One-Year Results of a Randomized, Double-Blind, Active Controlled Trial of Fluoroscopic Caudal Epidural Injections With or Without Steroids in Managing Chronic Discogenic Low Back Pain Without Disc Herniation or Radiculitis

Abstract

Background: Lumbar radicular pain pathophysiology continues to be the subject of research and debate as discogenic pain is increasingly seen as a cause of non-specific low back pain. Among non-surgical methods used to manage chronic low back pain with or without disc herniation, epidural injections are one of the most common modalities. However, there is little evidence utilizing contemporary methodology for using epidural injections in patients with discogenic pain. Study Design: A randomized, double-blind, active-controlled trial. Setting: An interventional pain management practice, a specialty referral center, a private practice setting in the United States. Objectives: To evaluate the effectiveness of caudal epidural injections with local anesthetic, with or without steroids, in managing chronic low back pain without disc herniation or radiculitis. Methods: A total of 120 patients were assigned to one of 2 groups. Group I patients received caudal epidural injections with local anesthetic (lidocaine 0.5% 10 mL); Group II patients received caudal epidural injections with 9 mL of 0.5% lidocaine mixed with 1 mL of steroid (either brand name or non-particulate betamethasone [6 mg] or methylprednisolone [40 mg]. Computer-generated randomization and random allocation sequence by simple randomization were the randomization techniques utilized. Outcomes Assessment: Multiple outcome measures were utilized which included the Numeric Rating Scale (NRS), the Oswestry Disability Index 2.0 (ODI), employment status, functional status, and opioid intake at 3, 6, and 12 months post treatment. Significant pain relief and functional status improvement were described as a 50% or more reduction in scores from baseline. Results: Significant pain relief and functional status improvement were observed in 55% of the patients in Group I and 68% of the patients in Group II. In contrast, 84% of patients in Group I and 85% in Group II saw significant pain relief and functional status improvement in the successful group (62% in Group I and 68% in Group II). The average procedures per year were 3.8 ± 0.9 for Group I and 4.3 ± 0.9 for Group II. Average pain scores decreased from 8.0 ± 0.9 to 4.3 ± 1.79 for Group I and from 7.9 ± 1.0 to 3.8 ± 1.59 for Group II. There were no differences among the patients receiving one of the 3 steroids. Limitations: The results of this study are limited by lack of a placebo group. Conclusion: Caudal epidural injections with local anesthetic with or without steroids are effective in patients with chronic low back pain of discogenic origin without facet joint pain, disc herniation, and/or radiculitis. Clinical Trial: NCT00370799 Key words: Chronic low back pain, lower extremity pain, discogenic pain, facet joint pain, disc herniation, radiculitis, lumbar interlaminar epidural injections, epidural steroids, local anesthetic