A comparison of clinical and procedural outcomes of transforaminal versus parasagittal interlaminar epidural steroid injections for radicular pain secondary to lumbar disc herniation.

Abstract

Background: This study aims to compare the clinical and procedural outcomes of transforaminal epidural steroid injections (TFESIs) and parasagittal interlaminar epidural steroid injections (P-ILESIs) in patients with unilateral radicular pain secondary to lumbar disc herniation (LDH).

Patients and methods: Between January 2024 and June 2025, a total of 162 patients with unilateral radicular pain caused by single-level LDH were included in this retrospective, observational cohort study. The patients were divided into the two groups based on the technique as the TFESI group (n = 82) and the P-ILESI group (n = 80). Pain, disability, sleep quality, and health-related quality of life were assessed using the Numeric Rating Scale (NRS), Oswestry Disability Index (ODI), Pittsburgh Sleep Quality Index (PSQI), and Short Form-12 (SF-12), respectively at baseline, one month, and six months. Fluoroscopy time and cumulative radiation dose were also recorded.

Results: Of the patients, 120 were male and 42 were female with a median age of 47 (range 22 to 65) years. Both techniques significantly improved pain, disability, sleep quality, and quality of life at one and six months (p < 0.001). The reduction in NRS from baseline was greater with TFESI at one month (p = 0.008), but not at six months (p = 0.545). The ODI scores were lower with TFESI at one month, although the magnitude of improvement from baseline did not significantly differ and no difference was observed at six months. Quality of life outcomes were comparable between the groups. The P-ILESI required longer fluoroscopy time and higher radiation exposure than TFESI (p < 0.001 for both). No major complications occurred, and minor adverse events were infrequent and comparable between the groups (p = 0.764).

Conclusion: Both TFESI and P-ILESI appear to be effective and safe approaches for the treatment of radicular pain associated with LDH. The choice of epidural approach should be individualized according to clinical and anatomical considerations, as well as operator experience.