The effect of leg length on back pain: a classic test
Eight pages on PainSci cite Grundy 1984: 1. The Complete Guide to Trigger Points & Myofascial Pain 2. Does Posture Matter? 3. The Complete Guide to IT Band Syndrome 4. The Complete Guide to Low Back Pain 5. The Not-So-Humble Healer 6. Are Orthotics Worth It? 7. Your Back Is Not Out of Alignment 8. Reading Guide for Professionals
PainSci commentary on Grundy 1984: ?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 wherever possible.
This classic, elegant experiment found no connection between leg length and back pain. Like most of the really good science experiments, it has that MythBusters attitude: “why don’t we just check that assumption?” Researchers measured leg lengths, looking for differences in “lower limb length and other disproportion at or around the sacroiliac joints” and found no association with low back pain. “Chronic back pain is thus unlikely to be part of the short-leg syndrome.” Other studies since have backed this up, but this simple old paper remains a favourite.
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.
In a case-control study, in which a specially designed questionnaire and a ‘locating jig’ were used to investigate the association between difference in lower limb length and other disproportion at or around the sacroiliac joints and the existence of chronic low back pain, no association was found. Chronic back pain is thus unlikely to be part of the short-leg syndrome.
related content
- “Relationship between mechanical factors and incidence of low back pain,” Nourbakhsh et al, Journal of Orthopaedic & Sports Physical Therapy, 2002.
- “Leg-length discrepancy is associated with low back pain among those who must stand while working,” Rannisto et al, BMC Musculoskeletal Disorders, 2015.
- “Comparison of supine and prone methods of leg length inequality assessment,” Cooperstein et al, J Chiropr Med, 2017.
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.