Long-term comparative study between transforaminal and interlaminar epidural injection of steroids in lumbar radiculopathy due to single-level disc herniation

Background: Epidural steroid injection is commonly used in treating radicular pain secondary to lumbar disc prolapse, which is a common clinical condition. Two main techniques were suggested to deliver the steroids: interlaminar and transforaminal injections. Methods: From June 2013 to March 2016 we performed a prospective study on 40 patients between the ages of 19 and 55 yr. All the patients had low back pain and lower limb radiculopathy secondary to a single-level lumbar disc prolapse. The pupose of this study was to compare interlaminar and tranforaminal injection techniques regarding the short-term and long-term improvement of back pain, leg pain, and functional outcomes. On admission the patients were evaluated using a visual analogue scale (VAS) for back and leg pain, and the Oswestry Disability Index (ODI) for functional capacity. They were followed for a period of 47 to 49 wk (mean 48 wk), and clinical and functional outcomes were assessed using the same tools for evaluation. Results: We found that VAS and ODI improved in both the transforaminal and interlaminar groups both short and long term, but the only statistically significant improvement was in VAS for leg pain and the ODI in the transforaminal group. Conclusions: Epidural steroid injection is generally a safe procedure, but the transforaminal approach gives better results than the interlaminar approach in relieving radicular pain and improving functional outcome.