Comparison of Particulate Steroid Injection vs Nonparticulate Steroid Injection for Lumbar Radicular Pain: A Systematic Review and Meta-analysis

Objective: The objective of this study was to identify the difference on pain intensity and disability between particulate and non-particulate steroid injections in patients with lumbar radicular pain. Subgroup analysis by study design, type of particulate steroid, and follow-up duration were performed. Data Sources: We performed the literature search in the PubMed, Embase, and Cochrane Library up March, 2023. Study Selectionː Studies, including randomized controlled trials (RCTs) and nonrandomized studies, that compared particulate steroid injection and non-particulate steroid injection in patients with lumbar radicular pain were independently reviewed by two reviewers for eligibility for inclusion. Data extractionː Outcomes of interest were pain intensity and disability. Two reviewers independently assessed the quality of included studies using the revised Cochrane Risk of Bias (RoB2.0) tool for RCTs and the Risk of Bias in Non-Randomized Studies of Interventions Tool (ROBINS-I) for nonrandomized studies. Effect sizes were estimated using mean difference (MD) and standardized mean difference (SMD). Data synthesisː Total 10 studies were included in this meta-analysis. The results showed no significant difference in visual analog scale, disability score and the numbers of patients with 50% pain reduction between particulate and non-particulate steroid injection groups (P > 0.05). Particulate steroid injections showed significant better effect in pain scale in RCTs (MD=0.62; 95% CI 0.08-1.16, P = 0.02). In subgroup analysis with steroid types, methylprednisolone showed better effect compared with dexamethasone, while dexamethasone showed better effect compared with betamethasone. Conclusionsː This meta-analysis suggested no significant differences between the particulate and non-particulate steroid groups in pain or disability score. Therefore, considering the safety profile of non-particulate steroids, non-particulate steroid injection may be helpful in patients with lumbar radicular pain.