Cranio-sacral therapy is firstly implausible, and secondly it lacks evidence of effectiveness (see for instance here, here, here and here). Yet, some researchers are nevertheless not deterred to test it in clinical trials. While this fact alone might be seen as embarrassing, the study below is a particular and personal embarrassment to me, in fact, I am shocked by it and write these lines with considerable regret.
Why? Bear with me, I will explain later.
The purpose of this trial was to evaluate the effectiveness of osteopathic manipulative treatment and osteopathy in the cranial field in temporomandibular disorders. Forty female subjects with temporomandibular disorders lasting at least three months were included. At enrollment, subjects were randomly assigned into two groups: (1) osteopathic manipulative treatment group (n=20) and (2) osteopathy in the cranial field [craniosacral therapy for you and me] group (n=20). Examinations were performed at baseline (E0) and at the end of the last treatment (E1), and consisted of subjective pain intensity with the Visual Analog Scale, Helkimo Index and SF-36 Health Survey. Subjects had five treatments, once a week. 36 subjects completed the study.
Patients in both groups showed significant reduction in Visual Analog Scale score (osteopathic manipulative treatment group: p = 0.001; osteopathy in the cranial field group: p< 0.001), Helkimo Index (osteopathic manipulative treatment group: p = 0.02; osteopathy in the cranial field group: p = 0.003) and a significant improvement in the SF-36 Health Survey – subscale “Bodily Pain” (osteopathic manipulative treatment group: p = 0.04; osteopathy in the cranial field group: p = 0.007) after five treatments (E1). All subjects (n = 36) also showed significant improvements in the above named parameters after five treatments (E1): Visual Analog Scale score (p< 0.001), Helkimo Index (p< 0.001), SF-36 Health Survey – subscale “Bodily Pain” (p = 0.001). The differences between the two groups were not statistically significant for any of the three endpoints.
The authors concluded that both therapeutic modalities had similar clinical results. The findings of this pilot trial support the use of osteopathic manipulative treatment and osteopathy in the cranial field as an effective treatment modality in patients with temporomandibular disorders. The positive results in both treatment groups should encourage further research on osteopathic manipulative treatment and osteopathy in the cranial field and support the importance of an interdisciplinary collaboration in patients with temporomandibular disorders. Implications for rehabilitation Temporomandibular disorders are the second most prevalent musculoskeletal condition with a negative impact on physical and psychological factors. There are a variety of options to treat temporomandibular disorders. This pilot study demonstrates the reduction of pain, the improvement of temporomandibular joint dysfunction and the positive impact on quality of life after osteopathic manipulative treatment and osteopathy in the cranial field. Our findings support the use of osteopathic manipulative treatment and osteopathy in the cranial field and should encourage further research on osteopathic manipulative treatment and osteopathy in the cranial field in patients with temporomandibular disorders. Rehabilitation experts should consider osteopathic manipulative treatment and osteopathy in the cranial field as a beneficial treatment option for temporomandibular disorders.
This study has so many flaws that I don’t know where to begin. Here are some of the more obvious ones:
- There is, as already mentioned, no rationale for this study. I can see no reason why craniosacral therapy should work for the condition. Without such a rationale, the study should never even have been conceived.
- Technically, this RCTs an equivalence study comparing one therapy against another. As such it needs to be much larger to generate a meaningful result and it also would require a different statistical approach.
- The authors mislabelled their trial a ‘pilot study’. However, a pilot study “is a preliminary small-scale study that researchers conduct in order to help them decide how best to conduct a large-scale research project. Using a pilot study, a researcher can identify or refine a research question, figure out what methods are best for pursuing it, and estimate how much time and resources will be necessary to complete the larger version, among other things.” It is not normally a study suited for evaluating the effectiveness of a therapy.
- Any trial that compares one therapy of unknown effectiveness to another of unknown effectiveness is a complete and utter nonsense. Equivalent studies can only ever make sense, if one of the two treatments is of proven effectiveness – think of it as a mathematical equation: one equation with two unknowns is unsolvable.
- Controlled studies such as RCTs are for comparing the outcomes of two or more groups, and only between-group differences are meaningful results of such trials.
- The ‘positive results’ which the authors mention in their conclusions are meaningless because they are based on such within-group changes and nobody can know what caused them: the natural history of the condition, regression towards the mean, placebo-effects, or other non-specific effects – take your pick.
- The conclusions are a bonanza of nonsensical platitudes and misleading claims which do not follow from the data.
As regular readers of this blog will doubtlessly have noticed, I have seen plenty of similarly flawed pseudo-research before – so, why does this paper upset me so much? The reason is personal, I am afraid: even though I do not know any of the authors in person, I know their institution more than well. The study comes from the Department of Physical Medicine and Rehabilitation, Medical University of Vienna, Austria. I was head of this department before I left in 1993 to take up the Exeter post. And I had hoped that, even after 25 years, a bit of the spirit, attitude, knowhow, critical thinking and scientific rigor – all of which I tried so hard to implant in my Viennese department at the time – would have survived.
Perhaps I was wrong.
Some of you will remember the saga of the British Chiropractic Association suing my friend and co-author Simon Singh (eventually losing the case, lots of money and all respect). One of the ‘hot potatoes’ in this case was the question whether chiropractic is effective for infant colic. This question is settled, I thought: IT HAS NOT BEEN SHOWN TO WORK BETTER THAN A PLACEBO.
Yet manipulators have not forgotten the defeat and are still plotting, it seems, to overturn it. Hence a new systematic review assessed the effect of manual therapy interventions for healthy but unsettled, distressed and excessively crying infants.
The authors reviewed published peer-reviewed primary research articles in the last 26 years from nine databases (Medline Ovid, Embase, Web of Science, Physiotherapy Evidence Database, Osteopathic Medicine Digital Repository , Cochrane (all databases), Index of Chiropractic Literature, Open Access Theses and Dissertations and Cumulative Index to Nursing and Allied Health Literature). The inclusion criteria were: manual therapy (by regulated or registered professionals) of unsettled, distressed and excessively crying infants who were otherwise healthy and treated in a primary care setting. Outcomes of interest were: crying, feeding, sleep, parent-child relations, parent experience/satisfaction and parent-reported global change. The authors included the following types of peer-reviewed studies in our search: RCTs, prospective cohort studies, observational studies, case–control studies, case series, questionnaire surveys and qualitative studies.
Nineteen studies were selected for full review: seven randomised controlled trials, seven case series, three cohort studies, one service evaluation study and one qualitative study. Only 5 studies were rated as high quality: four RCTs (low risk of bias) and a qualitative study.
The authors found moderate strength evidence for the effectiveness of manual therapy on: reduction in crying time (favourable: -1.27 hours per day (95% CI -2.19 to -0.36)), sleep (inconclusive), parent-child relations (inconclusive) and global improvement (no effect).
Reduction in crying: RCTs mean difference.
The risk of reported adverse events was low (only 8 studies mentioned adverse effects at all, meaning that the rest were in breach of research and publication ethics): seven non-serious events per 1000 infants exposed to manual therapy (n=1308) and 110 per 1000 in those not exposed.
The authors concluded that some small benefits were found, but whether these are meaningful to parents remains unclear as does the mechanisms of action. Manual therapy appears relatively safe.
For several reasons, I find this review, although technically sound, quite odd.
Why review uncontrolled data when RCTs are available?
How can a qualitative study be rated as high quality for assessing the effectiveness of a therapy?
How can the authors categorically conclude that there were benefits when there were only 4 RCTs of high quality?
Why do they not explain the implications of none of the RCTs being placebo-controlled?
How can anyone pool the results of all types of manual therapies which, as most of us know, are highly diverse?
How can the authors conclude about the safety of manual therapies when most trials failed to report on this issue?
Why do they not point out that this is unethical?
My greatest general concern about this review is the overt lack of critical input. A systematic review is not a means of promoting an intervention but of critically assessing its value. This void of critical thinking is palpable throughout the paper. In the discussion section, for instance, the authors state that “previous systematic reviews from 2012 and 2014 concluded there was favourable but inconclusive and weak evidence for manual therapy for infantile colic. They mention two reviews to back up this claim. They conveniently forget my own review of 2009 (the first on this subject). Why? Perhaps because it did not fit their preconceived ideas? Here is my abstract:
Some chiropractors claim that spinal manipulation is an effective treatment for infant colic. This systematic review was aimed at evaluating the evidence for this claim. Four databases were searched and three randomised clinical trials met all the inclusion criteria. The totality of this evidence fails to demonstrate the effectiveness of this treatment. It is concluded that the above claim is not based on convincing data from rigorous clinical trials.
Towards the end of their paper, the authors state that “this was a comprehensive and rigorously conducted review…” I beg to differ; it turned out to be uncritical and biased, in my view. And at the very end of the article, we learn a possible reason for this phenomenon: “CM had financial support from the National Council for Osteopathic Research from crowd-funded donations.”
This is a fascinating new review of upper neck manipulation. It raises many concerns that we, on this blog, have been struggling with for years. I take the liberty of quoting a few passages which I feel are important and encourage everyone to study the report in full:
The Minister of Health, Seniors and Active Living gave direction to the Health Professions Advisory Council (“the Council”) to undertake a review related to high neck manipulation.
Specifically, the Minister directed the Council to undertake:
1) A review of the status of the reserved act in other Canadian jurisdictions,
2) A literature review related to the benefits to patients and risks to patient safety associated with the procedure, and
3) A jurisprudence review or a review into the legal issues that have arisen in Canada with respect to the performance of the procedure that touch upon the risk of harm to a patient.
In addition, the Minister requested the Council to seek written input on the issue from:
- Manitoba Chiropractic Stroke Survivors
- Manitoba Chiropractic Association
- College of Physiotherapists of Manitoba
- Manitoba Naturopathic Association
- College of Physicians and Surgeons of Manitoba
- other relevant interested parties as determined by the Council
… The review indicated that further research is required to:
- strengthen evidence for the efficacy of cervical spinal manipulations (CSM) as a treatment for neck pain and headache, “as well as for other indications where evidence currently does not exist (i.e., upper back and should/arm pain, high blood pressure, etc.)”
- establish safety and efficacy of CSM in infants and children
- assess the risk versus benefit in consideration of using HVLA cervical spine manipulation, which also involve cost-benefit analyses that compare CSM to other standard treatments.
… the performance of “high neck manipulation” or cervical spine manipulation does present a risk of harm to patients. This risk of harm must be understood by both the patient and the practitioner.
Both the jurisprudence review and the research literature review point to the need for the following actions to mitigate the risk of harm associated with the performance of cervical spine manipulation:
- Action One: Ensure that the patient provides written informed consent prior to initiating treatment which includes a discussion about the risk associated with cervical spine manipulation.
- Action Two: Provide patients with information to assist in the early recognition of a serious adverse event.
The British press recently reported that a retired bank manager (John Lawler, aged 80) died after visiting a chiropractor in York. This tragic case was published in multiple articles, most recently in THE SUN. Personally, I find this regrettable – not the fact that the press warns consumers of chiropractic, but the tone and content of the articles.
Let me explain this by citing the one in THE SUN of today. Here is the critical bit that concerns me:
Ezvard Ernst, Emeritus Professor of Complementary Medicine at Exeter University, published a study showing at least 26 people had died as a result. He said: “The evidence is not in favour of chiropractic treatments. Nobody knows how many have suffered severe complications or died.” Edvard Ernst, Professor of Complementary Medicine, says many have suffered complications or died from chiropractors treatments… A study from Exeter University shows at least 26 people have died as a result of treatment.
And what is wrong with this?
The answer is lots:
- My first name is consistently misspelled (a triviality, I agree).
- I am once named as Emeritus Professor and once as Professor of Complementary Medicine. The latter is wrong (another triviality, perhaps, but some of my more demented critics have regularly accused me of carrying wrong titles)
- The mention of 26 deaths after chiropractic treatments is problematic and arguably misleading (see below).
- Our ‘study’ was not a study but a systematic review (another triviality?).
Now you probably think I am being pedantic, but I feel that the article is regrettable not so much by what it says but by what it fails to say. To understand this better, I will below copy my emails to the journalist who asked for help in researching this article.
- My email of 17/10 answering all 7 of the journalist’s specific questions:
- 1. Why are you sceptical of chiropractic?
- I have researched the subject for more than 2 decades, and I know that the evidence is not in favour of chiropractic
- 2. How many people do you believe have died in Britain as a result of being treated by a chiropractor? If it’s not possible to say, can you estimate?
- nobody knows how many patients have suffered severe complications or deaths. there is no system to monitor such events that is comparable to the post-marketing surveillance of conventional medicine. we did some research and found that the under-reporting of cases of severe complications was close to 100% in the UK.
- 3. What is so dangerous about chiropractic? Is there a particular physical treatment than endangers life?
- manipulations that involve rotation and over-extension of the upper spine can lead to a vertebral artery breaking up. this causes a stroke which sometimes is fatal.
- 4. Is the industry well regulated?
- UK chiropractors are regulated by the General Chiropractic Council. it is debatable whether they are fit for purpose (see here:http://edzardernst.com/2015/02/the-uk-general-chiropractic-council-fit-for-purpose/)
- 5. Should we be suspicious of claims that chiropractic can cure things like IBS and autism?
- such claims are not based on good evidence and therefore misleading and unethical. sadly, however, they are prevalent.
- 6. Who trains chiropractors?
- there are numerous colleges that specialise in that activity.
- 7. Is it true Prince Charles is to blame for the rise in popularity/prominence of chiropractic?
- I am not sure. certainly he has been promoting all sorts of unproven treatments for decades.
- My email of 18/10 answering 3 further specific questions
- 1. Would you actively discourage anyone from being treated by a chiropractor?
yes, anyone I feel responsible for
2. Are older people particularly at risk or could one wrong move affect anyone?
older people are at higher risk of bone fractures and might also have more brittle arteries prone to dissection
3. If someone has, say, a bad back or stiff neck what treatment would you recommend instead of chiropractic?
I realise every case is different, but you are sceptical of all complementary treatments (as I understand it) so what would you suggest instead?
I would normally consider therapeutic exercises and recommend seeing a good physio.
- 3. My email of 23/10 replying to his request for specific UK cases
- the only thing I can offer is this 2001 paper
- where we discovered 35 cases seen by UK neurologists within the preceding year. the truly amazing finding here was that NONE of them had been reported anywhere before. this means under-reporting was exactly 100%.
END OF QUOTES
I think that makes it quite obvious that much relevant information never made it into the final article. I also know that several other experts provided even more information than I did which never appeared.
The most important issues, I think, are firstly the lack of a monitoring system for adverse events, secondly the level of under-reporting and thirdly the 50% rate of mild to moderate adverse-effects. Without making these issues amply clear, lay readers cannot possibly make any sense of the 26 deaths. More importantly, chiropractors will now be able to respond by claiming: 26 deaths compare very favourably with the millions of fatalities caused by conventional medicine. In the end, the message that will remain in the heads of many consumers is this: CONVENTIONAL MEDICINE IS MUCH MORE DANGEROUS THAN CHIROPRACTIC!!! (The 1st comment making this erroneous point has already been published: Don’t be stupid Andy. You wanna discuss how many deaths occur due to medication side effects and drug interactions? There is a reason chiros have the lowest malpractice rates.)
Don’t get me wrong, I am not accusing the author of the SUN-article. For all I know, he has filed a very thoughtful and complete piece. It might have been shortened by the editor who may also have been the one adding the picture of the US starlet with her silicone boobs. But I am accusing THE SUN of missing a chance to publish something that might have had the chance of being a meaningful contribution to public health.
Perhaps you still think this is all quite trivial. Yet, after having experienced this sort of thing dozens, if not hundreds of times, I disagree.
Systematic reviews are aimed at summarising and critically evaluating the evidence on a specific research question. They are the highest level of evidence and are more reliable than anything else we have. Therefore, they represent a most useful tool for both clinicians and researchers.
But there are, of course, exceptions. Take, for instance, this recent systematic review by researchers from the
- Texas Chiropractic College, Pasadena, the Palmer Center for Chiropractic Research, Palmer College of Chiropractic, Davenport,
- Department of Planning, Policy and Design, University of California, Irvine,
- VA Puget Sound Health Care System, Tacoma,
- New York Chiropractic College, Seneca Falls,
- Logan University College of Chiropractic, Chesterfield,
- University of Western States, Portland.
The new guidelines by the American College of Physicians entitled ‘Noninvasive Treatments for Acute, Subacute, and Chronic Low Back Pain: A Clinical Practice Guideline From the American College of Physicians’ have already been the subject of the previous post. Today, I want to have a closer look at a small section of these guidelines which, I think, is crucial. It is entitled ‘HARMS OF NONPHARMACOLOGIC THERAPIES’. I have taken the liberty of copying it below:
“Evidence on adverse events from the included RCTs and systematic reviews was limited, and the quality of evidence for all available harms data is low. Harms were poorly reported (if they were reported at all) for most of the interventions.
Low-quality evidence showed no reported harms or serious adverse events associated with tai chi, psychological interventions, multidisciplinary rehabilitation, ultrasound, acupuncture, lumbar support, or traction (9,95,150,170–174). Low-quality evidence showed that when harms were reported for exercise, they were often related to muscle soreness and increased pain, and no serious harms were reported. All reported harms associated with yoga were mild to moderate (119). Low-quality evidence showed that none of the RCTs reported any serious adverse events with massage, although 2 RCTs reported soreness during or after massage therapy (175,176). Adverse events associated with spinal manipulation included muscle soreness or transient increases in pain (134). There were few adverse events reported and no clear differences between MCE and controls. Transcutaneous electrical nerve stimulation was associated with an increased risk for skin site reaction but not serious adverse events (177). Two RCTs (178,179) showed an increased risk for skin flushing with heat compared with no heat or placebo, and no serious adverse events were reported. There were no data on cold therapy. Evidence was insufficient to determine harms of electrical muscle stimulation, LLLT, percutaneous electrical nerve stimulation, interferential therapy, short-wave diathermy, and taping.”
The first thing that strikes me is the brevity of the section. Surely, guidelines of this nature must include a full discussion of the risks of the treatments in question!
The second thing that is noteworthy is the fact that the authors confirm the fact I have been banging on about for years: clinical trials of alternative therapies far too often fail to mention adverse effects. I have often pointed out that the failure to report adverse effects in clinical trials is an unacceptable violation of medical ethics. By contrast, the guideline authors seem not to feel strongly about this omission.
The third thing that is noteworthy is that the guidelines evaluate the harms of the treatments purely on the basis of the adverse effects reported in the clinical trials and systematic reviews included in their efficacy assessments. This is nonsensical for at least two reasons:
- The guideline authors themselves are aware that the trials very often fail to mention adverse effects.
- For any assessment of harm, one has to go far beyond the evidence of clinical trials, because trials tend to be too small to pick up rare adverse effects, and because they are always conducted under optimally controlled conditions where adverse effects are less likely to occur than in real life.
Together, these features of the assessment of harms explain why the guideline authors arrive at conclusions which are oddly misguided; I would even feel that they resemble a white-wash. Here are two of the most overt misjudgements:
- no harms associated with acupuncture,
- only trivial harm associated with spinal manipulations.
The best evidence we have today shows that acupuncture leads to mild adverse effects in about 10% of all cases and is also associated with very severe complications (e.g. pneumothorax, cardiac tamponade, infections, deaths) in an unknown number of patients. More details can be found for instance here, here, here and here.
And the best evidence available shows that spinal manipulation leads to moderately severe adverse effects in ~50% of all cases. In addition, we know of hundreds of cases of very severe complications resulting in stroke, permanent neurological deficits or deaths. More details can be found for instance here, here, here and here.
In the introduction, I stated that this small section of the guidelines is crucial.
The reason is simple: any responsible therapeutic decision has to be based not just on the efficacy of the treatment in question but on its risk/benefit balance. The evidence shows that the risks of some alternative therapies can be considerable, a fact that is almost totally neglected in the guidelines. Therefore, the recommendations of the new guidelines by the American College of Physicians entitled ‘Noninvasive Treatments for Acute, Subacute, and Chronic Low Back Pain: A Clinical Practice Guideline From the American College of Physicians’ are in several aspects not entirely correct and need to be reconsidered.
The question whether spinal manipulative therapy (SMT) is effective for acute low back pain is still discussed controversially. Chiropractors (they use SMT more regularly than other professionals) try everything to make us believe it does work, while the evidence is far less certain. Therefore, it is worth considering the best and most up-to-date data.
The aim of this paper was to systematically review studies of the effectiveness and harms of SMT for acute (≤6 weeks) low back pain. The research question was straight forward: Is the use of SMT in the management of acute (≤6 weeks) low back pain associated with improvements in pain or function?
A through literature search was conducted to locate all relevant papers. Study quality was assessed using the Cochrane Back and Neck (CBN) Risk of Bias tool. The evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria. The main outcome measures were pain (measured by either the 100-mm visual analog scale, 11-point numeric rating scale, or other numeric pain scale), function (measured by the 24-point Roland Morris Disability Questionnaire or Oswestry Disability Index [range, 0-100]), or any harms measured within 6 weeks.
Of 26 eligible RCTs identified, 15 RCTs (1711 patients) provided moderate-quality evidence that SMT has a statistically significant association with improvements in pain (pooled mean improvement in the 100-mm visual analog pain scale, −9.95 [95% CI, −15.6 to −4.3]). Twelve RCTs (1381 patients) produced moderate-quality evidence that SMT has a statistically significant association with improvements in function (pooled mean effect size, −0.39 [95% CI, −0.71 to −0.07]). Heterogeneity was not explained by type of clinician performing SMT, type of manipulation, study quality, or whether SMT was given alone or as part of a package of therapies. No RCT reported any serious adverse event. Minor transient adverse events such as increased pain, muscle stiffness, and headache were reported 50% to 67% of the time in large case series of patients treated with SMT.
The authors concluded that among patients with acute low back pain, spinal manipulative therapy was associated with modest improvements in pain and function at up to 6 weeks, with transient minor musculoskeletal harms. However, heterogeneity in study results was large.
This meta-analysis has been celebrated by chiropractors around the world as a triumph for their hallmark therapy, SMT. But there have also been more cautionary voices – not least from the lead author of the paper. Patients undergoing spinal manipulation experienced a decline of 1 point in their pain rating, says Dr. Paul Shekelle, an internist with the West Los Angeles Veterans Affairs Medical Center and the Rand Corporation who headed the study. That’s about the same amount of pain relief as from NSAIDs, over-the-counter nonsteroidal anti-inflammatory medication, such as ibuprofen. The study also found spinal manipulation modestly improved function. On average, patients reported greater ease and comfort engaging in two day-to-day activities — such as finding they could walk more quickly, were having less difficulty turning over in bed or were sleeping more soundly.
It’s not clear exactly how spinal manipulation relieves back pain. But it may reposition the small joints in the spine in a way that causes less pain, according to Dr. Richard Deyo, an internist and professor of evidence-based medicine at the Oregon Health and Science University. Deyo wrote an editorial published along with the study. Another possibility, Deyo says, is that spinal manipulation may restore some material in the disk between the vertebrae, or it may simply relax muscles, which could be important. There may also be mind-body interaction that comes from the “laying of hands” or a trusting relationship between patients and their health care provider, he says.
Deyo notes that there are many possible treatments for lower back pain, including oral medicine, injected medicine, corsets, traction, surgery, acupuncture and massage therapy. But of about 200 treatment options, “no single treatment is clearly superior,” he says.
In another comment by Paul Ingraham the critical tone was much clearer: “Claiming it as a victory is one of the best examples I’ve ever seen of making lemonade out of science lemons! But I can understand the mistake, because the review itself does seem positive at first glance: the benefits of SMT are disingenuously summarized as “statistically significant” in the abstract, with no mention of clinical significance (effect size; see Statistical Significance Abuse). So the abstract sounds like good news to anyone but the most wary readers, while deep in the main text the same results are eventually conceded to be “clinically modest.” But even even that seems excessively generous: personally, I need at least a 2-point improvement in pain on a scale of 10 to consider it a “modest” improvement! This is not a clearly positive review: it shows weak evidence of minor efficacy, based on “significant unexplained heterogeneity” in the results. That is, the results were all over the place — but without any impressive benefits reported by any study — and the mixture can’t be explained by any obvious, measurable factor. This probably means there’s just a lot of noise in the data, too many things that are at least as influential as the treatment itself. Or — more optimistically — it could mean that SMT is “just” disappointingly mediocre on average, but might have more potent benefits in a minority of cases (that no one seems to be able to reliably identify). Far from being good news, this review continues a strong trend (eg Rubinstein 2012) of damning SMT with faint praise, and also adds evidence of backfiring to mix. Although fortunately “no RCT reported any serious adverse event,” it seems that minor harms were legion: “increased pain, muscle stiffness, and headache were reported 50% to 67% of the time in large case series of patients treated with SMT.” That’s a lot of undesirable outcomes. So the average patient has a roughly fifty-fifty chance of up to roughly maybe a 20% improvement… or feeling worse to some unknown degree! That does not sound like a good deal to me. It certainly doesn’t sound like good medicine.”
END OF QUOTE
As I have made clear in many previous posts, I do fully agree with these latter statements and would add just three points:
- We know that many of the SMT studies completely neglect reporting adverse effects. Therefore it is hardly surprising that no serious complications were on record. Yet, we know that they do occur with sad regularity.
- None of the studies controlled for placebo effects. It is therefore possible – I would say even likely – that a large chunk of the observed benefit is not due to SMT per se but to a placebo response.
- It seems more than questionable whether the benefits of SMT outweigh its risks.
Is spinal manipulative therapy (SMT) dangerous? This question has kept us on this blog busy for quite some time now. To me, there is little doubt that SMT can cause adverse effects some of which are serious. But many chiropractors seem totally unconvinced. Perhaps this new overview of reviews might help to clarify the issue. Its aim was to elucidate and quantify the risk of serious adverse events (SAEs) associated with SMT.
The authors searched five electronic databases from inception to December 8, 2015 and included reviews on any type of studies, patients, and SMT technique. The primary outcome was SAEs. The quality of the included reviews was assessed using a measurement tool to assess systematic reviews (AMSTAR). Since there were insufficient data for calculating incidence rates of SAEs, they used an alternative approach; the conclusions regarding safety of SMT were extracted for each review, and the communicated opinion were judged by two reviewers independently as safe, harmful, or neutral/unclear. Risk ratios (RRs) of a review communicating that SMT is safe and meeting the requirements for each AMSTAR item, were calculated.
A total of 283 eligible reviews were identified, but only 118 provided data for synthesis. The most frequently described adverse events (AEs) were stroke, headache, and vertebral artery dissection. Fifty-four reviews (46%) expressed that SMT is safe, 15 (13%) expressed that SMT is harmful, and 49 reviews (42%) were neutral or unclear. Thirteen reviews reported incidence estimates for SAEs, roughly ranging from 1 in 20,000 to 1 in 250,000,000 manipulations. Low methodological quality was present, with a median of 4 of 11 AMSTAR items met (interquartile range, 3 to 6). Reviews meeting the requirements for each of the AMSTAR items (i.e. good internal validity) had a higher chance of expressing that SMT is safe.
The authors concluded that it is currently not possible to provide an overall conclusion about the safety of SMT; however, the types of SAEs reported can indeed be significant, sustaining that some risk is present. High quality research and consistent reporting of AEs and SAEs are needed.
This article is valuable, if only for the wealth of information one can extract from it. There are, however, numerous problems. One is that the overview included mostly reviews of the effectiveness of SMT for various conditions. We know that studies of SMT often do not even mention AEs. If such studies are then pooled in a review, they inevitably generate an impression of safety. But this would, of course, be a false-positive result!
The authors of the overview are aware of this problem and address it in the following paragraph: “When only considering the subset of reviews, where the objective was to investigate AEs (37 reviews), then 8 reviews (22%) expressed that SMT is safe, 13 reviews (35%) expressed that SMT is harmful and 16 reviews (43%) were neutral or unclear regarding the safety of SMT. Hence, there is a tendency that a bigger proportion of these reviews are expressing that SMT is harmful compared to the full sample of reviews…”
To my surprise, I found several of my own reviews in the ‘neutral or unclear’ category. Here are the verbatim conclusions of three of them:
- It is concluded that serious cerebrovascular complications of spinal manipulation continue to be reported.
- The most common serious adverse events are vertebrobasilar accidents, disk herniation, and cauda equina syndrome.
- These data indicate that mild and transient adverse events seem to be frequent. Serious adverse events are probably rare but their incidence can only be estimated at present.
I find it puzzling how this could be classified as neutral or unclear. The solution of the puzzle might lie in the methodology used: “we appraised the communicated opinions of each review concerning the safety of SMT based on their conclusions regarding the AEs and SAEs. This was done by two reviewers independently (SMN, LK), who judged the communicated opinions as either ‘safe’, ‘neutral/unclear’ or ‘harmful’, based on the qualitative impression the reviewers had when reading the conclusions. The reviewers had no opinion about the safety/harmfulness of SMT before commencing the judgements. Cohen’s weighted Kappa was calculated for the agreement between the reviewers, with a value of 0.40–0.59 indicating ‘fair agreement’, 0.60–0.74 indicating ‘good agreement’ and ≥0.75 indicating ‘excellent agreement’. Disagreements were resolved by a third reviewer (MH).”
In other words, the categorisation was done on the basis of subjective judgements of two researchers. It seems obvious that, if their attitude was favourable towards SMT, their judgements would be influenced. The three examples from my own work cited above indicates to me that their verdicts were indeed far from objective.
So what is the main message here? In my view, it can be summarized in the following quote from the overview: “a bigger proportion of these reviews are expressing that SMT is harmful …”
Yes, yes, yes – I know that, if you are a chiropractor (or other practitioner using mostly SMT), you are unlikely to agree with this!
Perhaps you can agree with this statement then:
As long as there is reasonable doubt about the safety of SMT, and as long as we cannot be sure that SMT generates more good than harm, we should be very cautious using it for routine healthcare and do rigorous research to determine the truth (it’s called the precautionary principle and applies to all types of healthcare).
We have discussed the risks of (chiropractic) spinal manipulation more often than I care to remember. The reason for this is simple: it is an important subject; making sure that as many consumers know about it will save lives, I am sure. Therefore, any new paper on the subject is likely to be reported on this blog.
Objective of this review was to identify characteristics of 1) patients, 2) practitioners, 3) treatment process and 4) adverse events (AE) occurring after cervical spinal manipulation (CSM) or cervical mobilization. Systematic searches were performed in 6 electronic databases. Of the initial 1043 studies, 144 studies were included.
They reported 227 cases. 117 cases described male patients with a mean age of 45 (SD 12) and a mean age of 39 (SD 11) for females. Most patients were treated by chiropractors (66%) followed by non-clinicians (5%), osteopaths (5%), physiotherapists (3%) and other medical professions. Manipulation was reported in 95% of the cases (mobilisations only in 1.7%), and neck pain was the most frequent indication.
Cervical arterial dissection (CAD) was reported in 57% of the cases and 46% had immediate onset symptoms; in 2% onset of symptoms took for more than two weeks. Other complications were disc rupture, spinal cord swelling and thrombus. The most frequently reported symptoms included disturbance of voluntary control of movement, pain, paresis and visual disturbances.
In most of the reports, patient characteristics were described poorly. No clear patient profile, related to the risk of AE after CSM, could be extracted. However, women seem more at risk for CAD.
The authors concluded that there seems to be under-reporting of cases. Further research should focus on a more uniform and complete registration of AE using standardized terminology.
I do not want to repeat what I have stated in previous posts on this subject. So,let me just ask this simple question: IF THERE WERE A DRUG MARKTED FOR NECK PAIN BUT NOT SUPPORTED BY GOOD EVIDENCE FOR EFFICACY, DO YOU THINK IT WOULD BE ON THE MARKET AFTER 227 CASES OF SEVERE ADVERSE EFFECTS HAD BEEN DESCRIBED?
I think the answer is NO!
If we then consider the huge degree of under-reporting in this area which might bring the true figure up by one or even two dimensions, we must ask: WHY IS CERVICAL MANIPULATION STILL USED?
As has been discussed on this blog many times before, the chiropractic profession seems to be in a bit of a crisis (my attempt at a British understatement). The Australian chiropractor, Bruce Walker, thinks that, with the adoption of his ten point plan, “the chiropractic profession has an opportunity to turn things around within a generation. Importantly, it has an obligation to the public and to successive generations of chiropractors ahead of it. By embracing this plan the profession can be set on a new path, a new beginning and a new direction. This plan should be known as the new chiropractic.”
And now you are. of course, dying to hear this 10 point plan – well, here it is [heavily abbreviated, I am afraid (the footnotes [ ] and the comments referring to them are mine)]:
- There is a need to improve pre professional education for chiropractors.
Universities or private colleges?
Chiropractic education should where possible be conducted at universities  and this does not mean small single purpose institutions that are deemed universities in name only. Why is this recommended? Primarily because unlike some private colleges, government funded universities insist on intellectual evidence based rigour  in their learning and teaching and importantly require staff to be research active. Chiropractic courses need to have an underpinning pedagogy that insists that content  is taught in the context of the evidence  and that students obtain the necessary training to question and critically appraise …
Underpinning chiropractic education is program accreditation and this is also in need of review particularly where vitalistic subluxation  based courses have been legitimised by the accreditation process…
Chiropractic education should also involve specifically relevant hospital access or work experience such as hospital rounds so that students can observe patients that are truly unwell and observe the signs and symptoms taught in their theory classes. Hospital rounds would also allow chiropractic students to interact with other health providers and increase the likelihood of legitimate partnership and respect between health professions .
Who should teach chiropractic students?…
- There is a need to establish a progressive identity.
Chiropractors need to become solely musculoskeletal practitioners with a special emphasis on spinal pain . If the profession becomes the world’s experts in this area it will command the respect deserved . Importantly it will not be seen as a collective of alternative medicine practitioners with a strange belief system …
- The profession should develop a generalised special interest.
…Chiropractic as a profession should also develop a special interest area in the health sciences that can make a worldwide contribution to other related health sciences. This could be either research based or clinically based or indeed both. Some possibilities are: the further development and refinement of evidence based practice , improved posture through motor control, musculoskeletal care for the aged and elderly, improving bone density or the very important area of translating research into practice via implementation science. Whatever chosen we need to develop a special interest that sets us apart as experts in a distinctive area .
- Marginalisation of the nonsensical elements within the profession.
As professionals chiropractors should not tolerate colleagues or leadership in the profession who demonstrate aberrant ideas. If colleagues transgress the boundaries or professionalism they should be reported to authorities and this should be followed up with action by those authorities …
- The profession and individual practitioners should be pro public health.
It is important to speak up openly in favour of evidence-based public health measures and to join public health associations and agencies … For example, chiropractors promoting anti-vaccination views need to be countered …
- Support legitimate organised elements of the profession.
Practitioners should support and become involved in chiropractic organisations that are clearly ethical and evidence based  and add value to them…
…Regular collective professional advertising of the benefits of chiropractic for back pain, for example, is a worthy undertaking but the advertisements or media offerings must be evidence based .
- The profession should strive to improve clinical practice.
Chiropractors contribute to the public health by the aggregated benefit of positive outcomes to health from their clinical practices … Where restrictive practice laws relating to chiropractors prescribing medication exist the profession should seek to overturn them …
- The profession should embrace evidence based practice.
EBP is the amalgam of best scientific evidence plus clinical expertise plus patient values and circumstances. So what could be missing from this equation? It is clear that in the opinion of a sizable minority of the profession the elements that are missing are “practitioner ideology” and “practitioner values and circumstances”. These additional self- serving and dangerous notions should not be entertained. The adoption of evidence based practice is critical to the future of chiropractic and yet there is resistance by elements within the profession. Soft resistance occurs with attempts to change the name of “Evidence-based practice” (EBP) to “Evidence-informed practice” (EIP). It is worth noting that currently there are over 13,000 articles listed in PUBMED on EBP but less than 100 listed on EIP. So why are some of our profession so keen to use this alternate and weaker term?
Hard resistance against EBP occurs where it is stated that the best evidence is that based on practice experience and not research. This apparently is known as Practice Based Evidence (PBE) and has a band of followers …
- The profession must support research.Research needs to become the number one aspiration of the profession. Research informs both practice and teaching. Without research the profession will not progress. Sadly, the research contribution by the chiropractic profession can only be described as seed like. Figure 1 is a comparison of articles published in the past 45 years by decade using the key words “Physiotherapy” or “Physical Therapy” versus “Chiropractic” (source PUBMED). The Y axis is the number of articles published and the X axis is the decade, the red represents physiotherapy articles, the blue chiropractic. The difference is stark and needs urgent change .If the profession at large ignores research whether in its conduct, administration or its results the profession will wither on the vine …
- Individual chiropractors need to show personal leadership to effect change.
Change within the profession will likely only occur if individual chiropractors show personal leadership….
As part of this personal leadership it will be critical to speak out within the profession. Speak out and become a mentor to less experienced colleagues …
Anyone you thinks that with such a strategy “the chiropractic profession has an opportunity to turn things around within a generation” is, in my view, naïve and deluded. The 10 points are not realistic and woefully incomplete. The most embarrassing omission is a clear statement that chiropractors are fully dedicated to making sure that they serve the best interest of their patients by doing more good than harm.