Pulsed Epidural Radiofrequency Versus Epidural Steroid Injection in Patients With Failed Back Syndrome: The EPIPUL Study

Abstract

Introduction: Persistent post-lumbar pain syndrome (PSPS) type II is a frequent condition in Pain Units, with limited treatment options such as epidural corticosteroids or epidurolysis. Epidural pulsed radiofrequency (PRF) using a catheter has been reported as more effective than transforaminal PRF. This study evaluates the efficacy of epidural PRF with or without corticosteroids in patients with PSPS type II.

Materials and methods: A randomized, controlled, multicentre trial included 131 patients. Participants were allocated to either a control group receiving epidural corticosteroids alone or an experimental group receiving epidural PRF plus corticosteroids. Outcomes were assessed with the Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), DN4 questionnaire, and Patient Global Impression of Improvement (PGI-I) at 1, 2, 4, and 6 months.

Results: Of the 131 patients, 72 were assigned to PRF + steroids and 59 to control. The PRF + steroids group showed significantly greater improvement in VAS (p ≤ 0.002 across follow-ups), ODI (p ≤ 0.004), DN4 (p ≤ 0.015), and PGI-I (p ≤ 0.004) compared with control. Number needed to treat for a 2-3 point reduction in VAS ranged between 2.7 and 2.9. No major complications were observed, and adverse effects were minor and transient.

Conclusions: Epidural PRF combined with corticosteroids provides superior pain relief, functional improvement, and patient satisfaction compared with corticosteroids alone in PSPS type II. This technique appears safe, with no significant complications, and represents a promising minimally invasive option for managing persistent post-surgical lumbar radiculopathy.

Significance statement: This randomized controlled trial provides the first multicentre evidence that epidural pulsed radiofrequency combined with corticosteroids is more effective than corticosteroids alone for persistent spinal pain syndrome type II. The study shows sustained improvements in pain, disability, and patient-reported outcomes with a favourable safety profile, supporting epidural PRF as a valuable therapeutic option for complex post-surgical lumbar pain.

Keywords: chronic pain; epidural space; failed back surgery syndrome; persistent spinal pain syndrome type II (PSPS type II); pulsed radiofrequency treatment; radiculopathy; steroids/therapeutic use; treatment outcome.