Test library › Low back & pelvis
Passive Lumbar Extension test
For: Lumbar segmental instability
Excess or poorly controlled movement at one level of the low back, thought to provoke pain during movement, for example a painful catch when bending.
Treat with caution (see below)Positive likelihood ratio as published by the authors (from sensitivity 84.2% and specificity 90.4%); sensitivity and specificity shown rounded.
Its negative likelihood ratio reaches the usual rule-out threshold, but the book does not count it as a reliable rule-out test.
Caution: A later study found much lower sensitivity, about 43%, so a negative result may not rule instability out.
What the numbers mean
- Positive result: see the caution above before relying on this result.
- Negative result: see the caution above before relying on this result.
Source
Kasai Y, Morishita K, Kawakita E, Kondo T, Uchida A. A new evaluation method for lumbar spinal instability: passive lumbar extension test. Phys Ther. 2006;86(12):1661–1667. PubMed · single study
Figures as they will appear in Rule It In, Rule It Out (Trokos, forthcoming). If a newer or better study changes them, this page changes with the book. Figures last updated from the book on 2 October 2026.
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This page gives the published figures. Rule It In, Rule It Out adds how to do this test, what counts as positive, how to read the result, and, where studied, whether combining it with other tests helps.
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