Evaluation of the Effectiveness of Lumbar Interlaminar Epidural Injections in Managing Chronic Pain of Lumbar Disc Herniation or Radiculitis: A Randomized, Double-Blind, Controlled Trial

Background: The pathophysiology of lumbar radicular pain is the subject of ongoing research, witha reported prevalence of sciatica or radiculitis ranging from 1.2% to 43%. Among the numerous nonsurgical interventions available, epidural injections are the most commonly performed interventions inthe United States in managing chronic low back and lower extremity pain.Study Design: A randomized, double-blind, controlled trial.Setting: An interventional pain management practice, a specialty referral center, a privatepractice setting in the United States.Objective: To evaluate the effectiveness of lumbar interlaminar epidural injections with localanesthetic, with or without steroids, in managing chronic low back and lower extremity painsecondary to disc herniation or radiculitis in providing effective and long-lasting pain relief.Methods: Patients were assigned to one of 2 groups with local anesthetic only or with localanesthetic mixed with non-particulate betamethasone.Randomization was performed by computer-generated random allocations sequence by simplerandomization. Seventy patients were included in this analysis.Outcomes Assessment: Patient outcomes were measured at baseline, 3, 6, and 12 monthspost-treatment with the Numeric Rating Scale (NRS), the Oswestry Disability Index 2.0 (ODI),employment status, and opioid intake. Decrease of ≥ 50% of NRS scores and Oswestry scoreswere considered significant.Results: Significant pain relief (≥ 50%) was seen at 12 months in 74% of patients in Group Iand 86% in Group II, and 69% and 83% in ODI scores respectively.Significant differences were noted in pain relief characteristics at 6 months between Group I andGroup II (P = 0.001) and functional status improvement was significantly better in Group II at 6months and 12 months (P = 0.019 and 0.045). The overall average procedures per year were 4.3in Group I and 4.2 in Group II with an average total relief per year of 42.2 ± 10.5 weeks in GroupI and 41.4 ± 11.0 weeks in Group II over a period of 52 weeks in the successful group.Limitations: The study limitations include the lack of a placebo group and the fact that this isa preliminary report of 35 patients in each group.Conclusion: Overall, 74% of patients in Group I without steroids and 86% in Group II with steroidswith lumbar disc herniation or radiculitis might benefit from lumbar interlaminar epidural injections.Key words: Chronic low back pain, lower extremity pain, disc herniation, radiculitis, lumbarinterlaminar epidural injections, epidural steroids, local anesthetic