Orthopedics · Medical Literature
Safety and Effectiveness of Different Approaches for Epidural Steroid Injections in Lumbar Spinal Stenosis: A Systematic Review and Meta-Analysis.
Abstract
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.
Clinical relevance
Among adults with lumbar spinal stenosis, which epidural steroid injection approach — interlaminar, caudal, or transforaminal — provides the greatest effectiveness and longest duration of pain relief and functional improvement? __SNAPSHOT__ {"studyDesign":"Systematic review and meta-analysis of clinical trials","setting":"Multi-database search (PubMed, Google Scholar, ScienceDirect, CINAHL, EMBASE, OVID); clinical trials from any setting published January 2000 – December 2025","sampleSize":"Not reported in available abstract","population":"Adults with lumbar spinal stenosis (including lumbar canal stenosis and lumbar foraminal stenosis) who underwent epidural steroid injection; specific inclusion criteria beyond diagnostic label not fully reported in available truncated abstract","intervention":"Epidural steroid injections (ESIs) via interlaminar, caudal, or transforaminal approaches","comparator":"Head-to-head comparisons among ESI approaches (interlaminar vs. caudal vs. transforaminal); active or sham comparators within included trials not fully specified in available abstract","primaryOutcome":"Effectiveness (pain relief and functional improvement) and duration of benefit from ESIs; specific instruments (e.g., VAS, NRS, ODI, RMDQ) and timepoints not reported in available truncated abstract","followUp":"Not reported in available abstract","fundingSource":"Not reported"}
Key findings
Quantitative findings — including pooled effect sizes, standard mean differences, confidence intervals, p-values, and NNT/NNH values — are not reported in the available truncated abstract. The study aimed to determine the optimal ESI route for pain relief and functional outcomes in lumbar spinal stenosis, comparing interlaminar, caudal, and transforaminal approaches, but specific comparative results cannot be summarized from the abstract as provided. No adverse event data are reported in the available text. Any numerical summary here would constitute fabrication and is therefore withheld per evidence-based reporting standards.
Practice implications
IMPORTANT LIMITATION: Only a truncated abstract is available; the full results, conclusions, and methodological details of this meta-analysis (PMID 42550520, Wilderman et al., Pain Physician, August 2026) have not been retrieved. What the study appears to have investigated: whether a standardized, evidence-based preference among interlaminar, caudal, and transforaminal ESI routes can be established for lumbar spinal stenosis — a question the prior literature has not resolved. The broader evidence base contextualizes the gap this study addresses: existing systematic reviews (including the 2025 AAN guideline review) demonstrate that ESIs offer at best modest short-term benefit in lumbar spinal stenosis, primarily for disability rather than pain, with insufficient evidence for long-term effects. Whether this 2026 meta-analysis establishes route superiority, confirms prior uncertainty, or identifies a specific subgroup for whom one approach is preferred cannot be determined from the truncated abstract. Clinicians should access the full publication before applying any specific route recommendation to practice. The population to whom findings apply (e.g., central vs. foraminal stenosis, operative vs. non-operative candidates, severity thresholds) is not characterizable from the available text. __LIMITATIONS__ 1. Only a truncated abstract is available; results, risk-of-bias assessments, and conclusions cannot be evaluated. 2. The search was limited to clinical trials from 2000–2025 in six databases, which may introduce selection bias if relevant evidence lies outside these parameters. 3. Studies included appear to vary in ESI protocols (dosing, steroid agent, fluoroscopic vs. non-fluoroscopic guidance, injection frequency), a known source of heterogeneity in this literature. 4. Exclusion of studies without a consistent protocol likely narrows the evidence base but may improve internal validity. 5. Lumbar spinal stenosis is a heterogeneous condition (central, foraminal, lateral recess; single-level vs. multilevel; with or without spondylolisthesis), and pooling across subtypes without stratification risks obscuring clinically important subgroup differences. 6. Surrogate and subjective pain/function endpoints vary widely across trials in this area, limiting cross-study comparability. 7. Sample size of the overall meta-analysis and of individual arms is not reported. 8. Funding source is not reported, precluding conflict-of-interest assessment. 9. Follow-up duration across included trials is not specified in the abstract, preventing evaluation of durability of effect. __BOTTOM_LINE_CATEGORY__ low_certainty __BOTTOM_LINE__ This systematic review and meta-analysis (Wilderman et al., Pain Physician, 2026) evaluates the comparative effectiveness and safety of interlaminar, caudal, and transforaminal ESI approaches for lumbar spinal stenosis, a clinically important but unresolved question given the absence of standardized practice. Quantitative results are unavailable from the truncated abstract, and the full publication must be reviewed before any route-specific recommendation can be adopted. Clinicians should interpret this study in the context of the established modest short-term evidence for ESIs in lumbar spinal stenosis, with no confirmed long-term benefit for pain, as demonstrated by recent high-quality reviews.