Clinical Evaluation of Transforaminal Epidural Steroid Injection in Patients with Gadolinium Enhancing Spinal Nerves Associated with Disc Herniation

Background: Transforaminal epidural steroid injection (TFESI) of corticosteroid is frequently employed to mitigate the painful and disabling symptoms of lumbar disc herniation. However, the treatment outcome of TFESI in patients with radicular pain and inflamed neural structures as assessed by contrast-enhanced magnetic resonance imaging (MRI) has not been forthcoming. Objectives: To investigate functional improvement and pain reduction following TFESI in patients found to have nerve inflammation as evidenced by gadolinium-enhanced (MRI). Study Design: Retrospective assessment. Setting: Tertiary spinal intervention center, Daegu, Korea. Methods: Thirty-seven patients were selected by strict inclusion criteria. Patients were classified into enhancing and non-enhancing groups as evidenced by gadolinium-enhanced MRI. The enhancing group was further divided into pre-dorsal roog ganglion (DRG) only enhanced group and pre-DRG and post-DRG enhanced group. Clinical outcomes were evidenced by numeric rating scale (NRS) and Oswestry disability index (ODI) at pretreatment, one week, and 4 weeks after treatment. Results: The improvement of NRS and ODI in the enhanced group was greater than those of the non-enhanced group, at one week and 4 weeks after TFESI (P < 0.05). However there was no significant difference in improvement of NRS and ODI between pre-DRG only enhanced group and pre-DRG and post-DRG enhanced group at one week and 4 weeks after TFESI. Limitations: Retrospective chart review with a small sample size. Conclusion: The improvement of NRS and ODI in the enhanced group was significantly greater than those of the non-enhanced group after TFESI. Radicular pain and functional impairment in the presence of gadolinium enhancing spinal neural structures and lumbar disc herniation may be more responsive to TFESI than patients without enhancing neural structures.