PainSci summary of Paige 2017: ?This page is one of thousands in the PainScience.com 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.
The idea of “adjusting” the spine refers to many different manual therapies that wiggle, pop, and otherwise manipulate spinal joints. This is “spinal manipulative therapy” or SMT, one of the most famous of all hands-on therapies and the defining feature of chiropractic therapy (although it is offered by some other healthcare professionals, mainly physical therapists and osteopaths).
Although expert opinions on SMT range widely, the use of SMT for acute back pain specifically has long been regarded even by many critics as the closest thing to an evidence-based treatment in alternative health care, chiropractic’s crown jewel. Therefore, it ought to really shine when tested.
This major new review of SMT, published in Journal of the American Medical Association, pools the results of 26 studies of SMT for fresh cases of back pain (less than six weeks). Fifteen of those studies provided “moderate-quality evidence” of “clinically modest” effects on pain, roughly a 1-point improvement on a 10-scale on average in the short term, “the same as the benefit for nonsteroidal anti-inflammatory drugs in acute low back pain.” (The remaining studies reviewed did not provide any supporting evidence, for various reasons.)
That’s not much of a shine, so it’s strange that this review has been loudly touted by some as good news. Claiming it as a victory is one of the best examples I’ve ever seen of making lemonade out of science lemons! But I can understand the mistake, because the review itself seems positive at first glance: the benefits of SMT are summarized as “statistically significant” in the abstract, which sounds like good news if you don’t keep reading. The same results are also described as “clinically modest,” and even that seems excessively generous to me: personally, I need at least a 2-point drop to consider it a “modest” improvement!
This is not a clearly positive review: it shows weak evidence of minor efficacy, based on “significant unexplained heterogeneity” in the results. That is, the results were all over the place (but without impressive benefits reported by any study), and the mixture can’t be explained by any obvious, measurable factor. This probably means there’s just a lot of noise in the data, too many things that are at least as influential as the treatment itself. Or — more optimistically — it could mean that SMT is “just” disappointingly mediocre on average, but might have more potent benefits in a minority of cases (that no one seems to be able to reliably identify).
Far from being good news, this review continues a strong trend (eg Rubinstein 2012) of damning SMT with faint praise, but it also adds evidence of backfiring to mix. Although “no RCT reported any serious adverse event,” fortunately, it seems that minor harms were legion: “increased pain, muscle stiffness, and headache were reported 50% to 67% of the time in large case series of patients treated with SMT.” That’s a lot of undesirable outcomes.
So the average patient has a roughly fifty-fifty chance of up to roughly a 20% improvement … or actually feeling worse to some unknown degree! That does not sound like a good deal to me.
original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
Importance: Acute low back pain is common and spinal manipulative therapy (SMT) is a treatment option. Randomized clinical trials (RCTs) and meta-analyses have reported different conclusions about the effectiveness of SMT.
Objective: To systematically review studies of the effectiveness and harms of SMT for acute (≤6 weeks) low back pain.
Data Sources: Search of MEDLINE, Cochrane Database of Systematic Reviews, EMBASE, and Current Nursing and Allied Health Literature from January 1, 2011, through February 6, 2017, as well as identified systematic reviews and RCTs, for RCTs of adults with low back pain treated in ambulatory settings with SMT compared with sham or alternative treatments, and that measured pain or function outcomes for up to 6 weeks. Observational studies were included to assess harms.
Data Extraction and Synthesis: Data extraction was done in duplicate. Study quality was assessed using the Cochrane Back and Neck (CBN) Risk of Bias tool. This tool has 11 items in the following domains: randomization, concealment, baseline differences, blinding (patient), blinding (care provider [care provider is a specific quality metric used by the CBN Risk of Bias tool]), blinding (outcome), co-interventions, compliance, dropouts, timing, and intention to treat. Prior research has shown the CBN Risk of Bias tool identifies studies at an increased risk of bias using a threshold of 5 or 6 as a summary score. The evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria.
Main Outcomes and Measures: Pain (measured by either the 100-mm visual analog scale, 11-point numeric rating scale, or other numeric pain scale), function (measured by the 24-point Roland Morris Disability Questionnaire or Oswestry Disability Index [range, 0-100]), or any harms measured within 6 weeks.
Findings: Of 26 eligible RCTs identified, 15 RCTs (1711 patients) provided moderate-quality evidence that SMT has a statistically significant association with improvements in pain (pooled mean improvement in the 100-mm visual analog pain scale, -9.95 [95% CI, -15.6 to -4.3]). Twelve RCTs (1381 patients) produced moderate-quality evidence that SMT has a statistically significant association with improvements in function (pooled mean effect size, -0.39 [95% CI, -0.71 to -0.07]). Heterogeneity was not explained by type of clinician performing SMT, type of manipulation, study quality, or whether SMT was given alone or as part of a package of therapies. No RCT reported any serious adverse event. Minor transient adverse events such as increased pain, muscle stiffness, and headache were reported 50% to 67% of the time in large case series of patients treated with SMT.
- “Spinal manipulative therapy for acute low-back pain,” Sidney M Rubinstein, Caroline B Terwee, Willem J J Assendelft, Michiel R de Boer, and Maurits W van Tulder, Cochrane Database of Systematic Reviews, 2012.
- “Spinal manipulations for cervicogenic headaches: a systematic review of randomized clinical trials,” Paul Posadzki and Edzard Ernst, Headache, 2011.
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:
- Relationships Between Sleep Quality and Pain-Related Factors for People with Chronic Low Back Pain: Tests of Reciprocal and Time of Day Effects. Gerhart 2017 Ann Behav Med.
- Modulation in the elastic properties of gastrocnemius muscle heads in individuals with plantar fasciitis and its relationship with pain. Zhou 2020 Sci Rep.
- Association Between Plantar Fasciitis and Isolated Gastrocnemius Tightness. Nakale 2018 Foot Ankle Int.
- No Added Benefit of Combining Dry Needling With Guideline-Based Physical Therapy When Managing Chronic Neck Pain: A Randomized Controlled Trial. Stieven 2020 J Orthop Sports Phys Ther.
- Effectiveness of customised foot orthoses for Achilles tendinopathy: a randomised controlled trial. Munteanu 2015 Br J Sports Med.