A randomized, double-blind, prospective study comparing the efficacy of continuous versus pulsed radiofrequency in the treatment of lumbar facet syndrome

Study Objectives: To compare the efficacy of continuous radiofrequency (CRF) thermocoagulation with pulsed radiofrequency (PRF) in the treatment of lumbar facet syndrome. Design: Prospective, randomized, double-blinded study. Setting: Ambulatory pain clinic at a level-I traurna center and teaching institution. Patients: 50 ASA physical status I, II, and III patients, at least 18 years of age, scheduled to undergo CRF or PRF for lumbar back pain. Interventions: Target facet joints were identified with oblique radiographic views. Continuous radiofrequency thermocoagulation was delivered at 80 degrees C for 75 seconds, while PRF was delivered at 42 degrees C with a pulse duration of 20 ms and pulse rate of two Hz for 120 seconds. Measurements: Visual analog scale (VAS) pain assessment and Oswestry Low Back Pain and Disability Questionnaire (OSW) were administered at baseline and then at three months. Comparisons between groups and within groups were made of the relative percentage improvement in VAS and OSW scores. Main Results: No significant differences in the relative percentage improvement were noted between groups in either VAS (P=0.46) orOSW scores (P=0.35). Within the PRF group, comparisons of the relative change over time for both VAS (P=0.21) and OSW scores (P=0.61)were notsignificant. However, within the CRF group, VAS (P = 0.02) and OSW scores (P = 0.03) showed significant improvement. Conclusions: Although there was no significant difference between CRF and PRF therapy in long-term outcome in the treatment of lumbar facet syndrome, there was a greater improvement overtime noted within the CRF group. (C) 2008 Elsevier Inc. All rights reserved.