Adeverse events and reactions after chiropractic treatment may not be the result of the treatment itself, a Murdoch University study has found.
The study, published in Spine, used 'sham' or placebo therapy and other methods to assess the effects of chiropractic treatment on patients.
Co-author and Murdoch University School of Psychology and Exercise Science, Rehabilitation Science's Jeffery Hebert says chiropractic treatments such as spinal manipulative therapy are hands on manual therapy.
"It is common for patients to report soreness following treatment similar to that experienced when starting a new type of exercise," Mr Hebert says.
"What we did not know was how often these problems resulted from the actual treatment versus the natural fluctuations that frequently occur among people with neck and back pain.
"In this study, we were mainly interested in the reporting of adverse events or problems following treatment.
"We expected that the frequency and intensity of these problems would be quite different between the groups."
What Mr Hebert and the team found was that there were no differences in the reporting of adverse events between people receiving the chiropractic treatment and those experiencing the simulated treatment.
"We think this means that, in many cases, increased pain or the occurrence of other symptoms that may follow chiropractic treatment, are not caused by the treatment itself," he says.
The study was the first to use a sham-controlled randomised trial to investigate the occurrence of adverse events following soft manipulative therapy (SMT).
Mr Hebert says developing a sham therapy for hands-on treatment such as SMT was difficult to simulate, but was only one of the methods used by chiropractors during the trial.
The study included people with spinal pain, and provided them with one of two types of therapy involving either treatments with a chiropractor or a simulated treatment that was expected to have no therapeutic effect.
Among the 180 people in the study, there were no serious adverse events reported. Of those receiving chiropractic treatment, 42 per cent of people reported experiencing a more minor adverse event, which most commonly involved increased pain, muscle stiffness and headache.
Mr Hebert says this compares to 33 per cent of people receiving the simulated therapy.
"The numbers appeared to indicate that people receiving the chiropractic treatment were more likely to report more intense adverse events; however, this difference was not statistically significant," he says.
"A larger study will need to be conducted to understand these issues better."
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"Outcomes of usual chiropractic. The OUCH randomized controlled trial of adverse events." Walker BF, Hebert JJ, Stomski NJ, Clarke BR, Bowden RS, Losco B, French SD. Spine (Phila Pa 1976). 2013 Sep 15;38(20):1723-9. DOI: 10.1097/BRS.0b013e31829fefe4.