[Lumbar epidural steroid injection: Is the success rate predictable?].

Objectives: The aim of this study was to determine the relation between the percent of canal compromise and success rate of epidural steroid injection (ESI) in patients with symptomatic lumbar herniated intervertebral discs.

Methods: Patients with lumbar herniated intervertebral disc suffering from leg pain and treated with ESI were selected. The axial magnetic resonance (MR) image showing the largest canal compromise by the herniated disc was selected for measurements.