Effectiveness of Transforaminal, Interlaminar, and Caudal Epidural Injections in Lumbosacral Disc Herniation: A Systematic Review and Network Meta-analysis.

BACKGROUND

Epidural injection (EI) has been used to manage lower back and radicular leg pain caused by a herniated lumbar disc. There are 3 types of EI techniques currently being used: transforaminal (TFEI), interlaminar (ILEI), and caudal epidural injections (CEI).

OBJECTIVES

To evaluate the comparative effectiveness of TFEI, ILEI, and CEI in reducing pain and improving function in patients with HLD.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

The PubMed, Embase, Cochrane Library, and Scopus databases were searched from the earliest records up to August 2022 for randomized controlled trials (RCTs) and non-RCTs. The standard mean differences (SMDs) in the changes in the Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) scores were calculated from one week through one month posttreatment (short-term) and from 4 months through 6 months posttreatment (long-term).

RESULTS

In total, 11 studies comprising 1,050 patients were included. Network meta-analysis showed that the improvement in the VAS scores was better with TFEI than with CEI (SMD = -1.16, 95% CI = -2.10 to -0.23). Ranking probability analysis showed that TFEI had the highest probability of being the best treatment for reducing pain and improving function in the short- and long-term evaluation periods.

LIMITATIONS

Only a small number of previous studies were included in our analysis. Also, subgroup analysis according to the injection volume, material type, or pain onset could not be conducted.

CONCLUSIONS

TFEI had the best potential of the 3 EI techniques to reduce pain and improve function in patients with a herniated lumbar disc. Further qualified trials comparing the effects of these 3 techniques are warranted to derive definitive conclusions.