Comparative outcomes of epidural steroids versus placebo after lumbar discectomy in lumbar disc herniation: a systematic review and meta-analysis of randomized controlled trials

Treatment for lumbar disc herniation after failed conservative treatment is discectomy. Discectomy can significantly relieve back pain as well as radicular symptoms. However, many patients with lumbar discectomy experience moderate-to-severe back pain and radicular leg pain. The results of application of epidural steroids (ES) for pain management after lumbar discectomy have previously been inconclusive. We have conducted a systematic review and meta-analysis aims to compare outcomes (efficacy and complications) of epidural steroid application and placebo after discectomy in lumbar disc herniation. This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Relevant studies that reported visual analog scale of back and leg pain, morphine consumption, hospital stay and post-operative complications of either group were identified from Medline and Scopus from the date of inception to 28 October 2017. A total of 12 studies were pooled and analysed, with nine studies having undergone conventional discectomy and three studies having undergone minimally invasive surgery (MIS) discectomy. Overall, there were 1006 patients (502 in the ES group and 504 in the placebo group) included. The unstandardized mean difference of VAS of back pain at 1 week and 1 month, leg pain at 1 week and 1 month, morphine consumption and hospital stay was − 0.53 (95% CI − 1.42, 0.36) score, − 0.89 (95% CI − 1.36, − 0.42) score, − 0.63 (95% CI − 0.75, − 0.50) score, − 0.47 (95% CI − 0.78, − 0.15) score, − 8.47 (95% CI − 16.16, − 0.78) mg and − 0.89 (95% CI − 1.49, − 0.30) days lower when compared to placebo after lumbar discectomy in patients with lumbar disc herniation. A total of ten studies compared the ratio of complication between the ES and placebo groups. No significant differences were noted for complications within the two groups (0.92; 95% CI 0.47, 1.83). This meta-analysis analysed lower back and leg pain, morphine consumption and hospital stay, with no significant difference in complications for ES application after lumbar discectomy in lumbar disc herniation. In terms of surgical approaches with MIS compared to conventional approach, this review demonstrates that ES can reduce post-operative morphine consumption when the surgical approach is conventional, but not for MIS.