The Role of Temporal Changes in Pain Response After Transforaminal Epidural Steroid Injection on Treatment Success

Transforaminal epidural steroid injection (TFESI) is a commonly used minimally invasive procedure for the treatment of lumbar radicular pain secondary to disc herniation. Although TFESI has been shown to provide significant pain relief in a substantial proportion of patients, the onset, duration, and temporal pattern of pain relief after the procedure vary considerably among individuals. The relationship between early pain response patterns and long-term treatment success remains poorly understood.

This prospective observational study aims to evaluate whether temporal changes in pain intensity following TFESI, particularly during the early post-procedural period, are associated with clinical treatment success at mid- and long-term follow-up. Pain intensity will be assessed using the Numeric Rating Scale (NRS) at predefined time points following the procedure, and treatment success will be defined as a ≥50% reduction in NRS score compared with baseline.