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

BACKGROUND AND OBJECTIVES: Sacroiliac 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.

METHODS: Forty 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 1 month measured by numerical rating scale (NRS) scores. Secondary outcomes included NRS scores at 24 hours, 72 hours, 1 week, and 3 months after injection, physical functioning at 1 month after the procedure, procedure time, incidence of intra-articular and peri-articular needle placement, patient discomfort, overall patient satisfaction, and daily opioid consumption.

RESULTS: There was no significant difference in NRS pain scores between the 2 groups at 1 month or at any other follow-up points. A significant reduction from baseline mean NRS scores was observed in both groups at 1 month 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.

CONCLUSIONS: Ultrasound-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.