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bibliography * The PainScience Bibliography contains plain language summaries of thousands of scientific papers and others sources, like a specialized blog. This page is about a single scientific paper in the bibliography, Carnes 2010.

More than 20% of manual therapy treatments do some harm

Carnes D, Mars TS, Mullinger B, Froud R, Underwood M. Adverse events and manual therapy: a systematic review. Man Ther. 2010 Aug;15(4):355–63. PubMed #20097115.
Tags: harms, massage, chiropractic, controversy, muscle pain, back pain, neck, pain problems, manual therapy, treatment, debunkery, spine, muscle, head/neck

PainSci summary of Carnes 2010?This page is one of thousands in the bibliography. It is not a general article: it is focused on a single scientific paper, and it may provide only just enough context for the summary to make sense. Links to other papers and more general information are provided at the bottom of the page, as often as possible. ★★★★★?5-star ratings are for sentinel studies, excellent experiments with meaningful results. Ratings are a highly subjective opinion, and subject to revision at any time. If you think this paper has been incorrectly rated, please let me know.

The sound bite in this study is that 20-40% of all manual therapy treatments — massage, chiropractic, physiotherapy — will cause some kind of unpleasantness, side effect or “adverse event” in medicalspeak.

In a word: yikes!

Perspective cuts both ways here. On the one hand, it’s not as bad as it sounds: these “events” are minor and moderate in severity; only 1 or 2 per thousand visits causes a serious problem; and drugs are actually relatively worse. That is, you are modestly more likely to have an “adverse event” if you are given a pill. This just refers to typical side effects, such as ibuprofen’s tendency to cause indigestion.

But when you take a pill, the side effect is usually unrelated to the problem (i.e. it doesn’t make the problem you’re treating worse), you are generally trading those side effects for some pretty clear benefits, and it’s usually cheap. In manual therapy, most adverse events are backfires — that is, you go for a neck adjustment at the chiropractor, and you come out with more neck pain instead of less. Other data shows this is 25% more likely than if you did nothing at all (see Carlesso). And you pay through the nose for this! Manual therapy is much more expensive than most drug therapy.

Manual therapists routinely claim that their services are much safer and more effective than drug therapies. Yet this data pretty clearly shows that the difference is really not great. Depending on how you look at it, drugs are only a little worse in some ways, or maybe a little better in other ways. But no matter how you slice it, 20-40% is a pretty unpleasant rate of harm — especially at $60–120/hour!

~ Paul Ingraham

original abstract

OBJECTIVE: To explore the incidence and risk of adverse events with manual therapies.

METHOD: The main health electronic databases, plus those specific to allied medicine and manual therapy, were searched. Our inclusion criteria were: manual therapies only; administered by regulated therapists; a clearly described intervention; adverse events reported. We performed a meta-analysis using incident estimates of proportions and random effects models.

RESULTS: Eight prospective cohort studies and 31 manual therapy RCTs were accepted. The incidence estimate of proportions for minor or moderate transient adverse events after manual therapy was approximately 41% (CI 95% 17-68) in the cohort studies and 22% (CI 95% 11.1-36.2%) in the RCTs; for major adverse events approximately 0.13%. The pooled relative risk (RR) for experiencing adverse events with exercise, or with sham/passive/control interventions compared to manual therapy was similar, but for drug therapies greater (RR 0.05, CI 95% 0.01-0.20) and less with usual care (RR 1.91, CI 95% 1.39-2.64).

CONCLUSIONS: The risk of major adverse events with manual therapy is low, but around half of manual therapy patients may experience minor to moderate adverse events after treatment. The relative risk of adverse events appears greater with drug therapy but less with usual care.

related content

These five articles on cite Carnes 2010 as a source:

This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights: