Objective: To determine the therapeutic effect of transforaminal epidural injections in patients with refractory lumbar radicular pain.

Method: Thirty-five patients with lumbar radicular pain who did not receive any other interventional procedures were studied. Transforaminal epidurograms and epidural steroid injections via eighty-nine intervertebral foramens were performed under C-arm fluoroscopic visualization. After confirmation of proper needle placement, 20∼40 mg of triamcinolone and 1 cc of 2% lidocaine hydrochloride were injected into each safe triangle of the intervertebral foramen. Patients were evaluated for visual analogue scale (VAS) and straight leg raising (SLR) test at pre-injection, 1 week post-injection and 3 months post-injection. Changes over time were assessed statistically using ANOVA.

Results: The averages of VAS reduced significantly (p＜0.05) from 5.6⁑1.8 at pre-injection, to 3.5⁑1.7 at 1 week pos-tinjection, to 2.1⁑2.0 at 3 months post-injection, respectively. The averages of SLR augmented significantly (p＜0.05) from 51.6^o⁑16.7^o at pre-injection, to 66.6^o⁑16.0^o at 1 week post-injection, to 77.2^o⁑15.1^o at 3 months post-injection, respectively. Twenty-six out of thirty-five patients (74.3%) had a successful long-term outcome, reporting at least an over 50% reduction between pre-injection and 3 months post-injection in VAS.

Conclusion: Transforaminal epidural injection is an effective treatment for patients with lumbar radicular pain when evaluated after 1 week and 3 months post-injection.