Lack of Superiority of Epidural Injections with Lidocaine with Steroids Compared to Without Steroids in Spinal Pain: A Systematic Review and Meta-Analysis

Abstract

Background: Multiple randomized controlled trials (RCTs) and systematic reviews have been conducted to summarize the evidence for administration of local anesthetic (lidocaine) alone or with steroids, with discordant opinions, more in favor of equal effect with local anesthetic alone or with steroids.

Objective: To evaluate the comparative effectiveness of lidocaine alone and lidocaine with steroids in managing spinal pain to assess superiority or equivalency.

Study design: A systematic review of RCTs assessing the effectiveness of lidocaine alone compared with addition of steroids to lidocaine in managing spinal pain secondary to multiple causes (disc herniation, radiculitis, discogenic pain, spinal stenosis, and post-surgery syndrome).

Methods: This systematic review was performed utilizing Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) for literature search, Cochrane review criteria, and Interventional Pain Management Techniques-Quality Appraisal of Reliability and Risk of Bias Assessment (IPM-QRB) to assess the methodologic quality assessment and qualitative analysis utilizing best evidence synthesis principles, and quantitative analysis utilizing conventional and single-arm meta-analysis. PubMed, Cochrane Library, US National Guideline Clearinghouse, Google Scholar, and prior systematic reviews and reference lists were utilized in the literature search from 1966 through December 2019. The evidence was summarized utilizing principles of best evidence synthesis on a scale of 1 to 5.

Outcome measures: A hard endpoint for the primary outcome was defined as the proportion of patients with 50% pain relief and improvement in function. Secondary outcome measures, or soft endpoints, were pain relief and/or improvement in function. Effectiveness was determined as short-term if it was less than 6 months. Improvement that lasted longer than 6 months, was defined as long-term.

Results: Based on search criteria, 15 manuscripts were identified and considered for inclusion for qualitative analysis, quantitative analysis with conventional meta-analysis, and single-arm meta-analysis. The results showed Level II, moderate evidence, for short-term and long-term improvement in pain and function with the application of epidural injections with local anesthetic with or without steroid in managing spinal pain of multiple origins.

Limitations: Despite 15 RCTs, evidence may still be considered as less than optimal and further studies are recommended.

Conclusion: Overall, the present meta-analysis shows moderate (Level II) evidence for epidural injections with lidocaine with or without steroids in managing spinal pain secondary to disc herniation, spinal stenosis, discogenic pain, and post-surgery syndrome based on relevant, high-quality RCTs. Results were similar for lidocaine, with or without steroids.

Keywords: Chronic spinal pain; active control trials; epidural injections; lidocaine; local anesthetic; placebo effect; steroids.