How do we stand? Variations during repeated standing phases of asymptomatic subjects and low back pain patients
Four pages on PainSci cite Schmidt 2018: 1. Does Posture Matter? 2. The Complete Guide to Low Back Pain 3. Ten Trillion Cells Walked Into a Bar 4. Spinal curvature chaos
PainSci notes on Schmidt 2018:
We rarely stand quite the same way twice in a row — so good luck identifying a poor posture. In a 2018 experiment, researchers measured and re-measured lumbar spinal curvature (lordosis) in hundreds of people using a handy curve-o-meter, and found that it changed from one test to the next to a surprising degree … and continued to do so with repeat tests. Measure a spine five times in a row, get a wide variety of results!
And there was no difference between spinal position in 350 people versus 80 with back pain. And there was also no difference between athletes and non-athletes. Age, gender, height, and weight made no difference either. In everyone, standing posture was “highly individual and poorly reproducible.” Which is one major reason why posture assessments is just nonsense. It’s unreliable even using an objective measuring gadget — never mind when you introduce the biased eyeballing of a trainer or massage therapist looking for postural trouble to shoot.
See MassageFitnessMag.com for a more detailed analysis.
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.
An irreproducible standing posture can lead to mis-interpretation of radiological measurements, wrong diagnoses and possibly unnecessary treatment. This study aimed to evaluate the differences in lumbar lordosis and sacrum orientation in six repetitive upright standing postures of 353 asymptomatic subjects (including 332 non-athletes and 21 athletes - soccer players) and 83 low back pain (LBP) patients using a non-invasive back-shape measurement device. In the standing position, all investigated cohorts displayed a large inter-subject variability in sacrum orientation (∼40°) and lumbar lordosis (∼53°). In the asymptomatic cohort (non-athletes), 51% of the subjects showed variations in lumbar lordosis of 10-20% in six repeated standing phases and 29% showed variations of even more than 20%. In the sacrum orientation, 53% of all asymptomatic subjects revealed variations of>20% and 31% of even more than 30%. It can be concluded that standing is highly individual and poorly reproducible. The reproducibility was independent of age, gender, body height and weight. LBP patients and athletes showed a similar variability as the asymptomatic cohort. The number of standing phases performed showed no positive effect on the reproducibility. Therefore, the variability in standing is not predictable but random, and thus does not reflect an individual specific behavioral pattern which can be reduced, for example, by repeated standing phases.
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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:
- Topical glyceryl trinitrate (GTN) and eccentric exercises in the treatment of mid-portion achilles tendinopathy (the NEAT trial): a randomised double-blind placebo-controlled trial. Kirwan 2024 Br J Sports Med.
- Placebo analgesia in physical and psychological interventions: Systematic review and meta-analysis of three-armed trials. Hohenschurz-Schmidt 2024 Eur J Pain.
- Recovery trajectories in common musculoskeletal complaints by diagnosis contra prognostic phenotypes. Aasdahl 2021 BMC Musculoskelet Disord.
- Cannabidiol (CBD) products for pain: ineffective, expensive, and with potential harms. Moore 2023 J Pain.
- Moderators of the effect of therapeutic exercise for knee and hip osteoarthritis: a systematic review and individual participant data meta-analysis. Holden 2023 The Lancet Rheumatology.