Safety and Effectiveness of Different Approaches for Epidural Steroid Injections in Lumbar Spinal Stenosis: A Systematic Review and Meta-Analysis.
Wilderman Igor I, Sarzetto Francesca F, Didari Tina T, Manor Rotem Frish RF et al.
Lumbar canal stenosis is a common degenerative disorder that causes pain and functional alterations. Epidural steroid injections (ESIs) are often used to treat the symptoms of this condition; however, treatment protocols can vary significantly, and no standardized practice for the management of lumbar canal stenosis has been established. To identify the optimal method of administration for maximizing the effectiveness and duration of pain relief and functionality improvements provided by ESIs. Systematic review and meta-analysis. We searched PubMed, Google Scholar, ScienceDirect, CINAHL, EMBASE, and OVID for clinical trials published from January 2000 to December 2025 that examined the effectiveness of different ESI protocols to ameliorate pain and functionality in spinal stenosis patients. The search terms included ("lumbar spinal stenosis" OR "lumbar canal stenosis" or "lumbar foraminal stenosis") AND "epidural steroid/corticosteroid injection(s)" AND ("interlaminar" OR "caudal" OR "transforaminal" OR "route"). Studies that met exclusion criteria were those that did not use human patients, that were not focused on lumbar stenosis, that had no consistent protocol, or did not express their outcomes as decreases in pain intensity. The risk of bias was assessed with the Cochrane RoB2 tool. We conducted a meta-analysis on the data from individual groups extracted from different studies, including sub-group and meta-regression analyses, to identify variables with significant effects. In total, 33 groups (comprising 1,350 patients) were extracted from 24 studies, with results from one week to 12 months after the injection. Most studies reported significant pain relief up to 3 months from the injections, and some reported that such pain relief persisted even after a year. Of all the factors that influenced the results, the type of steroid used had the greatest effect, with betamethasone providing the greatest and more prolonged relief. Triamcinolone and methylprednisolone offered similar initial levels of pain relief, though it decreased more rapidly, whereas dexamethasone showed the lowest level of benefits. Moreover, the pain relief effect was significantly weaker in patients with severe stenosis, and functionality improvements were also limited in patients with moderate/severe stenosis. In contrast, route of administration (transforaminal, interlaminar, or caudal), dose size, and other parameters showed no significant differences. Most groups included in the analysis were small, with 22 of the 33 (66.7%) having fewer than 50 patients, and only one group including more than 100. Furthermore, the results overall were significantly heterogeneous, and the follow-up times varied, meaning that some subgroups had only one result or none whatsoever at certain time points and limiting the subgroup analysis. ESIs are an effective treatment for the pain caused by spinal stenosis; betamethasone, even at a low dose, appears to provide the greatest benefits, whereas dexamethasone seems the least effective. Patients with mild or moderate stenosis are more likely to experience positive results from ESIs, and the administration route can be chosen depending on the patient's status, offering similar effects. The transforaminal route is likely more beneficial in single-level stenosis, while interlaminar (at the level of maximal stenosis or one caudad) and caudal injections are more appropriate for multilevel pathologies.