Effect of Radiofrequency on Dorsal Root Ganglion Versus Transforaminal Steroids Injection on Tumor Necrosis Factor-Alpha Level in Lumbar Radicular Pain.

BACKGROUND

The mechanism of pain control with pulsed radiofrequency (PRF) is unclear.

OBJECTIVES

We aimed to compare the efficacy of combined PRF on dorsal root ganglion (DRG) with transforaminal epidural steroid injection (TFESI) vs TFESI-alone on pain improvement and serum tumor necrosis factor-alpha (TNF-a) level in lumbar disc-related radicular pain.

STUDY

DESIGN

Prospective, randomized, controlled trial.

SETTING

Neurology and Pain Management clinics.

METHODS

A total of 80 patients with lumbar disc prolapse were divided into 2 groups: combined PRF on DRG with TFESI group and TFESI-alone group. The Numeric Rating Scale (NRS-11), Oswestry Disability Index (ODI), and Functional Rating Index (FRI) before intervention and at 2 weeks, 1 month, and 3 months after the intervention were observed. Serum TNF-a level was assessed pre- and post-intervention at 3 months.

RESULTS

The scores of NRS-11, ODI, and FRI showed a significant improvement at 2 weeks, 1 month, and 3 months following intervention in both combined PRF & TFESI group and TFESI-alone group (P < 0.001 in all comparisons), with no significant difference between the 2 groups. Serum TNF-a levels showed a statistically significant reduction, 3 months following intervention in the combined PRF & TFESI group (P < 0.001), but not in the TFESI-alone group (P = 0.297) (P between groups < 0.001).

LIMITATIONS: The main limitation of this study is that TNF-a level was not assessed earlier to see how long the steroids might reduce TNF-a. On the other hand, further study with extended follow-up periods is needed to confirm the long-term lowering effect of TNF-a provided by PRF.

CONCLUSIONS

Combined PRF on DRG with TFESI showed similar outcomes to TFESI-alone in relieving pain in patients with lumbar disc prolapse. However, PRF on DRG caused a significant decrease in TNF-a serum levels at 3 months.