Comparison of Fluoroscopy and Ultrasound Guidance for Sacroiliac Joint Injection in Patients with Chronic Low Back Pain.

Background and ObjectivesSacroiliac joint (SIJ) arthritis is a common cause of chronic mechanical low back pain (LBP) that is often treated with injection of local anesthetic and steroids. Ultrasound (US) has emerged as a viable alternative to fluoroscopy (FL) to guide SIJ injections; however, few studies have compared these modalities. In this prospective randomized, controlled trial, we compared both accuracy and efficacy of US and FL guidance for SIJ injections. MethodsForty patients with chronic moderate-to-severe LBP secondary to SIJ arthritis were randomized to receive US-or FL-guided unilateral SIJ injections. Primary outcomes included pain at 1month measured by numerical rating scale (NRS) scores. Secondary outcomes included NRS scores at 24hours, 72hours, 1week, and 3months after injection, physical functioning at 1month after the procedure, procedure time, incidence of intra-articular and peri-articular needle placement, patient discomfort, overall patient satisfaction, and daily opioid consumption. ResultsThere was no significant difference in NRS pain scores between the 2 groups at 1month or at any other follow-up points. A significant reduction from baseline mean NRS scores was observed in both groups at 1month after injection (US 22.7%, P=0.025; FL 37.3%, P<0.001). There was no significant difference in procedure-related variables, physical functioning, discomfort, opioid utilization, and patient satisfaction between the 2 groups. ConclusionsUltrasound-guided SIJ injection with fluoroscopic confirmation has similar accuracy and efficacy to fluoroscopy alone for SIJ injections in patients with chronic low back pain secondary to SIJ arthritis.