Sacroiliac joint: pain referral maps upon applying a new injection/arthrography technique. Part II: Clinical evaluation.

STUDY DESIGN: A pain referral map generated from Part I of this study was tested in 54 consecutive patients. Pain diagrams, completed by each patient, were compared to the map generated from sacroiliac injections in 10 volunteers (Part I). Two clinicians, blinded to the examination of each individual, selected the diagrams most consistent with the pain map.

OBJECTIVES: To determine the applicability of a pain referral map as a screening tool for sacroiliac joint dysfunction.

SUMMARY OF BACKGROUND DATA: Two independent examiners, blinded to the patients' examinations, selected 16 individuals whose pain diagrams most represented the map generated in Part I. There was a 100% concordance of patients selected. All 16 patients selected had a provocation-positive SI joint injection. Ten of these individuals also received lumbar discography and lumbar facet injections. Only the SI injection on the symptomatic side was provocation positive.

METHODS: Patients selected for evaluation based on pain mapping received sacroiliac joint injection. Provocation-positive injections were used to confirm the diagnosis of sacroiliac joint dysfunction. Ten subjects subsequently underwent lumbar discography and lumbar facet joint injections to further confirm the diagnosis.

RESULTS: Few studies involving low back pain have used pain referral maps. In the present study, patients were successfully screened for sacroiliac joint dysfunction using a pain referral map generated from provocation of asymptomatic volunteers.

CONCLUSION: Patients can be successfully screened for sacroiliac joint dysfunction based on comparison with a pain referral map. Further study on the false negative rates of sacroiliac pain maps is needed.