Fluoroscopy-Guided Versus Fluoroscopy-Confirmed Ultrasound-Guided S1 Transforaminal Epidural Injection with Pulsed Radiofrequency: A Prospective, Randomized Trial

OBJECTIVE: The aim of this prospective randomized controlled study was to compare the effectiveness and accuracy of the ultrasound- and fluoroscopy-guided S1 transforaminal epidural injection combined with pulsed radiofrequency in patients with lumbosacral radicular pain caused by S1 nerve involvement. MATERIALS AND METHODS: A total of 60 patients were randomized into 2 groups. Patients received S1 transforaminal epidural injection combined with pulsed radiofrequency under either ultrasound or fluoroscopy guidance. Primary outcomes were estimated with Visual Analog Scale scores at 6 months. Secondary outcomes included Oswestry Disability Index, Quantitative Analgesic Questionnaire, and patient satisfaction scores during the 6-month follow-up period and procedure-related variables including procedure time and accuracy of the needle replacement. RESULTS: Both techniques provided significant pain reduction and functional improvement for 6 months compared to baseline (P < .001), without statistical significance between groups at each follow-up point. There was no significant difference in pain medication consumption (P = .441) and patient satisfaction scores (P = .673) between groups. The fluoroscopy guidance for combined transforaminal epidural injection with pulsed radiofrequency at S1 provided a greater accuracy for the cannula replacement (100%) than the ultrasound (93.3%), without significant difference between groups (P = .491). CONCLUSION: The ultrasound-guided combined transforaminal epidural injection with pulsed radiofrequency at S1 level is a feasible alternative to fluoroscopy guidance. In this study, we reported that the ultrasound-guided technique resulted in similar treatment benefits including improvement in pain intensity and functionality and reduction in pain medication consumption as those in the fluoroscopy group, while reducing the risk for radiation exposure.