Comparison of Unilateral and Bilateral Transforaminal Epidural Steroid Injections in Unilateral Lumbar Disc Herniation: A Randomized Controlled Trial

<b>Objective:</b> To compare the efficiency of unilateral and bilateral transforaminal epidural steroid injections (TFESI) in patients with unilateral lumbar disc herniation (LDH). <b>Methods:</b> In this prospective randomized single-blinded study, patients with unilateral LDH were randomly divided into two groups: A unilateral TFESI group; and a bilateral TFESI group. The severity of pain and disability were assessed with the Numeric Rating Scale (NRS-11) and Oswestry Disability Index (ODI) at baseline, 1 week, 1 month, and 3 months after interventions. Treatment response was defined as ≥50% reduction in the NRS-11 at the 3-month follow-up. Changes in medication consumption at 3 months following the interventions were recorded. This study protocol is registered at ClinicalTrials.gov (NCT06240793). <b>Results:</b> A total of 104 patients were included in the study (n = 58 in the unilateral TFESI group and n = 46 in the bilateral TFESI group). The NRS-11, ODI scores and medical treatment consumption did not differ statistically between the groups at 3 months (<i>p</i> ˃ 0.05). At 3 months, the rates of patients with a > 50% decrease in NRS-11 scores were 13.8% and 32.6% in the unilateral TFESI group and bilateral TFESI group, respectively. <b>Conclusions:</b> Unilateral and bilateral TFESI both decrease pain severity and disability scores to a similar degree, although bilateral TFESI was more effective in reducing pain severity by over 50% in patients with single-level unilateral LDH.