Genicular nerve radiofrequency ablation for the treatment of chronic knee joint pain: a real-world cohort study with evaluation of prognostic factors

Abstract

Background: Genicular nerve radiofrequency ablation (GNRFA) is an effective treatment for chronic knee pain. However, there has been minimal investigation of real-world, long-term outcomes and factors that predict treatment success after GNRFA. Objectives: To evaluate the effectiveness of GNRFA for chronic knee pain in a real-world population and identify predictive factors. Methods: Consecutive patients who underwent GNRFA at a tertiary academic center were identified. Demographic, clinical, and procedural characteristics were collected from the medical record. Outcome data were numeric rating scale (NRS) pain reduction and Patient Global Impression of Change (PGIC). Data were collected by standardized telephone survey. Predictors of success were evaluated with logistic and Poisson regression analyses. Results: Of the 226 total patients identified, 134 (65.6 6 12.7; 59.7% female) were successfully contacted and analyzed, with a mean follow-up time of 23.3 6 11.0 months. Of those, 47.8% (n ¼ 64; 95% CI: 39.5%–56.2%) and 61.2% (n ¼ 82; 95% CI: 52.7%–69.0%) reported ≥50% NRS score reduction and ≥2-point NRS score reduction, respectively, and 59.0% (n ¼ 79; 95% CI: 50.5%–66.9%) reported “much improved” on the PGIC questionnaire. Factors associated with a greater likelihood of treatment success (P < .05) were higher Kellgren–Lawrence osteoarthritis grade (2–4 vs 0–1); no baseline opioid, antidepressant, or anxiolytic medication use; and >3 nerves targeted. Conclusion: In this real-world cohort, approximately half of the participants experienced clinically meaningful improvements in knee pain after GNRFA at an average follow-up time of nearly 2 years. Factors associated with higher likelihood of treatment success were more advanced osteoarthritis (Kellgren–Lawrence Grade 2–4); no opioid, antidepressant, or anxiolytic medication use; and >3 nerves targeted.