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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, Steffens 2015.

What triggers an episode of acute low back pain? A case-crossover study

Steffens D, Ferreira ML, Latimer J, Ferreira PH, Koes BW, Blyth F, Li Q, Maher CG. What triggers an episode of acute low back pain? A case-crossover study. Arthritis Care Res (Hoboken). 2015 Mar;67(3):403–10. PubMed #25665074.
Tags: etiology, back pain, pro, pain problems, spine

PainSci summary of Steffens 2015?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. ★★★★☆?4-star ratings are for bigger/better studies and reviews published in more prestigious journals, with only quibbles. 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.

A fascinating experiment producing valuable data on potential triggers for episodes of acute low back pain. Basically the researchers just a did a very thorough, formal version of asking a lot of people — a thousand of them — what they were doing right before their back pain started, as compared to other recent periods. They made an admirable effort to doing this in a way that eliminated “recall bias,” but the one major concern I have about the study is that people have very strong preconceived biases about what constitutes a risk factor for back pain, and people tend to perceive and remember what they want or expect to be true. Participants were “asked to report exposure, including its time and duration, to each of the 12 putative triggers in the 96 hours preceding the onset of back pain. For example, for questions about manual tasks involving a heavy load would be as follows: so on the day of your back pain did you engage in any manual tasks involving a heavy load?” A lot of people are likely to remember it that way, because that’s what they already think causes back pain. The list of possibilities was also limited to classic putative risk factors, which means that if a risk factor isn’t a bit of a cliché, this study simply ignored it.

I think that has real potential to confound the results here.

Nevertheless, there were strong signals and fascinating patterns here, and “the results of this study demonstrate for the first time that brief exposure to a range of physical and psychosocial factors can considerably increase the risk of an episode of acute back pain.” Being distracted was by far the biggest risk: patients were twenty-five times more likely to be distracted “during an activity or task” right before an episode of back pain than at other times in the preceding couple days. A distant second, “manual tasks” were generally risky, but an “awkward posture” tops the list and was notably a more significant risk factor than things like heavy or awkward loads.

Some other noteworthy results:

original abstractAbstracts 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.

OBJECTIVE: To investigate a range of transient risk factors for an episode of sudden-onset, acute low back pain (LBP).

METHODS: This case-crossover study recruited 999 subjects with a new episode of acute LBP between October 2011 and November 2012 from 300 primary care clinics in Sydney, Australia. Each participant was asked to report exposure to 12 putative triggers over the 96 hours preceding the onset of back pain. Conditional logistic regression was used to estimate odds ratios (ORs) expressing the magnitude of increased risk with exposure to each trigger.

RESULTS: Exposure to a range of physical and psychosocial triggers significantly increased the risk of a new onset of LBP; ORs ranged from 2.7 (moderate or vigorous physical activity) to 25.0 (distracted during an activity or task). Age moderated the effect of exposure to heavy loads and sexual activity. The ORs for heavy loads for people ages 20, 40, or 60 years were 13.6, 6.0, and 2.7, respectively. The risk of developing back pain was greatest between 7:00 AM and noon.

CONCLUSION: Transient exposure to a number of modifiable physical and psychosocial triggers substantially increases risk for a new episode of LBP. Triggers previously evaluated in occupational injury studies, but never in LBP, have been shown to significantly increase risk. These results aid our understanding of the causes of LBP and can inform the development of new prevention approaches.

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One article on cites Steffens 2015 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: