Test library › Low back & pelvis
Compression test
For: Sacroiliac joint pain
Pain arising from the sacroiliac joint, where the base of the spine (sacrum) meets the pelvis. Usually felt in the buttock, below the waist, on one side.
A weak test on its ownWhat the numbers mean
- Positive result: a small shift: a positive result nudges the diagnosis up, but does not settle it.
- Negative result: a small shift: a negative result nudges the diagnosis down, but does not exclude it.
Source
Laslett M, Aprill CN, McDonald B, Young SB. Diagnosis of sacroiliac joint pain: validity of individual provocation tests and composites of tests. Man Ther. 2005;10(3):207–218. 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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One study, one test, once a month
Rule It In is a free evidence letter for musculoskeletal clinicians: one recent study explained, one examination test with its real numbers. From Trokos, publisher of Rule It In, Rule It Out.