753 Clinical Results of Pulsed Radiofrequency Lesioning on Dorsal Root Ganglion in Patients with Chronic Low Back and Leg Pain

INTRODUCTION: Pulsed radiofrequency (RF) was recently described as an alternative technique to conventional, continuous RF lesioning. It allows for application of RF current at 42°C that is not harmful to the tissue. The present study was undertaken to investigate the effect of pulsed RF treatment on dorsal root ganglion (DRG) for chronic segmental pain radiating to the legs. METHODS: There were total of 50 patients with persistent low back pain and leg pain of radicular pattern, without surgery, for more than 6 months. Six of them had pain that had neuropathic components. Average age was 49 years, and average Visual Analog Scale score was 8.4. After diagnostic DRG block, a maximum of 2 DRGs were treated. With a single anteroposterior view under C-arm guidance, a transforaminal approach was used for target selection. After confirmation with contrast dye, impedance and sensory and motor threshold were checked for correct placement of electrodes. The pulsed RF treatment consisted of a 20-ms RF pulse delivered at a rate of 2 Hz for 240 seconds to produce tissue heated to 42°C. Minimal follow-up period was 6 months. RESULTS: All patients tolerated the procedures well. Satisfactory results were defined as 50% reduction of original pain. Thirty-eight cases (76%) were successful at 1 month. However, this was decreased to 32 (64%) at 6 months. Overall patient satisfaction was noted in 40 cases (80%). There were no complications or side effects from the procedures except in two patients with transient soreness. CONCLUSION: Treatment with pulsed RF provided an improvement of chronic low back pain with radiating leg pain of degrees similar to those after conventional continuous RF with a heat of 60 to 67°C without complications. Thus, it would be a useful treatment modality in these clinical settings and may open new horizons for various clinical settings, including neuropathic pain.