Optimal Temperature for Radiofrequency Ablation of Lumbar Medial Branches for Treatment of Facet-Mediated Back Pain

Background: Radiofrequency ablation (RFA) of the medial branch nerves that innervate the facet joints is a well-established treatment modality; however, studies to determine the optimal radiofrequency ablation temperature are lacking. A wide range (70 to 90 degrees C) has been used. This study aimed to compare outcomes with two set temperatures for the lumbar facet medial branch ablation, 90 and 80 degrees C. Methods: This retrospective study compared the degree of patient self-reported functional improvement relief, postoperative opioid dose changes, as well as duration among lumbar facet medial branch (RFA) patients who had the procedures performed at 80 or 90 degrees C. Results: Patients who underwent the procedure at 90 degrees C had 3.1 (95% CI 1.7, 6.5) times the odds (P = 0.0004) of reporting functional improvement of at least 50% when compared to those who underwent neurotomy at 80 degrees C. For self-reported functional improvement greater or equal to 75%, the results were sustained with an odds ratio of 2.8 (95% CI 1.2, 5.7) favoring those with 90 degrees C temperature neurotomy (P = 0.002). Conclusion: There seems to be significant functional improvement associated with temp of 90 degrees C compared to 80 degrees C, with no added risk of complications. Randomized controlled studies are warranted.