated with cervical manipulation in China, and to describe the risks and benefits of the therapy.
A total of 156 cases met the inclusion criteria. They included the following problems: syncope = 45 cases , mild spinal cord injury or compression = 34 cases, nerve root injury = 24 cases, ineffective treatment or symptom increased = 11 cases ; cervical spine fracture = 11 cases, dislocation or semiluxation = 6 cases, soft tissue injury = 3 cases, serious accident = 22 cases including paralysis, death and cerebrovascular accident. Manipulation including rotation was involved in 42.00%, 63 cases). 5 patients died.
The authors conclude that “it is imperative for practitioners to complete the patients’ management and assessment before manipulation. That the practitioners conduct a detailed physical examination and make a correct diagnosis would be a pivot method of avoiding accidents. Excluding contraindications and potential risks, standardizing evaluation criteria and practitioners’ qualification, increasing safety awareness and risk assessment and strengthening the monitoring of the accidents could decrease the incidence of accidents” (I do apologize for the authors’ poor English).
It is probable that someone will now calculate that the risk of harm is minute. Chinese traditional healers seem to use spinal manipulation fairly regularly, so the incidence of complications would be one in several millions.
Such calculations are frequently made by chiropractors in an attempt to define the incidence rates of risks associated with chiropractic in the West. They look convincing but, in fact, they are complete nonsense.
The reason is that under-reporting can be huge. Clinical trials of chiropractic often omit any mention of adverse effects (thus violating publication ethics) and, in our case-series, under-reporting was precisely 100% (none of the cases we discovered had been recorded anywhere). This means that these estimates are entirely worthless.
I sincerely hope that the risk turns out to be extremely low – but without a functioning reporting system for such events, we might as well read tea-leaves.
The UK General Chiropractic Council has commissioned a survey of chiropractic patients’ views of chiropractic. Initially, 600 chiropractors were approached to recruit patients, but only 47 volunteered to participate. Eventually, 70 chiropractors consented and recruited a total of 544 patients who completed the questionnaire in 2012. The final report of this exercise has just become available.
I have to admit, I found it intensely boring. This is mainly because the questions asked avoided contentious issues. One has to dig deep to find nuggets of interest. Here are some of the findings that I thought were perhaps mildly intriguing:
15% of all patients did not receive information about possible adverse effects (AEs) of their treatment.
20% received no explanations why investigations such as X-rays were necessary and what risks they carried.
17% were not told how much their treatment would cost during the initial consultation.
38% were not informed about complaint procedures.
9% were not told about further treatment options for their condition.
18% said they were not referred to another health care professional when the condition failed to improve.
20% noted that the chiropractor did not liaise with the patient’s GP.
I think, one has to take such surveys with more than just a pinch of salt. At best, they give a vague impression of what patients believe. At worst, they are not worth the paper they are printed on.
Perhaps the most remarkable finding from the report is the unwillingness of chiropractors to co-operate with the GCC which, after all, is their regulating body. To recruit only ~10% of all UK chiropractors is more than disappointing. This low response rate will inevitably impact on the validity of the results and the conclusions.
It can be assumed that those practitioners who did volunteer are a self-selected sample and thus not representative of the UK chiropractic profession; they might be especially good, correct or obedient. This, in turn, also applies to the sample of patients recruited for this research. If that is so, the picture that emerged from the survey is likely to be be far too positive.
In any case, with a response rate of only ~10%, any survey is next to useless. I would therefore put it in the category of ‘not worth the paper it is printed on’.
If I had a pint of beer for every time I have been accused of bias against chiropractic, I would rarely be sober. The thing is that I do like to report about decent research in this field and I am almost every day looking out for new articles which might be worth writing about – but they are like gold dust!
“Huuuuuuuuh, that just shows how very biased he is” I hear the chiro community shout. Well let’s put my hypothesis to the test. Here is a complete list of recent (2013)Medline-listed articles on chiropractic; no omission, no bias, just facts (for clarity, the Pubmed-link is listed first, then the title in bold followed by a short comment in italics):
Towards establishing an occupational threshold for cumulative shear force in the vertebral joint – An in vitro evaluation of a risk factor for spondylolytic fractures using porcine specimens.
This is an interesting study of the shear forces observed in porcine vertebral specimen during maneuvers which might resemble spinal manipulation in humans. The authors conclude that “Our investigation suggested that pars interarticularis damage may begin non-linearly accumulating with shear forces between 20% and 40% of failure tolerance (approximately 430 to 860N”
Development of an equation for calculating vertebral shear failure tolerance without destructive mechanical testing using iterative linear regression.
This is a mathematical modelling of the forces that might act on the spine during manipulation. The authors draw no conclusions.
Collaborative Care for Older Adults with low back pain by family medicine physicians and doctors of chiropractic (COCOA): study protocol for a randomized controlled trial.
This is merely the publication of a trial that is about to commence.
Military Report More Complementary and Alternative Medicine Use than Civilians.
This is a survey which suggests that ~45% of all military personnel use some form of alternative medicine.
Complementary and Alternative Medicine Use by Pediatric Specialty Outpatients
This is another survey; it concludes that ” that CAM use is high among pediatric specialty clinic outpatients”
Extending ICPC-2 PLUS terminology to develop a classification system specific for the study of chiropractic encounters
This is an article on chiropractic terminology which concludes that “existing ICPC-2 PLUS terminology could not fully represent chiropractic practice, adding terms specific to chiropractic enabled coding of a large number of chiropractic encounters at the desired level. Further, the new system attempted to record the diversity among chiropractic encounters while enabling generalisation for reporting where required. COAST is ongoing, and as such, any further encounters received from chiropractors will enable addition and refinement of ICPC-2 PLUS (Chiro)”.
US Spending On Complementary And Alternative Medicine During 2002-08 Plateaued, Suggesting Role In Reformed Health System
This is a study of the money spent on alternative medicine concluding as follows “Should some forms of complementary and alternative medicine-for example, chiropractic care for back pain-be proven more efficient than allopathic and specialty medicine, the inclusion of complementary and alternative medicine providers in new delivery systems such as accountable care organizations could help slow growth in national health care spending”
A Royal Chartered College joins Chiropractic & Manual Therapies.
This is a short comment on the fact that a chiro institution received a Royal Charter.
Exposure-adjusted incidence rates and severity of competition injuries in Australian amateur taekwondo athletes: a 2-year prospective study.
This is a study by chiros to determine the frequency of injuries in taekwondo athletes.
The first thing that strikes me is the paucity of articles; ok, we are talking of just january 2013 but by comparison most medical fields like neurology, rheumatology have produced hundreds of articles during this period and even the field of acupuncture research has generated about three times more.
The second and much more important point is that I fail to see much chiropractic research that is truly meaningful or tells us anything about what I consider the most urgent questions in this area, e.g. do chiropractic interventions work? are they safe?
My last point is equally critical. After reading the 9 papers, I have to honestly say that none of them impressed me in terms of its scientific rigor.
So, what does this tiny investigation suggest? Not a lot, I have to admit, but I think it supports the hypothesis that research into chiropractic is not very active, nor high quality, nor does it address the most urgent questions.
Musculoskeletal and rheumatic conditions, often just called “arthritis” by lay people, bring more patients to alternative practitioners than any other type of disease. It is therefore particularly important to know whether alternative medicines (AMs) demonstrably generate more good than harm for such patients. Most alternative practitioners, of course, firmly believe in what they are doing. But what does the reliable evidence show?
To find out, ‘Arthritis Research UK’ has sponsored a massive project lasting several years to review the literature and critically evaluate the trial data. They convened a panel of experts (I was one of them) to evaluate all the clinical trials that are available in 4 specific clinical areas. The results for those forms of AM that are to be taken by mouth or applied topically have been published some time ago, now the report, especially written for lay people, on those treatments that are practitioner-based has been published. It covers the following 25 modalities:
Chiropractic (spinal manipulation)
Kinesiology (applied kinesiology)
Magnet therapy (static magnets)
Osteopathy (spinal manipulation)
Qigong (internal qigong)
Our findings are somewhat disappointing: only very few treatments were shown to be effective.
In the case of rheumatoid arthritis, 24 trials were included with a total of 1,500 patients. The totality of this evidence failed to provide convincing evidence that any form of AM is effective for this particular condition.
For osteoarthritis, 53 trials with a total of ~6,000 patients were available. They showed reasonably sound evidence only for two treatments: Tai chi and acupuncture.
Fifty trials were included with a total of ~3,000 patients suffering from fibromyalgia. The results provided weak evidence for Tai chi and relaxation-therapies, as well as more conclusive evidence for acupuncture and massage therapy.
Low back pain had attracted more research than any of the other diseases: 75 trials with ~11,600 patients. The evidence for Alexander Technique, osteopathy and relaxation therapies was promising by not ultimately convincing, and reasonably good evidence in support of yoga and acupuncture was also found.
The majority of the experts felt that the therapies in question did not frequently cause harm, but there were two important exceptions: osteopathy and chiropractic. For both, the report noted the existence of frequent yet mild, as well as serious but rare adverse effects.
As virtually all osteopaths and chiropractors earn their living by treating patients with musculoskeletal problems, the report comes as an embarrassment for these two professions. In particular, our conclusions about chiropractic were quite clear:
There are serious doubts as to whether chiropractic works for the conditions considered here: the trial evidence suggests that it’s not effective in the treatment of fibromyalgia and there’s only little evidence that it’s effective in osteoarthritis or chronic low back pain. There’s currently no evidence for rheumatoid arthritis.
Our point that chiropractic is not demonstrably effective for chronic back pain deserves some further comment, I think. It seems to be in contradiction to the guideline by NICE, as chiropractors will surely be quick to point out. How can this be?
One explanation is that, since the NICE-guidelines were drawn up, new evidence has emerged which was not positive. The recent Cochrane review, for instance, concludes that spinal manipulation “is no more effective for acute low-back pain than inert interventions, sham SMT or as adjunct therapy”
Another explanation could be that the experts on the panel writing the NICE-guideline were less than impartial towards chiropractic and thus arrived at false-positive or over-optimistic conclusions.
Chiropractors might say that my presence on the ‘Arthritis Research’-panel suggests that we were biased against chiropractic. If anything, the opposite is true: firstly, I am not even aware of having a bias against chiropractic, and no chiropractor has ever demonstrated otherwise; all I ever aim at( in my scientific publications) is to produce fair, unbiased but critical assessments of the existing evidence. Secondly, I was only one of a total of 9 panel members. As the following list shows, the panel included three experts in AM, and most sceptics would probably categorise two of them (Lewith and MacPherson) as being clearly pro-AM:
Professor Michael Doherty – professor of rheumatology, University of Nottingham
Professor Edzard Ernst – emeritus professor of complementary medicine, Peninsula Medical School
Margaret Fisken – patient representative, Aberdeenshire
Dr Gareth Jones (project lead) – senior lecturer in epidemiology, University of Aberdeen
Professor George Lewith – professor of health research, University of Southampton
Dr Hugh MacPherson – senior research fellow in health sciences, University of York
Professor Gary Macfarlane (chair of committee) – professor of epidemiology, University of Aberdeen
Professor Julius Sim – professor of health care research, Keele University
Jane Tadman – representative from Arthritis Research UK, Chesterfield
What can we conclude from all that? I think it is safe to say that the evidence for practitioner-based AMs as a treatment of the 4 named conditions is disappointing. In particular, chiropractic is not a demonstrably effective therapy for any of them. This, of course begs the question, for what condition is chiropractic proven to work! I am not aware of any, are you?
The question whether spinal manipulation is an effective treatment for infant colic has attracted much attention in recent years. The main reason for this is, of course, that a few years ago Simon Singh had disclosed in a comment that the British Chiropractic Association (BCA) was promoting chiropractic treatment for this and several other childhood condition on their website. Simon famously wrote “they (the BCA) happily promote bogus treatments” and was subsequently sued for libel by the BCA. Eventually, the BCA lost the libel action as well as lots of money, and the entire chiropractic profession ended up with enough egg on their faces to cook omelets for all their patients.
At the time, the BCA had taken advice from several medical and legal experts; one of their medical advisers, I was told, was Prof George Lewith. Intriguingly, he and several others have just published a Cochrane review of manipulative therapies for infant colic. Here are the unabbreviated conclusions from their article:
“The studies included in this meta-analysis were generally small and methodologically prone to bias, which makes it impossible to arrive at a definitive conclusion about the effectiveness of manipulative therapies for infantile colic. The majority of the included trials appeared to indicate that the parents of infants receiving manipulative therapies reported fewer hours crying per day than parents whose infants did not, based on contemporaneous crying diaries, and this difference was statistically significant. The trials also indicate that a greater proportion of those parents reported improvements that were clinically significant. However, most studies had a high risk of performance bias due to the fact that the assessors (parents) were not blind to who had received the intervention. When combining only those trials with a low risk of such performance bias, the results did not reach statistical significance. Further research is required where those assessing the treatment outcomes do not know whether or not the infant has received a manipulative therapy. There are inadequate data to reach any definitive conclusions about the safety of these interventions”
Cochrane reviews also carry a “plain language” summary which might be easier to understand for lay people. And here are the conclusions from this section of the review:
The studies involved too few participants and were of insufficient quality to draw confident conclusions about the usefulness and safety of manipulative therapies. Although five of the six trials suggested crying is reduced by treatment with manipulative therapies, there was no evidence of manipulative therapies improving infant colic when we only included studies where the parents did not know if their child had received the treatment or not. No adverse effects were found, but they were only evaluated in one of the six studies.
If we read it carefully, this article seems to confirm that there is no reliable evidence to suggest that manipulative therapies are effective for infant colic. In the analyses, the positive effect disappears, if the parents are properly blinded; thus it is due to expectation or placebo. The studies that seem to show a positive effect are false positive, and spinal manipulation is, in fact, not effective.
The analyses disclose another intriguing aspect: most trials failed to mention adverse effects. This confirms the findings of our own investigation and amounts to a remarkable breach of publication ethics (nobody seems to be astonished by this fact; is it normal that chiropractic researchers ignore generally accepted rules of ethics?). It also reflects badly on the ability of the investigators of the primary studies to be objective. They seem to aim at demonstrating only the positive effects of their intervention; science is, however, not about confirming the researchers’ prejudices, it is about testing hypotheses.
The most remarkable thing about the new Cochrane review is, I think, the in-congruence of the actual results and the authors’ conclusion. To a critical observer, the former are clearly negative but the latter sound almost positive. I think this begs the question about the possibility of reviewer bias.
We have recently discussed on this blog whether reviews by one single author are necessarily biased. The new Cochrane review has 6 authors, and it seems to me that its conclusions are considerably more biased than my single-author review of chiropractic spinal manipulation for infant colic; in 2009, I concluded simply that “the claim [of effectiveness] is not based on convincing data from rigorous clinical trials”.
Which of the two conclusions describe the facts more helpfully and more accurately?
I think, I rest my case.
Even though I have not yet posted a single article on this subject, it already proved to be a most controversial subject in the comments section. A new analysis of the evidence has just been published, and, in view of the news just out of a Royal Charter for the UK College of Chiropractors, it is time to dedicate some real attention to this important issue.
The analysis comes in the form of a systematic review authored by an international team of chiropractors (we should not fear therefore that the authors have an “anti-chiro bias”). Their declared aim was “to determine whether conclusive evidence of a strong association [between neck manipulation and vascular accidents] exists”. The authors make it clear that they only considered case-control studies and omitted all other articles.
They found 4 such publications all of which had methodological limitations. Two studies were of acceptable quality, and one of these studies seemed to show an association between neck manipulation and stroke, while the other one did not. The authors’ conclusion is ambivalent: “Conclusive evidence is lacking for a strong association between neck manipulation and stroke, but it is also lacking for no association”.
The 4 case-control studies, their strength and weaknesses are, of course, well-known and have been discussed several times before. It was also known that the totality of these data fail to provide a clear picture. I would therefore argue that, in such a situation, we need to include further evidence in an attempt to advance the discussion.
Generally speaking, whenever we assess therapeutic safety, we must not ignore case-reports. One might be next to meaningless but collectively they can provide strong indicators of risk. In drug research, for instance, they send invaluable signals about potential problems and many drugs have been withdrawn from the market purely on the basis of case-reports. If we include case-reports in an analysis of the risks of neck manipulations, the evidence generated by the existing case-control studies appears in a very different light. There are virtually hundreds of cases where neck manipulations have seriously injured patients, and many have suffered permanent neurological deficits or worse. Whenever causation is validated by experts who are not chiropractors and thus not burdened with a professional bias, investigators find that most of the criteria for a causal relationship are fulfilled.
While the omission of case-reports in the new review is regrettable, I find many of the staements of the authors helpful and commendable, particularly considering that they are chiropractors. They seem to be aware that, when there is genuine uncertainty, we ought to err on the safe side [the precautionary principle]. Crucially, they comment on the practical implications of our existing knowledge: “Considering this uncertainty, informed consent is warranted for cervical spinal manipulative therapy that advises patients of a possible increase in the risk of a rare form of stroke…” A little later, in their discussion they write: “As the possibility of an association between cervical spinal manipulative therapy and vascular accidents cannot be ruled out, practitioners of cervical spinal manipulative therapy are obliged to take all reasonable steps that aim to minimise the potential risk of stroke. There is evidence that cervical rotation places greater stresses on vertebral arteries than other movements such as lateral flexion, and so it would seem wise to avoid techniques that involve full rotation of the head.”
At this point it is, I think, important to note that UK chiropractors tend not to obtain informed consent from their patients. This is, of course, a grave breach of medical ethics. It becomes even graver, when we consider that the GCC seems to do nothing about it, even though it has been known for many years.
Is this profession really worthy of a Royal Charter? This and the other question raised here require some serious consideration and discussion which, no doubt, will follow this short post.