03:54 PM Abstract No. 302 CT-guided sacroiliac (SI) joint injection for SI joint instability

Abstract

To evaluate the outcomes after computed tomography (CT)-guided sacroiliac (SI) joint injections in patients suspected to have lower back pain from SI joint instability. For this retrospective study, 44 patients with difficult anatomy were referred to IR for CT SI joint injection between January 2017 and March 2018. These patients were seen both by orthopedic surgery and interventional radiology and suspected to have sacroiliac joint instability as their cause of lower back pain based on history and physical exam. A thorough chart review was performed to determine the technical success rate and clinical outcomes of CT-guided SI joint injection. We then determine the post-procedural rate of sacroiliac joint fusion with or without recurrent pain, repeat injection, rhizotomy and other surgeries. During the study period, 46 CT-guided SI joint injections were performed on 44 patients. There were 4 technically unsuccessful injections (9%), which ultimately led to other procedures such as lumbar fusion. Of the 42 technically successful procedures (91%), there were 30 (71%) positive results and 12 (29%) negative or no relief in pain. There were 18 patients that underwent SI joint fusion (5 other patients are currently awaiting surgery). 11/18 (61%) patients experienced lasting relief of pain after surgery. 6/11 patients (39%) had recurrence of back pain leading to procedures such as repeat SI joint injections and SI joint rhizotomies. The 12 patients that did not experience pain relief after SI joint injections went on to have other solutions to their back pain including lumbar fusion, facet blocks, and epidural injections. 2/42 (5%) patients experienced lasting relief with SI joint injection alone. There were 4 patients (5 injections) lost to follow up, 3 of which were diagnosed with cancer during the study period. 9 months of follow up data was available for 41/46 (89%) patients. SI joint pain is a difficult diagnosis to make despite evaluation by multiple specialties. As opposed to fluoro SI joint injection, CT SI joint injection provides cross sectional data and can confirm intra-articular placement of the needle to further increase the diagnostic accuracy of the study.