Comparison of the Oblique Interlaminar and Transforaminal Lumbar Epidural Steroid Injections for Treatment of Low Back and Lumbosacral Radicular Pain

BACKGROUND: Transforaminal epidural steroid injections (TF-ESIs) effectively deliver small amounts of drugs to inflamed sites via the ventral epidural space. However, there is a high risk of nerve damage as the needle narrowly approaches the spinal nerve. Therefore, we devised an oblique interlaminar (OIL) approach as an alternative method. We compared the efficacy of fluoroscopic-guided OIL-ESIs with that of TF-ESIs in the management of lower back and unilateral lumbosacral radicular pain. MATERIALS AND METHODS: Sixty-six patients were randomized to receive a fluoroscopic-guided ESI either through the OIL (n = 33, group OIL) or TF (n = 33, group TF) approach. They were evaluated for effective pain relief using the visual analogue scale (VAS) and for functional improvement using the Oswestry Disability Index (ODI) and Roland Morris Disability Questionnaire (RMDQ). Other outcome measures were the presence of ventral and contralateral spread of contrast, patients’ satisfaction, and adverse events. RESULTS: There were no significant differences between the groups in the VAS, ODI, and RMDQ scores during the 12-week period. The differences in the ODI and RMDQ scores before and after the treatment were higher in group TF than in group OIL. The contralateral spread of contrast was higher in group OIL than in group TF. There were no significant differences in the other outcomes between the groups. CONCLUSION: ESIs delivered through the OIL approach are equally effective in pain relief and functional improvement as those delivered via the TF approach in the management of low back and unilateral lumbosacral radicular pain.