Poster 134: Lumbar Zygapophyseal Joint Radiofrequency Denervation: A Long-Term Clinical Outcome Study

Abstract

Objective: Zygapophysial joint pain has long been suggested to be 1 of the sources of low back pain. Radiofrequency denervation of the medial branches of the dorsal rami to treat z-joint pain is an outpatient minimally invasive treatment option. There have been many short-term studies to determine the outcome of the procedure, but few long-term studies have been conducted. Our goal was to clarify whether radiofrequency denervation has any long-term clinical benefit. Design: Retrospective cohort study. Setting: Academic physiatric outpatient practice. Participants: A total of 42 patients (17 men and 25 women), with an average follow-up of 3.5 years, with clinical signs of zygapophysial joint involvement who have failed conservative treatment (preprocedure symptom duration mean 6.03y; range, 5mo–48y), and had a favorable response to a diagnostic medial branch block or zygapophysial joint injection. Interventions: The identified subjects underwent radiofrequency denervation at the Hospital for Special Surgery physiatry department from 1998 to 2006. Patients' records were reviewed and a questionnaire was provided, completed by phone follow-up or mailed by the patient. Main Outcome Measures: Numerical Rating Scale-11, North American Spine Society 4-point satisfaction index, and a modified Roland-Morris Disability Questionnaire to assess improvement in pain and function. Results: 52% of patients reported a successful outcome with improved function at a minimum follow-up period of 2 years (mean 3.5y, range, 2–8.8y). Patients in the failure group were more likely to be older and have moderate to severe neuroforaminal stenosis (77.8%) compared with patients in the success group (24.2%). Conclusions: Radiofrequency denervation in selected patients with chronic zygapophysial joint mediated low back pain provides long-term reduction in pain and improved function with minimum morbidity.