The Effect of Bipolar Pulsed Radiofrequency Treatment on Chronic Lumbosacral Radicular Pain Refractory to Monopolar Pulsed Radiofrequency Treatment

BACKGROUND: Patients with lumbosacral radicular pain may complain of persisting pain after monopolar pulsed radiofrequency (PRF) treatment. OBJECTIVE: We evaluated the effect of bipolar PRF stimulation of the dorsal root ganglion (DRG) in patients with chronic lumbosacral radicular pain who were unresponsive to both monopolar PRF stimulation of the DRG and transforaminal epidural steroid injection (TFESI). STUDY DESIGN: This is a prospective observational study. SETTING: The outpatient clinic of a single academic medical center in Korea. METHODS: We retrospectively reviewed data from 102 patients who had received monopolar PRF to the DRG for management of lumbosacral radiculopathy. Of these, 32 patients had persistent radicular pain that was scored at least 5 on a numeric rating scale (NRS). Twenty-three of them were included in this study and underwent bipolar PRF of the DRG. The outcomes after the procedure were evaluated using the NRS for radicular pain before treatment and 1, 2, and 3 months after treatment. Successful pain relief was defined as >/= 50% reduction in the NRS score compared with the score prior to treatment. Furthermore, at 3 months after treatment, patient satisfaction levels were examined. Patients reporting very good (score = 7) or good results (score = 6) were considered to be satisfied with the procedure. RESULTS: The NRS scores changed significantly over time. At 1, 2, and 3 months after bipolar PRF, the NRS scores were significantly reduced compared with the scores before the treatment. Twelve (52.2%) of the 23 patients reported successful pain relief and were satisfied with treatment results 3 months after bipolar PRF. No serious adverse effects were recorded. LIMITATIONS: A small number of patients were recruited and we did not perform long-term follow-up. CONCLUSION: We believe the use of bipolar PRF of the DRG can be an effective and safe interventional technique for chronic refractory lumbosacral radiculopathy. It appears to be a potential option that can be tried before proceeding to spinal surgery. KEY WORDS: Bipolar, pulsed radiofrequency, lumbosacral radicular pain, chronic pain, dorsal root ganglion, spinal stenosis, herniated disc.