Comparison of Clinical Efficacy of Epidural Injection With or Without Steroids in the Treatment of Degenerative Disc Disease: Meta-analysis

Background: Selective nerve root block has been widely used to treat degenerative disc disease (DDD), but no detailed research data is provided to compare the efficacy of epidural injection of anesthetics with or without steroids on the DDD treatment.

Objectives: This study aimed to provide the first comparison of steroids + local anesthetic (LA) or LA alone for the treatment of DDD.

Study design: We systematically searched PubMed, Medline, Embase, and Cochrane. A systemic review and meta-analysis were performed to assess the clinical efficacy of both the steroids + LA group and the LA alone group, and subgroup analysis was also adopted.

Setting: A systematic review and meta-analysis using a random effects model on randomized controlled studies (RCTs).

Methods: After reviewing titles, abstracts, risk of bias, and full texts of 15,889 studies that were chosen following removal of duplicates after the initial database search, finally, 19 RCTs were included. Pain rating, functional score, follow-up period, and other-related data were extracted from these included works, and the effect size and statistical significance were calculated by the random effects model. The quality and level of the derived evidence were assessed by means of the Grading of Recommendations Assessment, Development and Evaluation method.

Results: In terms of the Numeric Rating Scale (NRS-11) and Oswestry Disability Index (ODI) at one year, the combination of steroids + LA was obviously superior to LA. Subgroup analysis suggested that the combination of steroids + LA was more effective than LA alone in regard to the ODI in the lumbar group within 2 years. The opioids intake of patients treated by LA alone was less than that of the steroids + LA group within 3 months, and LA alone was more effective in pain score reduction, with more than 50% within 6 months in the interlaminar injection group. However, the combination of steroids + LA was more effective when alleviating the NRS-11 within 18 months in the caudal injection group.

Limitations: Firstly, this analysis was inconsistent in technique, dosage, injection frequency, and follow-up period of epidural injections. Such differences may compromise the reported efficacy. Secondly, adverse reactions arising out of the 2 groups were not examined in that the included RCTs did not provide the data. Thirdly, different injection methods would compromise the outcomes, and no subgroup analysis was performed on different injection methods. Finally, these included articles that were mainly sourced from Manchikanti's team, and thus biased to some extent.

Conclusions: The addition of steroids to anesthetic injectates was associated with a better NRS-11 and ODI compared with LA alone within one year in patients with DDD. Furthermore, the improvement of the ODI was observed within 2 years in patients with lumbar DDD.