RESUMEN
The purpose of this study was to compare clinical outcomes after preganglionic versus ganglionic epidural steroid injection (ESI) using a systematic review and network meta-analysis. A systematic review and meta-regression was performed to compare postoperative outcomes between the two difference injection techniques. Relevant randomized controlled trials were identified from Medline and Scopus up to September 24, 2016. Sixteen out of 598 studies were eligible; 3, 2, and 3 studies were included in the pooling of outcomes including effectiveness, visual analog score (VAS), and complications (nerve root, injury, dural puncture, and intraneural injection). Preganglionic ESI has a 2.38 (95% CI 1.12, 5.04) times statistically significantly higher chance of effectiveness when compared to ganglionic ESI. There were differences in pain VAS and complications in lumbar radiculopathy, but these displayed no statistical significance. This meta-analysis indicated that preganglionic ESI has a statistically significantly higher chance of effectiveness when compared to ganglionic ESI. In terms of pain score and complications, there were no statistically significant differences between the two groups. These results were generally homogeneous and with little publication bias, thus should be generalizable.