Background Sacroiliac provocation tests are used in cases with a suspected diagnosis of spondyloarthritis (SpA). However, all of the studies on the diagnostic value of these physical examination tests have been carried out in non-inflammatory sacroiliac (SI) joint pathologies, and the data about the contribution of these tests in the diagnosis of SpA is poor.
Objectives To investigate the role of sacroiliac provocation tests in the diagnosis of SpA, and their relation with inflammatory findings in magnetic resonance imaging (MRI).
Methods 51 patients (F/M=7/44) with chronic low back and/or hip pain admitted to the rheumatology clinic were included in the study. The history of patients participating in the study were taken by a rheumatologist, and another experienced rheumatologist who is unaware of the patient's medical information performed 5 different challenge tests for SI joints (sacroiliac compression test, sacroiliac distraction test, FABER-Patrick test, sacral thrust test, drop test) within a certain protocol. All patients were evaluated with sacroiliac MRI for the presence of acute inflammation. The sensitivity, specificity, positive predictive value, negative predictive value, positive and negative likelihood ratio (LR) and diagnostic accuracy of each physical examination methods were calculated with taking clinical diagnosis and sacroiliac MRI as the standard evidence of acute inflammation (2 different comparisons).
Results 30 patients included in the study met the diagnostic criteria for SpA. Calculations related to diagnostic value of each examination method are summarized in Table 1.When data was analyzed for the diagnosis of SpA, the positive LR value of provocation tests ranged between 1.4–2.24.For the relationship between the examination findings and acute changes in SI joint MRI, LR values ranged positively between 1.1–2.79.Inflammatory back pain in history was associated with a positive LR value of 1.17 in predicting the diagnosis of SpA and a positive LR value of 1.37 in predicting acute changes in MRI.
Conclusions These results show that the contribution of SI provocation tests for predicting the findings of inflammation in MRI or SpA diagnosis is extremely limited.When compared to the diagnostic accuracy of similar tests in non-inflammatory conditions of SI joint in the literature, the predictive value of provocation tests in the diagnosis of inflammatory conditions seems to be lower.
Disclosure of Interest None declared