Effect of Patient Characteristics on Reported Outcomes Over 12 Months Following Lumbar Radiofrequency Ablation: A Retrospective Review of 500 Patients

Abstract

Background: Low back pain is the leading cause of years lost to disability worldwide. Approximately 15% to 45% of chronic low back pain is due to facet joint arthropathy. Currently, no large-scale retrospective studies have investigated long-term clinical predictors of success in individuals receiving radiofrequency ablation (RFA) of the medial branches for facet joint arthropathy.

Objective: To determine the clinical factors associated with success and failure of RFA of lumbar facet joints at 1-year follow-up.

Methods: Clinical data were gathered from 500 consecutive patients with an International Classification of Diseases (ICD)-10 diagnosis of lumbar spondylosis. VAS pain scores for patients undergoing lumbar medial branch RFA procedures were recorded at multiple time points, up to the 1-year follow-up visit. A responder was defined as having ≥30% improvement in VAS score from the pre-procedural VAS score. For our primary analysis, regression analysis was conducted to identify associations between responder status and patient characteristics, including age, gender, body mass index (BMI), hormone use, opiate dose, and smoking history at multiple time points, up to the 1-year follow-up visit.

Results: A total of 500 patients were included in the study. At the 1-year post-RFA follow-up visit, responder status was associated with a lower rate of prior opioid use (43.22% vs. 55.76%, odds ratio 0.60 [95% confidence interval (CI) 0.40 to 0.92], P = 0.018), lower pre-procedural opioid consumption in oral morphine equivalents (10.16 ± 16.02 vs. 14.67 ± 20.65, β -4.50 [95% CI -8.57 to -0.44], P = 0.030), and a higher pre-VAS pain score (6.36 ± 2.17 vs. 5.85 ± 2.17, β 0.50 [95% CI 0.06 to 0.95], P = 0.028). There were no significant associations between responder status and age, gender, BMI, hormone use, and smoking history at the 1-year follow-up visit.

Conclusions: Our results suggest that patients prescribed opioids, particularly at higher dosages, may find less pain relief 1 year following RFA for facetogenic pain. Additionally, patients with higher pre-procedural VAS pain scores may be more likely to have a positive response at 1 year.

Keywords: chronic pain; low back pain; lumbar spondylosis; radiofrequency ablation.