Reliability and validity of a new clinical test for assessment of the sacroiliac joint dysfunction.

Background: Dysfunctional sacroiliac joint (SIJ) has been cited as a source of low backache (LBA). Numerous non-invasive clinical tests are available for its assessment having poor validity and reliability which challenges their clinical utility. Thus, introduction of a new clinical test may be necessary.

Objective: To assess reliability and validity of a new clinical test for the assessment of patients with SIJ movement dysfunction.

Methods: Forty-five subjects (23 having LBA of SIJ origin and 22 healthy asymptomatic volunteers) with mean age 28.62 $+∕-$ 5.26 years were assessed by 2 blinded examiners for 3 different clinical tests of SIJ, including the new test. The obtained values were assessed for reliability by intraclass correlation, kappa coefficient and percentage agreement. Validity was assessed by averaging sensitivity and specificity. Positive and negative predictive values and accuracy were assessed.

Results: The new test demonstrates good intra- $(r=0.81)$ and inter-rater $(r=0.82)$ reliability with substantial agreement between raters $(k>0.60)$ . It has 79.9% validity, 82% sensitivity, 77% specificity, 79% positive-predictive, 80% negative-predictive value and accuracy.

Conclusion: The new "Shimpi Prone SIJ test" has a good intra- and inter-rater reliability with a substantial rater agreement and a good validity and accuracy for the assessment of patients with SIJ movement dysfunction.