Comparative Efficacy and Safety of Fluoroscopy-guided Caudal Epidural Steroid Injection and Transforaminal Epidural Steroid Injection for Unilateral L5-S1 Paracentral Discogenic Radicular Pain.

Epidural steroid injection (ESI) is one of the key management strategies in the management of discogenic radicular pain. This study aims to compare the efficacy and safety of fluoroscopy-guided ESI through caudal (cESI) and transforaminal (tfESI) routes for unilateral paracentral L5-S1 discogenic radicular pain. This prospective non-randomized comparative study conducted between January 2023 and January 2024 in a tertiary care hospital included patients presenting with unilateral paracentral L5-S1 discogenic radicular pain who failed 6 weeks of conservative care. The pain and functional outcome was analyzed using numerical pain rating scale (NPRS) and Oswestry disability index, respectively, at baseline, 3-week, 6-week, and 6-month post-intervention. Procedure failure is defined as NPRS score improvement <50% or ODI improvement <40% of baseline. Other outcomes analyzed were the duration of the procedure, and fluoroscopy shots used during the procedure. We enrolled 60 patients in the study, 54 patients were available till the final follow-up with 26 patients in the cESI group and 28 patients in the tfESI group. The mean age of the cESI group (M: F 12:14) and tfESI group (M:F 10:18) was 36.1 (±4.1) years and 38.9 (±3.9) years, respectively. The pain and functional scores were significantly reduced compared to the baseline scores in both the groups (P < 0.001) and the reduction between the two groups was comparable at every follow-up. The tfESI group experienced significantly more failures (n = 8) at 6 months compared to the cESI group (n = 2) (P = 0.048). The tfESI group had significantly longer mean procedure time (18.8 min) and more fluoroscopy usage (16 shots) compared to cESI group with mean procedure time of 13 min (P = 0.014) and fluoroscopy usage of 10 shots (P = 0.023), respectively. No major adverse events were reported for either of the groups. cESI is a simple, safe, and efficacious technique comparable to tfESI in the management of unilateral L5-S1 paracentral discogenic radicular pain with significantly less procedural time and fluoroscopy usage. Further, large-scale studies are needed to validate the study results.