EPISTEMOLOGY

Faith as a basis for practice

Historically the benefits of joint manipulation have been disputed, so we might reasonably ask whether at different times those who made use of manipulation were justified in asserting that their methods had therapeutic value. Epistemology is the branch of philosophy which deals with claims to knowledge. From ancient to modern times it has been an indispensable part of philosophy. Scholars have long argued about claims to knowledge, about what constitutes knowledge and what does not. Some have contended that we can know things through inspiration, for example through divine revelation. Some have emphasized the value of personal experience. Others have highlighted the contribution of rational thinking. Yet others have argued that in order to better understand what is true and what is not we should systematically examine the natural world. There has been interplay between these different approaches.

As natural philosophy became science, especially in the nineteenth century, the foundations of established medical knowledge became more naturalistic. Supernaturalism was de-emphasized as scientific evidence was used to provide justification for belief. Systematic study of testable hypotheses added strength to claims to knowledge. Where they were found wanting, hypotheses were rejected or modified. Where verified, they provided a basis for practice. By the end of the twentieth century evidence-based medicine, involving the conscientious, explicit and judicious use of scientific research had become the vogue (Sackett et al., 1996).

Fundamental to the understanding of claims to knowledge in medicine generally, and in manipulative practice specifically, is the distinction between testable and untestable hypotheses. Over the centuries there have been practitioners of joint manipulation who have claimed that their ideas were developed through divine or spiritual inspiration. Their claims could not and cannot be tested. They were and remain unverifiable and unfalsifiable, subject to faith. When in the sixth century Bishop Gregory of Tours was critical of the practices of Desiderius, he believed his authority to come from God. When Andrew Still reflected on the loss of three members of his family to meningitis, his belief in a loving God shaped his response and the subsequent development of osteopathy. When Daniel Palmer founded chiropractic asserting that Jim Atkinson guided him, spiritualism influenced his claim to knowledge. Faith provided direction for these people, but faith in an idea does not in itself make the idea true. The existence of conflicting religious and spiritual beliefs shows this to be the case. Consequentially, the notion that faith was or is a satisfactory foundation for the practice of joint manipulation is called into question.

Experience as a basis for practice

If after a fall a dislocated shoulder is not returned to its normal position experience has shown that it will not heal properly and function will be lost, therefore use of manipulation is justified. This, we might argue, is sensible even if we understand that there are risks involved in the procedure, including the possibility of compromise to nerves and blood vessels. Historically, many practitioners of manual therapy grounded their belief in manipulation on personal experience and on the cumulative experiences of others, maintaining that experience justified their belief. In effect the argument was that the proof of the pudding was in the eating. We know that manipulation works because we have seen it work and because others have seen it work. This was the attitude of the bone-setter Herbert Barker who encouraged medical doctors to come and observe him. It was also the attitude of many early chiropractors, who as Steven Martin (1994) noted, based their belief in the effectiveness of manipulation on observing the treatment of large numbers of patients.

When a patient attends with a stiff and painful neck, is adjusted, and immediately experiences improved movement and reduced pain, it is not unreasonable to assume that the adjustment caused the change, but when the change is more gradual then there is more reason to doubt cause and effect. Experiences can be misinterpreted. When a person’s livelihood depends upon the use of manual therapy, and when that person is part of a culture that supports its use, having a positive disposition towards manipulation is to be expected. When a patient gets better following a course of manipulative treatment, both clinician and patient might assume that the treatment provided was responsible, but the fact that manipulation was used does not establish beyond doubt that manipulation was responsible for the improvement. Other factors might have influenced the outcome, including natural history and the placebo effect.

In the field of manipulative practice inspiration and experience gave rise to tradition and the institutionalization of belief. Charismatic leaders promoted the use of manipulation and were persuasive in their advocacy. The chiropractor Bartlett Palmer was one example. Sid Williams described how he was profoundly affected by him (Williams, 1990):

“When he began to speak there was no warm up or pussyfooting around: it was as if he were Moses himself. His voice had a sharp, crisp Midwestern tone and he was very authoritative. And he spoke as if he were THE ONE in authority, as if he had been given the torch and the message straight from the source …

When the full impact of B.J’s “Big Idea” hit me, I was more excited and more uplifted than I have ever been before. I felt I had full authority. I knew I was right. It was as if I’d entered a new age. I could see the light.”

Regrettably charismatic authority is no determinant of truth. Neither are eloquence or charm. When an idea is presented with flair it can be enticing, whether or not it is true. The key to improved understanding lies in critical thinking.

Science as a basis for practice

From the foregoing discussion we can conclude that there are limitations in using inspiration and experience as foundations for claims to knowledge, whether in manual therapy or in other fields. We cannot conclude that they are without value, but they are fallible. One response to their limitations has been science, which has involved testing the testable. With regard to manipulation, a scientific position might be formulated as follows: If we wish to discover whether joint manipulation is of therapeutic value, we should not simply rely on hearsay, personal experience and/or inspiration, but undertake systematic and rigorous assessment of outcomes as they happen in the natural world.

The application of rigorous scientific study to the practice of joint manipulation has been a relatively recent phenomenon. When in 1975 a workshop was convened by the National Institutes of Health in the United States to examine the research status of spinal manipulative therapy, no data from controlled clinical trials was presented to support or refute the efficacy of manipulation for low back pain (Goldstein, 1975, p. 6). Since 1975 an increasing number of articles have appeared in peer-reviewed journals that have provided substantive evidence for and against the use of joint manipulation for different conditions. That evidence has been subject to systematic review and has formed a part of practice guidelines. So, for example, in 2016, in Britain, the National Institute for Health and Care Excellence published guidance on the use of manual therapy for low back pain and sciatica. Their guidance recommended that manual therapy be considered for use in the management of low back pain with or without sciatica, but notably only as part of a treatment package including exercise, with or without psychological therapy. In other words, only as part of a multimodal strategy.

The scientific evidence favouring the use of joint manipulation for common musculoskeletal conditions, such as back pain, is modest (Bronfort et al., 2010; Clar et al. 2014). The scientific evidence favouring its use for non-musculoskeletal conditions is more limited and controversial (Côté et al., 2021). Studies suggest that serious adverse effects of manipulation are rare, but do exist (Barrett and Breen, 2000; Ernst, 2007).

Science has increased our understanding of the benefits and risks of manipulation, but it is important to understand that science, like other claims to knowledge, is imperfect. An outcomes study undertaken at a particular time and place will only be meaningful to clinical decision making if its findings can usefully be applied subsequently and in other places. Reproducibility is a cornerstone of good science, but even where confirmatory studies exist, drawing general conclusions from particular observations remains problematic. As the philosopher Karl Popper pointed out (Popper, 1959, p. 27):

“it is far from obvious, from a logical point of view, that we are justified in inferring universal statements from singular ones, no matter how numerous; for any conclusion drawn in this way may always turn out to be false: no matter how many instances of white swans we may have observed, this does not justify the conclusion that all swans are white.”

In recent decades randomized controlled clinical trials have been considered by many to offer a gold standard in clinical outcomes research. In a randomized controlled trial selected patients are randomly assigned into two or more groups. One group is provided with the intervention under investigation, while the others receive an alternative or placebo intervention. Outcomes are then compared. Blinding has sometimes been used in order to reduce risk of bias. Where blinding is employed, subjects do not know which study group they are in. Sometimes blinding has been extended to include the researchers and those involved in statistical analysis. Unfortunately, blinding has presented practical challenges for those studying manipulation. In explanatory or fastidious trials contextual factors are controlled in an attempt to provide an optimal environment for assessment, but with exclusion criteria and highly controlled settings comes the risk that studies do not accurately reflect the complexities of real life. There are those who think that a more pragmatic approach to outcomes research, an approach that reflects routine practice conditions, has advantages. Moreover, aside from the fact that science can be influenced by other agendas, there are some who believe that the proof of the pudding really is in the eating, not in scientific examination of its constituent parts, nor in blinded comparison with a faux pudding.

Placebo

In 1990 the British Medical Journal reported the findings of a pragmatic randomized comparison of chiropractic and hospital outpatient management for ‘mechanical’ low back pain (Meade et al., 1990). The study compared the effectiveness of these approaches as they were utilized in everyday practice, rather than employing a more fastidious design. The results suggested chiropractic to be slightly more effective, but there were those who believed this conclusion to be flawed. Among those who criticized the study was Michael Edgar, an orthopaedic surgeon. He questioned whether it was wise (Edgar, 1990):

“to compare the results of private and unhurried sessions of chiropractic treatment with those from the average overworked and usually understaffed service of an NHS hospital physiotherapy department.”

In doing so he drew attention to the effects of contextual factors on clinical outcomes. Might it have been the environment in which chiropractic was practised, rather than the chiropractic treatment itself, that formed the basis for its positive comparison with hospital outpatient management? In outcomes research there is a tendency to consider an intervention without merit if its benefit is no more than placebo, but in clinical practice any factor that can be used to improve outcomes is worthy of consideration. There is growing evidence that therapeutic context can play a role in symptom relief, producing meaningful changes within the brain and body (Ongaro and Kaptchuk, 2019). Placebo is the clinician’s friend. A positive and caring manner, a conducive environment, time, touch and the ‘crack’ of an adjustment – all of these might influence outcome.

The word placebo has its roots in classical Latin and has been translated into English as “I shall be pleasing or acceptable” (Oxford English Dictionary, 2022). In medicine, it is the patient that the doctor is endeavouring to please. In defining evidence-based medicine, David Sackett and his colleagues emphasized that good practice entailed not only the best use of research evidence, but also the ability to integrate clinical skills and the clinician’s past experiences with the patient’s own values and unique preferences (Sackett et al., 2000, p. 1). Scientific evidence was not enough. Scientism, extreme or excessive reliance on science, was to be avoided. The patient’s wishes were to be taken into account.

References

Barrett A.J. and Breen A.C. (2000). Adverse effects of spinal manipulation. Journal of the Royal Society of Medicine 93, 258-259.

Bronfort G., Haas M., Evans R., Leininger B. and Triano J. (2010). Effectiveness of manual therapies: the UK evidence report. Chiropractic and Osteopathy 18 (3).

Clar C., Tsertsvadze A., Court R., Hundt G.L., Clarke A. and Sutcliffe P. (2014). Clinical effectiveness of manual therapy for the management of musculoskeletal and non-musculoskeletal conditions: systematic review and update of UK evidence report. Chiropractic and Manual Therapies 22 (12).

Côté P. et al. (2021). The global summit on the efficacy and effectiveness of spinal manipulative therapy for the prevention and treatment of non-musculoskeletal disorders: a systematic review of the literature. Chiropractic and Manual Therapies 29 (8).

Edgar M.A. (1990). Correspondence. Low back pain: comparison of chiropractic and hospital outpatient treatment. British Medical Journal 300 (6740), 1648.

Ernst E. (2007). Adverse effects of spinal manipulation: a systematic review. Journal of the Royal Society of Medicine 100, 330-338.

Goldstein M. [editor] (1975). The Research Status of Spinal Manipulative Therapy. A workshop held at the National Institutes of Health. U.S. Department of Health, Education and Welfare, Washington.

Martin S.C. (1994). The only truly scientific method of healing. Chiropractic and American science, 1895-1990. Isis 85 (2), 207-227.

Meade T.W., Dyer S., Browne W., Townsend J. and Frank A.O. (1990). Low back pain of mechanical origin: randomised comparison of chiropractic and hospital outpatient treatment. British Medical Journal 300 (6737), 1431-1437.

National Institute for Health and Care Excellence (2016). Low Back Pain and Sciatica in Over 16s: Assessment and Management. NICE Guideline [NG59]. London.

Ongaro G. and Kaptchuk T.J. (2019). Symptom perception, placebo effects, and the Bayesian brain. Pain 160 (1), 1-4.

Oxford English Dictionary (2022). Placebo. Oxford English Dictionary (Third edition). Modified online version. March 2022. Oxford University Press, Oxford.

Popper K.R. (1959). The Logic of Scientific Discovery. English translation of Logik der Forschung, originally published in German in 1934. Hutchinson & Co., London.

Sackett, D.L., Rosenberg W.M.C., Gray J.A.M., Haynes R.B. and Richardson W.S. (1996). Evidence based medicine; what it is and what it isn’t. British Medical Journal 312 (7023), 71-72.

Sackett D.L., Straus S.E., Richardson W.S., Rosenburg W and Haynes R.B. (2000). Evidence-Based Medicine. How to Practice and Teach EBM. Churchill Livingstone, Edinburgh.

Williams S.E. (1990). Crossing the river. Today’s Chiropractic. November/December issue, pp. 7-8 and 76-77.

NEXT PAGE