Comparison between bipolar pulsed radiofrequency and monopolar pulsed radiofrequency in chronic lumbosacral radicular pain: A randomized controlled trial

Abstract

Background: Chronic lumbosacral radicular pain is a challenging medical problem with respect to therapeutic management. Many patients with lumbosacral radicular pain complain of persistent leg pain after transforaminal epidural steroid injection. Nowadays, pulsed radiofrequency (PRF) stimulation on the dorsal root ganglion (DRG) is widely used for controlling lumbosacral radicular pain.

Methods: We evaluated the effect of bipolar PRF on the DRG for the management of lumbosacral radicular pain. In addition, we compared the effect of bipolar PRF to monopolar PRF. Fifty patients with chronic lumbosacral radicular pain were included in the study and randomly assigned to 1 of 2 groups, the bipolar or monopolar PRF group (n = 25 per group). Pain intensity was evaluated using a numeric rating scale (NRS) at pretreatment, and 1, 2, and 3 months after treatment.

Results: When compared to the pretreatment NRS scores, patients in both groups showed a significant decrease in NRS scores at 1, 2, and 3 months after treatment. Reductions in the NRS scores over time were significantly larger in the bipolar PRF group. Three months after treatment, 19 patients (76.0%) in the bipolar PRF group and 12 patients (48.0%) in the monopolar PRF group reported successful pain relief (pain relief of ≥50%).

Conclusion: The use of bipolar PRF on the DRG can be an effective and safe interventional technique for chronic refractory lumbosacral radiculopathy, particularly in patients whose pain are refractory to epidural steroid injection or monopolar PRF stimulation.

Figure 1

Fluoroscopy-guided bipolar pulsed radiofrequency (left) and monopolar pulsed radiofrequency (right) of the left L5 dorsal root ganglion.

Figure 2

Changes in NRS. When compared to pretreatment NRS scores, both groups showed a significant decrease in scores at 1, 2, and 3 months after treatment. However, 1, 2, and 3 months after the procedures, the NRS score was significantly lower in the bipolar pulsed radiofrequency (PRF) group than in the monopolar PRF group. ^∗P < 0.05: intragroup comparison between 1, 2, and 3 months posttreatment, and pretreatment (repeated measure 1 factor analysis). ^†P < 0.05: intergroup comparison in each time point (repeated measure 2 factor analysis). NRS = numeric rating scale, PRF = pulsed radiofrequency.