A Multitest Regimen of Pain Provocation Tests As an Aid to Reduce Unnecessary Minimally Invasive Sacroiliac Joint Procedures

Objective: 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.

Design: Prospective, observational study.

Setting: Hospital setting.

Participants: Sixty patients with chronic low back pain.

Interventions: Not applicable.

Main Outcome Measures: Visual analog scale score and receiver operating characteristic (ROC) curve.

Results: 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.

Conclusions: 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.