It has long been argued that chiropractic spinal manipulations are mere placebo interventions. Yet few controlled trials have assessed the efficacy of spinal manipulative therapy (SMT). No high quality trials have been performed to test the efficacy and effectiveness of Graston Technique® (GT), an instrument-assisted soft tissue therapy.
The objective of this trial was to determine the efficacy of SMT and GT compared to sham therapy for the treatment of non-specific thoracic spine pain.
People with non-specific thoracic pain were randomly allocated to one of three groups: SMT, GT, or a placebo (de-tuned ultrasound). GT is a popular soft-tissue technique in the United States and becoming more popular in other developed countries. GT is an instrument-assisted soft-tissue therapy involving the use of hand-held stainless steel instruments. The promoters of the GT claim that the instruments resonate in the clinician’s hands allowing the clinician to isolate soft-tissue “adhesions and restrictions”, and treat them precisely. Each participant received up to 10 supervised treatment sessions at Murdoch University chiropractic student clinic over a 4 week period.
The two outcome measures were self-administered instruments. Participants were given blank questionnaires in a package by a research assistant following their first treatment. Participants were instructed to complete the instruments at each assessment time point. After completion of the forms the participant posted them back to the Murdoch University Chiropractic Clinic. Research assistants remained blind to the outcome data for the entire study period. The participants and treatment providers were not blinded to the treatment allocation as it was clear that the groups were receiving different treatments. Participants in the placebo group were blinded to their placebo allocation until follow-up was complete at 12 months. Participants were surveyed for the adequacy of the placebo blinding at the end of the study.
Treatment outcomes were measured at baseline, 1 week, and at one, three, six and 12 months. Primary outcome measures included a modified Oswestry Disability Index, and the Visual Analogue Scale (VAS). Treatment effects were estimated with intention to treat analysis and linear mixed models.
One hundred and forty three participants were randomly allocated to the three groups (SMT = 36, GT = 63 and Placebo = 44). Baseline data for the three groups did not show any meaningful differences. Results of the intention to treat analyses revealed no time by group interactions, indicating no statistically significant between-group differences in pain or disability at 1 week, 1 month, 3 months, 6 months, or 12 months. There were significant main effects of time (p < 0.01) indicating improvements in pain and disability from baseline among all participants regardless of intervention. No significant adverse events were reported.
The authors concluded that this study indicates that there is no difference in outcome at any time point for pain or disability when comparing SMT, Graston Technique® or sham therapy for thoracic spine pain, however all groups improved with time. These results constitute the first from a fully powered randomised controlled trial comparing SMT, Graston technique® and a placebo.
Some people claim that there is little wrong with placebo therapy, as long as it helps patients. This is not what I think, but even the proponents of this argument would agree that the placebo used in this way has to be safe. As SMT is by no means free of adverse effects, the argument cannot be applied here.
Other people will argue that this is about SMT and not chiropractic implying that I am conducting a vendetta against the poor chiropractors. I would disagree: we have just learnt that 93% of chiropractors consider SMT as their primary treatment. Yes, osteopaths and physiotherapists also use SMT but certainly not to this extent. Thus this discussion is mostly about chiropractic, and the onus is on chiropractors to demonstrate beyond doubt that SMT does more good than harm.
The true significance of this study is, I think, that the chiropractic profession now must convince us that spinal manipulation has any usefulness at all. They will have to conduct rigorous trials along the lines of this study to test for which condition these interventions generate outcomes that are significantly better than those achievable by sham.
Until such data are available, it would be wise, I think, to consider all therapeutic claims made for chiropractic unproven and bogus.
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