The Short-Term Outcome of Transforaminal Epidural Steroid Injection in Patients with Radicular Pain Due to Foraminal Stenosis from Lumbar Isthmic Spondylolisthesis.

After TFESI, chronic radicular pain was significantly reduced regardless of IS severity, and its effect persisted for at least 2 months. However, its effect was superior when the vertebra slippage by IS was less than 25% compared to patients with 25%-50%.