Response predictors for lumbar epidural steroid injection outcomes for radiculopathy: a retrospective study.

INTRODUCTION

Epidural steroid injections (ESIs) are commonly used for lumbosacral radicular pain, but clinical outcomes remain variable.

OBJECTIVE

This study aimed to identify predictive factors and determine short-term patient-reported outcomes in an understudied Southeast Asian population.

METHODS

A retrospective study involving 198 patients with chronic lumbosacral radicular pain undergoing lumbar ESI was conducted. Treatment success was defined as a ≥30% reduction in the Brief Pain Inventory worst pain score at 4-week follow-up. At follow-up, 167 patients had complete data and were categorized as responders (n = 83) or nonresponders (n = 84). Multivariable binary logistic regression was performed using observed complete-case data to identify factors associated with treatment success.

RESULTS

The observed 4-week response rate was 49.7%. In multivariable analysis, previous spine surgery was associated with lower odds of treatment success (adjusted odds ratio [aOR] 0.30, 95% confidence interval [CI] 0.11-0.80, P = 0.016), whereas unilateral transforaminal ESI (TFESI) was associated with higher odds of response compared with bilateral TFESI (aOR 3.16, 95% CI 1.23-8.13, P = 0.017). Baseline current pain intensity showed a negative direction of association but did not reach statistical significance (aOR 0.86, 95% CI 0.73-1.02, P = 0.086). Specific MRI findings were not significantly associated with clinical outcomes.

CONCLUSION

Clinical history and treatment context were more informative than MRI findings for estimating short-term lumbar ESI response. Prior spine surgery was associated with poorer response, whereas unilateral TFESI was associated with higher odds of short-term treatment success.