Objective
The goal of this study was to compare the therapeutic and the functional value between translaminar approach and transforaminal approach of epidural steroid injection in patient with refractory radicular pain.

Method
Among 31 patients with unilateral herniated nucleus pulposus (HNP) which was confirmed by physical examination and magnetic resonance imaging (MRI), 17 patients received a transforaminal approach and 14 patients received a translaminar approach. All patients were evaluated by independent observer and were checked by visual analogue scale (VAS), functional score before and 1 day, 2 weeks and 4 weeks after injection.

Results
The VAS of transforaminal approach was significantly lower than that of translaminar approach after 2 weeks and after 4 weeks (p＜0.05), although there were no statistical difference before and 1 day after injection. The functional score of transforaminal approach was significantly higher than that of translaminar approach after 4 weeks (p＜0.05), although there were no statistical difference before and 1 day, 2 weeks after injection. The translaminar approach needs more frequent injection (p＜0.05).

Conclusion
This study suggests that both translaminar approach and transforaminal approach could be valuable to the initial management of refractory radicular pain, but the duration of therapeutic effects was relatively short in translaminar approach. Transforaminal approach will be the promising treatment of refractory radicular pain, because it has better therapeutic efficacy, safety and longer duration of therapeutic effects than translaminar approach.