A multitest regimen of pain provocation tests as an aid to reduce unnecessary minimally invasive sacroiliac joint procedures.

Abstract

To compare the diagnostic accuracy of a multitest regimen of 5 sacroiliac joint (SIJ) pain provocation tests with fluoroscopically controlled double SIJ blocks using a short- and long-acting local anesthetic in order to reduce the exposure of patients to unnecessary invasive SIJ procedures. Prospective, observational study. Hospital setting. Sixty patients with chronic low back pain. Not applicable. Visual analog scale score and receiver operating characteristic (ROC) curve. Twenty-seven patients responded positively to the blocks, of whom 23 were found positive after the multitest regimen and 4 were negative. For the nonresponders (n=33), these figures were 7 positive and 26 negative. The calculated sensitivity and specificity were .85 (95% confidence interval [CI], .72-.99) and .79 (95% CI, .65-.93), respectively. Positive and negative predictive values were .77 (95% CI, .62-.92) and .87 (95% CI, .74-.99), respectively. The positive likelihood ratio was 4.02 (95% CI, 2.04-7.89); the negative likelihood ratio was .19 (95% CI, .07-.47). The area under the ROC curve was .799. The test regimen with 3 or more positive tests is indicative of SIJ pain. It can be used in early clinical decision making to reduce the number of unnecessary minimally invasive diagnostic SIJ procedures.