MD, PhD, FMedSci, FSB, FRCP, FRCPEd

spinal manipulation

“Dr” Brian Moravec is a chiropractor from the US; he has a website where he describes himself and his skills as follows: I attended Chiropractic College and I am a graduate of Palmer College of Chiropractic in Davenport Iowa. I earned a Bachelor of Science degree as well as my Doctor of Chiropractic degree from Palmer College, which is the first chiropractic college in the world and the origin of our profession. I also attend continuing education seminars designed to keep doctors current with regard to clinical chiropractic, technique and nutrition.

The key to overall health and wellness is to have a healthy nervous system and that is what I do as a chiropractor – I make sure that your spine is functioning at its best so that your nervous system functions at its best. When the nervous system is functioning at 100%, you are a healthier individual that experiences a higher quality of life and health. I know this to be true in myself, my family and my patients.

I go to great lengths to provide my patients with the best chiropractic care I can give. I work with my patients to design a treatment plan that will be effective for their particular condition and specific to their needs. We utilize manual and low force techniques (safe and effective for newborns to seniors), to correct sublaxations in the spine. Chiropractic adjustments remove nerve interference, which allows the body to perform at its best again. I also am available for consultations on nutrition and diet, dietary supplementation and how to minimize the wear and tear on your spine.

[Emphases are mine]

What he does not state is the fact that he also is a nifty e-mail writer!

To my great surprise, I received an e-mail from him which is far too good to be kept for myself. So I decided to share it with my readers; here it is in its full and unabbreviated beauty:

its interesting to see someone with your education, and is a self proclaimed “expert” on alternative medicine, promote so much misinformation with regard to chiropractic care.   fortunately you look old.  and soon will be gone.  I always refer to the few of you anti chiropractic fools left here as “dinosaurs”.   the proof is in the pudding my “friend”.  chiropractic works and will continue to be here for centuries more.   you and others with much much more power than you (the AMA for example) have tried to perpetuate lies and squash chiropractic.  you fail, and they failed, because whatever better serves mankind will stand the test of time.   you’re a dying breed edzard.  thank God.
yours in health,

brian moravec d.c.

I am encouraged to see that he recognises my education but do wonder why his upbringing obviously failed so dismally teach him even a minimum of politeness, tact, or critical thinking. It is disappointing, I think, that he does not even mention what he perceives as my lies about his beloved chiropractic. So sad, I am sure it would have been fun to debate with him.

One of the problems regularly encountered when evaluating the effectiveness of chiropractic spinal manipulation is that there are numerous chiropractic spinal manipulative techniques and clinical trials rarely provide an exact means of differentiating between them. Faced with a negative studies, chiropractors might therefore argue that the result was negative because the wrong techniques were used; therefore they might insist that it does not reflect chiropractic in a wider sense. Others claim that even a substantial body of negative evidence does not apply to chiropractic as a whole because there is a multitude of techniques that have not yet been properly tested. It seems as though the chiropractic profession wants the cake and eat it.

Amongst the most commonly used is the ‘DIVERSIFIED TECHNIQUE’ (DT) which has been described as follows: Like many chiropractic and osteopathic manipulative techniques, Diversified is characterized by a high velocity low amplitude thrust. Diversified is considered the most generic chiropractic manipulative technique and is differentiated from other techniques in that its objective is to restore proper movement and alignment of spine and joint dysfunction.

Also widely used is a technique called ‘FLEXION DISTRACTION’ (FD) which involves the use of a specialized table that gently distracts or stretches the spine and which allows the chiropractor to isolate the area of disc involvement while slightly flexing the spine in a pumping rhythm.

The ‘ACTIVATOR TECHNIQUE’ (AT) seems a little less popular; it involves having the patient lie in a prone position and comparing the functional leg lengths. Often one leg will seem to be shorter than the other. The chiropractor then carries out a series of muscle tests such as having the patient move their arms in a certain position in order to activate the muscles attached to specific vertebrae. If the leg lengths are not the same, that is taken as a sign that the problem is located at that vertebra. The chiropractor treats problems found in this way moving progressively along the spine in the direction from the feet towards the head. The activator is a small handheld spring-loaded instrument which delivers a small impulse to the spine. It was found to give off no more than 0.3 J of kinetic energy in a 3-millisecond pulse. The aim is to produce enough force to move the vertebrae but not enough to cause injury.

There is limited research comparing the effectiveness of these and the many other techniques used by chiropractors, and the few studies that are available are usually less than rigorous and their findings are thus unreliable. A first step in researching this rather messy area would be to determine which techniques are most frequently employed.

The aim of this new investigation was to do just that, namely to provide insight into which treatment approaches are used most frequently by Australian chiropractors to treat spinal musculoskeletal conditions.

A questionnaire was sent online to the members of the two main Australian chiropractic associations in 2013. The participants were asked to provide information on treatment choices for specific spinal musculoskeletal conditions.

A total of 280 responses were received. DT was the first choice of treatment for most of the included conditions. DT was used significantly less in 4 conditions: cervical disc syndrome with radiculopathy and cervical central stenosis were more likely to be treated with AT. FD was used almost as much as DT in the treatment of lumbar disc syndrome with radiculopathy and lumbar central stenosis. More experienced Australian chiropractors use more AT and soft tissue therapy and less DT compared to their less experienced chiropractors. The majority of the responding chiropractors also used ancillary procedures such as soft tissue techniques and exercise prescription in the treatment of spinal musculoskeletal conditions.

The authors concluded that this survey provides information on commonly used treatment choices to the chiropractic profession. Treatment choices changed based on the region of disorder and whether neurological symptoms were present rather than with specific diagnoses. Diversified technique was the most commonly used spinal manipulative therapy, however, ancillary procedures such as soft tissue techniques and exercise prescription were also commonly utilised. This information may help direct future studies into the efficacy of chiropractic treatment for spinal musculoskeletal disorders.

I am a little less optimistic that this information will help to direct future research. Critical readers might have noticed that the above definitions of two commonly used techniques are rather vague, particularly that of DT.

Why is that so? The answer seems to be that even chiropractors are at a loss coming up with a good definition of their most-used therapeutic techniques. I looked hard for a more precise definition but the best I could find was this: Diversified is characterized by the manual delivery of a high velocity low amplitude thrust to restricted joints of the spine and the extremities. This is known as an adjustment and is performed by hand. Virtually all joints of the body can be adjusted to help restore proper range of motion and function. Initially a functional and manual assessment of each joint’s range and quality of motion will establish the location and degree of joint dysfunction. The patient will then be positioned depending on the region being adjusted when a specific, quick impulse will be delivered through the line of the joint in question. The direction, speed, depth and angles that are used are the product of years of experience, practice and a thorough understanding of spinal mechanics. Often a characteristic ‘crack’ or ‘pop’ may be heard during the process. This is perfectly normal and is nothing to worry about. It is also not a guide as to the value or effectiveness of the adjustment.

This means that the DT is not a single method but a hotchpotch of techniques; this assumption is also confirmed by the following quote: The diversified technique is a technique used by chiropractors that is composed of all other techniques. It is the most commonly used technique and primarily focuses on spinal adjustments to restore function to vertebral and spinal problems.

What does that mean for research into chiropractic spinal manipulation? It means, I think, that even if we manage to define that a study was to test the effectiveness of one named chiropractic technique, such as DT, the chiropractors doing the treatments would most likely do what they believe is required for each individual patient.

There is, of course, nothing wrong with that approach; it is used in many other area of health care as well. In such cases, we need to view the treatment as something like a ‘black box'; we test the effectiveness of the black box without attempting to define its exact contents, and we trust that the clinicians in the trial are well-trained to use the optimal mix of techniques as needed for each individual patient.

I would assume that, in most studies available to date, this is precisely what already has been implemented. It is simply not reasonable to assume that a trial the trialists regularly instructed the chiropractors not to use the optimal treatments.

What does that mean for the interpretation of the existing trial evidence? It means, I think, that we should interpret it on face value. The clinical evidence for chiropractic treatment of most conditions fails to be convincingly positive. Chiropractors often counter that such negative findings fail to take into account that chiropractors use numerous different techniques. This argument is not valid because we must assume that in each trial the optimal techniques were administered.

In other words, the chiropractic attempt to have the cake and eat it has failed.

On this blog, I have often pointed out how dismally poor most of the trials of alternative therapies frequently are, particularly those in the realm of chiropractic. A brand-new study seems to prove my point.

The aim of this trial was to determine whether spinal manipulative therapy (SMT) plus home exercise and advice (HEA) compared with HEA alone reduces leg pain in the short and long term in adults with sub-acute and chronic back-related leg-pain (BRLP).

Patients aged 21 years or older with BRLP for least 4 weeks were randomised to receive 12 weeks of SMT plus HEA or HEA alone. Eleven chiropractors with a minimum of 5 years of practice experience delivered SMT in the SMT plus HEA group. The primary outcome was subjective BRLP at 12 and 52 weeks. Secondary outcomes were self-reported low back pain, disability, global improvement, satisfaction, medication use, and general health status at 12 and 52 weeks.

Of the 192 enrolled patients, 191 (99%) provided follow-up data at 12 weeks and 179 (93%) at 52 weeks. For leg pain, SMT plus HEA had a clinically important advantage over HEA (difference, 10 percentage points [95% CI, 2 to 19]; P = 0.008) at 12 weeks but not at 52 weeks (difference, 7 percentage points [CI, -2 to 15]; P = 0.146). Nearly all secondary outcomes improved more with SMT plus HEA at 12 weeks, but only global improvement, satisfaction, and medication use had sustained improvements at 52 weeks. No serious treatment-related adverse events or deaths occurred.

The authors conclude that, for patients with BRLP, SMT plus HEA was more effective than HEA alone after 12 weeks, but the benefit was sustained only for some secondary outcomes at 52 weeks.

This is yet another pragmatic trial following the notorious and increasingly popular A+B versus B design. As pointed out repeatedly on this blog, this study design can hardly ever generate a negative result (A+B is always more than B, unless A has a negative value [which even placebos don't have]). Thus it is not a true test of the experimental treatment but all an exercise to create a positive finding for a potentially useless treatment. Had the investigators used any mildly pleasant placebo with SMT, the result would have been the same. In this way, they could create results showing that getting a £10 cheque or meeting with pleasant company every other day, together with HEA, is more effective than HEA alone. The conclusion that the SMT, the cheque or the company have specific effects is as implicit in this article as it is potentially wrong.

The authors claim that their study was limited because patient-blinding was not possible. This is not entirely true, I think; it was limited mostly because it failed to point out that the observed outcomes could be and most likely are due to a whole range of factors which are not directly related to SMT and, most crucially, because its write-up, particularly the conclusions, wrongly implied cause and effect between SMT and the outcome. A more accurate conclusion could have been as follows: SMT plus HEA was more effective than HEA alone after 12 weeks, but the benefit was sustained only for some secondary outcomes at 52 weeks. Because the trial design did not control for non-specific effects, the observed outcomes are consistent with SMT being an impressive placebo.

No such critical thought can be found in the article; on the contrary, the authors claim in their discussion section that the current trial adds to the much-needed evidence base about SMT for subacute and chronic BRLP. Such phraseology is designed to mislead decision makers and get SMT accepted as a treatment of conditions for which it is not necessarily useful.

Research where the result is known before the study has even started (studies with a A+B versus B design) is not just useless, it is, in my view, unethical: it fails to answer a real question and is merely a waste of resources as well as an abuse of patients willingness to participate in clinical trials. But the authors of this new trial are in good and numerous company: in the realm of alternative medicine, such pseudo-research is currently being published almost on a daily basis. What is relatively new, however, that even some of the top journals are beginning to fall victim to this incessant stream of nonsense.

Chiropractors, like other alternative practitioners, use their own unique diagnostic tools for identifying the health problems of their patients. One such test is the Kemp’s test, a manual test used by most chiropractors to diagnose problems with lumbar facet joints. The chiropractor rotates the torso of the patient, while her pelvis is fixed; if manual counter-rotative resistance on one side of the pelvis by the chiropractor causes lumbar pain for the patient, it is interpreted as a sign of lumbar facet joint dysfunction which, in turn would be treated with spinal manipulation.

All diagnostic tests have to fulfil certain criteria in order to be useful. It is therefore interesting to ask whether the Kemp’s test meets these criteria. This is precisely the question addressed in a recent paper. Its objective was to evaluate the existing literature regarding the accuracy of the Kemp’s test in the diagnosis of facet joint pain compared to a reference standard.

All diagnostic accuracy studies comparing the Kemp’s test with an acceptable reference standard were located and included in the review. Subsequently, all studies were scored for quality and internal validity.

Five articles met the inclusion criteria. Only two studies had a low risk of bias, and three had a low concern regarding applicability. Pooling of data from studies using similar methods revealed that the test’s negative predictive value was the only diagnostic accuracy measure above 50% (56.8%, 59.9%).

The authors concluded that currently, the literature supporting the use of the Kemp’s test is limited and indicates that it has poor diagnostic accuracy. It is debatable whether clinicians should continue to use this test to diagnose facet joint pain.

The problem with chiropractic diagnostic methods is not confined to the Kemp’s test, but extends to most tests employed by chiropractors. Why should this matter?

If diagnostic methods are not reliable, they produce either false-positive or false-negative findings. When a false-negative diagnosis is made, the chiropractor might not treat a condition that needs attention. Much more common in chiropractic routine, I guess, are false-positive diagnoses. This means chiropractors frequently treat conditions which the patient does not have. This, in turn, is not just a waste of money and time but also, if the ensuing treatment is associated with risks, an unnecessary exposure of patients to getting harmed.

The authors of this review, chiropractors from Canada, should be praised for tackling this subject. However, their conclusion that “it is debatable whether clinicians should continue to use this test to diagnose facet joint pain” is in itself highly debatable: the use of nonsensical diagnostic tools can only result in nonsense and should therefore be disallowed.

The above title was used for a Statement for Healthcare Professionals From the American Heart Association/American Stroke Association

I have taken the liberty to quote its abstract in full:

Purpose—Cervical artery dissections (CDs) are among the most common causes of stroke in young and middle-aged adults. The aim of this scientific statement is to review the current state of evidence on the diagnosis and management of CDs and their statistical association with cervical manipulative therapy (CMT). In some forms of CMT, a high or low amplitude thrust is applied to the cervical spine by a healthcare professional.

Methods—Members of the writing group were appointed by the American Heart Association Stroke Council’s Scientific Statements Oversight Committee and the American Heart Association’s Manuscript Oversight Committee. Members were assigned topics relevant to their areas of expertise and reviewed appropriate literature, references to published clinical and epidemiology studies, morbidity and mortality reports, clinical and public health guidelines, authoritative statements, personal files, and expert opinion to summarize existing evidence and to indicate gaps in current knowledge.

Results—Patients with CD may present with unilateral headaches, posterior cervical pain, or cerebral or retinal ischemia (transient ischemic or strokes) attributable mainly to artery–artery embolism, CD cranial nerve palsies, oculosympathetic palsy, or pulsatile tinnitus. Diagnosis of CD depends on a thorough history, physical examination, and targeted ancillary investigations. Although the role of trivial trauma is debatable, mechanical forces can lead to intimal injuries of the vertebral arteries and internal carotid arteries and result in CD. Disability levels vary among CD patients with many having good outcomes, but serious neurological sequelae can occur. No evidence-based guidelines are currently available to endorse best management strategies for CDs. Antiplatelet and anticoagulant treatments are both used for prevention of local thrombus and secondary embolism. Case-control and other articles have suggested an epidemiologic association between CD, particularly vertebral artery dissection, and CMT. It is unclear whether this is due to lack of recognition of preexisting CD in these patients or due to trauma caused by CMT. Ultrasonography, computed tomographic angiography, and magnetic resonance imaging with magnetic resonance angiography are useful in the diagnosis of CD. Follow-up neuroimaging is preferentially done with noninvasive modalities, but we suggest that no single test should be seen as the gold standard.

Conclusions—CD is an important cause of ischemic stroke in young and middle-aged patients. CD is most prevalent in the upper cervical spine and can involve the internal carotid artery or vertebral artery. Although current biomechanical evidence is insufficient to establish the claim that CMT causes CD, clinical reports suggest that mechanical forces play a role in a considerable number of CDs and most population controlled studies have found an association between CMT and VAD stroke in young patients. Although the incidence of CMT-associated CD in patients who have previously received CMT is not well established, and probably low, practitioners should strongly consider the possibility of CD as a presenting symptom, and patients should be informed of the statistical association between CD and CMT prior to undergoing manipulation of the cervical spine.

In my view, this is an important statement to which I have little to add – however, I hope that the readers of this post will have comments, criticisms, observations, opinions, etc.

Some chiropractors claim that their main intervention, spinal manipulation, works for nonspecific neck pain by improving inter-vertebral range of motion (IV-RoM). But IV-RoM is difficult to measure, and whether it is related to clinical outcomes seems uncertain. Researchers from the Institute of Musculoskeletal Research & Clinical Implementation and the Anglo-European College of Chiropractic have just published a study that might throw some light on this issue. According to its authors, it was aimed at answering the following research questions:

  • Does cervical spine flexion and extension IV-RoM increase after a course of spinal manipulation?
  • Is there a relationships between any IV-RoM increases and clinical outcomes?
  • How does palpation compare with objective measurement in the detection of hypo-mobile segments?

Thirty patients with nonspecific neck pain and 30 healthy controls matched for age and gender received quantitative fluoroscopy (QF) screenings to measure flexion and extension IV-RoM (C1-C6) at baseline and 4-week follow-up. Patients received up to 12 neck manipulations and completed NRS, NDI and Euroqol 5D-5L at baseline, plus PGIC and satisfaction questionnaires at follow-up. IV-RoM accuracy, repeatability and hypo-mobility cut-offs were determined. Minimal detectable changes (MDC) over 4 weeks were calculated from controls. Patients and control IV-RoMs were compared at baseline as well as changes in patients over 4 weeks. Correlations between outcomes and the number of manipulations received and the agreement (Kappa) between palpated and QF-detected of hypo-mobile segments were calculated.

QF had high accuracy (worst RMS error 0.5σ) and repeatability (highest SEM 1.1σ, lowest ICC 0.9σ) for IV-RoM measurement. Hypo-mobility cut offs ranged from 0.8σ to 3.5σ. No outcome was significantly correlated with increased IV-RoM above MDC and there was no significant difference between the number of hypo-mobile segments in patients and controls at baseline or significant increases in IV-RoMs in patients. However, there was a modest and significant correlation between the number of manipulations received and the number of levels and directions whose IV-RoM increased beyond MDC (Rho=0.39, p=0.043). There was also no agreement between palpation and QF in identifying hypo-mobile segments (Kappa 0.04-0.06).

The authors concluded that this study found no differences in cervical sagittal IV-RoM between patients with non-specific neck pain and matched controls. There was a modest dose-response relationship between the number of manipulations given and number of levels increasing IV-RoM – providing evidence that neck manipulation has a mechanical effect at segmental levels. However, patient-reported outcomes were not related to this.

This conclusion seems a little odd to me. In my view the study suggests a clearly negative answer to all the three research questions formulated above. An interesting paragraph from the authors’ discussion section provides further insight: The lack of a relationship between symptomatic improvement and increased IV-RoM is also of interest. Clearly other mechanisms that improved the comfort and functional capacity of the patients in this study were in play, including spontaneous recovery. Other important biological factors may have included chemical factors in joint and muscle and activation patterns in the latter. However, this study seemed to rule out central pain hypersensitivity as a factor, as this was not detected at baseline in any of the patients. Psychological and social factors and their influence on functional behavior may also have had a role and may have been influenced by the interventions received.

So, spinal manipulation does not seem to work by improving IV-RoM. Could this be because spinal manipulation does not work at all?

What is the best treatment for the millions of people who suffer from chronic low back pain (CLBP)? If we are honest, no therapy has yet been proven to be overwhelmingly effective. Whenever something like that happens in medicine, we have a proliferation of interventions which all are promoted as effective but which, in fact, work just marginally. And sure enough, in the case of CLBP, we have a constantly growing list of treatments none of which is really convincing.

One of the latest additions to this list is PILATES.

Pilates? What is this ? One practitioner describes it as follows: In Pilates, we pay a lot of attention to how our body parts are lined up in relation to each other, which is our alignment. We usually think of our alignment as our posture, but good posture is a dynamic process, dependent on the body’s ability to align its parts to respond to varying demands effectively. When alignment is off, uneven stresses on the skeleton, especially the spine, are the result. Pilates exercises, done with attention to alignment, create uniform muscle use and development, allowing movement to flow through the body in a natural way.

For example, one of the most common postural imbalances that people have is the tendency to either tuck or tilt the pelvis. Both positions create weaknesses on one side of the body and overly tight areas on the other. They deny the spine the support of its natural curves and create a domino effect of aches and pains all the way up the spine and into the neck. Doing Pilates increases the awareness of the proper placement of the spine and pelvis, and creates the inner strength to support the natural curves of the spine. This is called having a neutral spine and it has been the key to better backs for many people.

Mumbo-jumbo? Perhaps; in any case, we need evidence! Is there any at all? Surprisingly, the answer is yes. Recently, someone even published a proper systematic review.

This systematic review was aimed at evaluating the effectiveness of Pilates exercise in people with chronic low back pain (CLBP).

A search for RCTs was undertaken in 10 electronic. Two independent reviewers did the selection of evidence and evaluated the quality of the primary studies. To be included, relevant RCTs needed to be published in the English language. From 152 studies, 14 RCTs could be included.

The methodological quality of RCTs ranged from “poor” to “excellent”. A meta-analysis of RCTs was not undertaken due to the heterogeneity of RCTs. Pilates exercise provided statistically significant improvements in pain and functional ability compared to usual care and physical activity between 4 and 15 weeks, but not at 24 weeks. There were no consistent statistically significant differences in improvements in pain and functional ability with Pilates exercise, massage therapy, or other forms of exercise at any time period.

The authors drew the following conclusions: Pilates exercise offers greater improvements in pain and functional ability compared to usual care and physical activity in the short term. Pilates exercise offers equivalent improvements to massage therapy and other forms of exercise. Future research should explore optimal Pilates exercise designs, and whether some people with CLBP may benefit from Pilates exercise more than others.

So, Pilates can be added to the long list of treatments that work for CLBP, albeit not convincingly better than most other therapies on offer. Does that mean these options are all as good or as bad as the next? I don’t think so.

Let’s assume chiropractic/osteopathic manipulations, massage and various forms of exercise are all equally effective. How do we decide which is more commendable than the next? We clearly need to take other important factors into account:

  • cost
  • risks
  • acceptability for patients
  • availability

If we use these criteria, it becomes instantly clear that chiropractic and osteopathy are not favourites in this race for the most commendable CLBP-treatment. They are neither cheap nor free of risks. Massage is virtually risk-free but not cheap. This leaves us with various forms of exercise, including Pilates. But which exercise is better than the next? At present, we do not know, and therefore the last two factors are crucial: if people love doing Pilates and if they easily stick with it, then Pilates is fine.

I am sure chiropractors will (yet again) disagree with me but, to me, this logic could hardly be more straight forward.

Many proponents of chiropractic claim that chiropractic spinal manipulation therapy (SMT) for chronic low back pain (LBP) might save health care cost. As LBP is a hugely expensive condition, this is a mighty important question. The evidence on this issue is, however, flimsy to say the least. Most experts seem to conclude that more reliable data are needed. On this background, it seems relevant to note that a new relevant study has just become available.

The purpose of this analysis was to report the incremental costs and benefits of different doses of SMT in patients with LBP.

The researchers randomized 400 patients with chronic LBP to receive doses of 0, 6, 12, or 18 sessions of SMT. Patients were scheduled for 18 visits for 6 weeks and received SMT or light massage control from a chiropractor. Societal costs in the year after study enrollment were estimated using patient reports of health care use and lost productivity. The main health outcomes were the number of pain-free days and disability-free days.

The results show that costs for treatment and lost productivity ranged from $3398 for 12 SMT sessions to $3815 for 0 SMT sessions with no statistically significant differences between groups. Baseline patient characteristics related to increase in costs were greater age, greater disability, lower quality-adjusted life year scores, and higher costs in the period preceding enrolment. Pain-free and disability-free days were greater for all SMT doses compared with control, but only SMT 12 yielded a statistically significant benefit of 22.9 pain-free days and 19.8 disability-free days. No statistically significant group differences in quality-adjusted life years were noted.

The authors drew the following conclusions from these data: a dose of 12 SMT sessions yielded a modest benefit in pain-free and disability-free days. Care of chronic LBP with SMT did not increase the costs of treatment plus lost productivity.

So, is chiropractic SMT for LBP cost-effective? I leave it to my readers to answer this question.

The question whether infant colic can be effectively treated with manipulative therapies might seem rather trivial – after all, this is a benign condition which the infant quickly grows out of. However, the issue becomes a little more tricky, if we consider that it was one of the 6 paediatric illnesses which were at the centre of the famous libel case of the BCA against my friend and co-author Simon Singh. At the time, Simon had claimed that there was ‘not a jot of evidence’ for claiming that chiropractic was an effective treatment of infant colic, and my systematic review of the evidence strongly supported his statement. The BCA eventually lost their libel case and with it the reputation of chiropractic. Now a new article on this intriguing topic has become available; do we have to reverse our judgements?

The aim of this new systematic review was to evaluate the efficacy or effectiveness of manipulative therapies for infantile colic. Six RCTs of chiropractic, osteopathy or cranial osteopathy alone or in conjunction with other interventions were included with a total of 325 infants. Of the 6 included studies, 5 were “suggestive of a beneficial effect” and one found no evidence of benefit. Combining all the RCTs suggested that manipulative therapies had a significant effect. The average crying time was reduced by an average of 72 minutes per day. This effect was sustained for studies with a low risk of selection bias and attrition bias. When analysing only those studies with a low risk of performance bias (i.e. parental blinding) the improvement in daily crying hours was no longer statistically significant.

The quality of the studies was variable. There was a generally low risk of selection bias but a high risk of performance bias. Only one of the studies recorded adverse events and none were encountered.

From these data, the authors drew the following conclusion: Parents of infants receiving manipulative therapies reported fewer hours crying per day than parents whose infants did not and this difference was statistically significant. 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.

Does that mean that chiropractic does work for infant colic? No, it does not!

The first thing to point out is that the new systematic review included not just RCTs of chiropractic but also osteopathy and cranio-sacral therapy.

The second important issue is that the effects disappear, once performance bias is being accounted for which clearly shows that the result is false positive.

The third relevant fact is that the majority of the RCTs were of poor quality. The methodologically best studies were negative.

And the fourth thing to note is that only one study mentioned adverse effects, which means that the other 5 trials were in breach of one of rather elementary research ethics.

What makes all of this even more fascinating is the fact that the senior author of the new publication, George Lewith, is the very expert who advised the BCA in their libel case against Simon Singh. He seems so fond of his work that he even decided to re-publish it using even more misleading language than before. It is, of course, far from me to suggest that his review was an attempt to white-wash the issue of chiropractic ‘bogus’ claims. However, based on the available evidence, I would have formulated conclusions which are more than just a little different from his; something like this perhaps:

The current best evidence suggests that the small effects that emerge when we pool the data from mostly unreliable studies are due to bias and therefore not real. This systematic review therefore fails to show that manipulative therapies are effective. It furthermore points to a serious breach of research ethics by the majority of researchers in this field.

The mechanisms thorough which spinal manipulative therapy (SMT) exerts its alleged clinical effects are not well established. A new study investigated the effects of subject expectation on clinical outcomes.

Sixty healthy subjects underwent quantitative sensory testing to their legs and low backs. They were randomly assigned to receive a positive, negative, or neutral expectation instructional set regarding the effects of a spe cific SMT technique on pain perception. Following the instructional set, all subjects received SMT and underwent repeat sensory tests.

No inter-group differences in pain response were present in the lower extremity following SMT. However, a main effect for hypoalgesia was present. A significant interaction was present between change in pain perception and group assignment in the low back with participants receiving a negative expectation instructional set demonstrating significant hyperalgesia.

The authors concluded that this study provides preliminary evidence for the influence of a non- specific effect (expectation) on the hypoalgesia associated with a single session of SMT in normal subjects. We replicated our previous findings of hypoalgesia in the lower extremity associated with SMT to the low back. Additionally, the resultant hypoalgesia in the lower extremity was independent of an expectation instructional set directed at the low back. Conversely, participants receiving a negative expectation instructional set demonstrated hyperalgesia in the low back following SMT which was not observed in those receiving a positive or neutral instructional set.

More than 10 years ago, we addressed a similar issue by conducting a systematic review of all sham-controlled trials of SMT. Specifically, we wanted to summarize the evidence from sham-controlled clinical trials of SMT. Eight studies fulfilled our inclusion/exclusion criteria. Three trials (two on back pain and one on enuresis) were judged to be burdened with serious methodological flaws. The results of the three most rigorous studies (two on asthma and one on primary dysmenorrhea) did not suggest that SMT leads to therapeutic responses which differ from an inactive sham-treatment. We concluded that sham-controlled trials of SMT are sparse but feasible. The most rigorous of these studies suggest that SMT is not associated with clinically relevant specific therapeutic effects.

Taken together, these two articles provide intriguing evidence to suggest that SMT is little more than a theatrical placebo. Given the facts that SMT is neither cheap nor devoid of risks, the onus is now on those who promote SMT, e.g. chiropractors, osteopaths and physiotherapists, to show that this is not true.

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