Transforaminal Epidural Steroid Injection in Elderly and High-Risk Patients: Clinical Outcomes and the Role of Neutrophil/Lymphocyte Ratio as a Predictive Marker

Aim: Transforaminal epidural steroid injection (TFESI) is increasingly used for patients at high risk for invasive surgery. This study evaluated TFESI’s efficacy on functional recovery and examined how advanced age, comorbidities, and neutrophil-to-lymphocyte ratio (NLR) affect clinical outcomes.Material and Methods: This retrospective study included 100 patients with lumbar disc herniation, spinal stenosis, or foraminal narrowing who underwent unilateral TFESI. Oswestry Disability Index (ODI) and Numerical Pain Rating Scale (NPRS) scores were recorded before treatment and at 1, 3, and 6 months post-procedure. Patients were grouped by age (<65 and ≥65 years). Comorbidities, NLR, and pathology level (single/multilevel) were analyzed. Statistical tests used were Friedman, Wilcoxon with Bonferroni correction, Mann-Whitney U, and Kruskal-Wallis.Results: Significant functional improvement and pain reduction occurred early post-TFESI (p<0.001). Younger patients (<65 years) showed faster and greater improvement, while older patients (≥65 years) improved more slowly but significantly. Comorbidities did not significantly affect outcomes. Multilevel pathology and older age were linked to slower recovery. Patients with NLR ≥2.3 had significantly better ODI scores at 6 months (p=0.046).Conclusion: TFESI is a safe and effective treatment even for elderly patients, providing meaningful functional gains despite slower recovery. Multilevel degeneration and comorbidities may hinder recovery speed, whereas NLR could serve as a biological marker predicting treatment response. Beyond pain relief, TFESI aids surgical decision-making and personalized management in complex lumbar diseases.