Long-term Efficacy of Genicular Nerve Ablation for Chronic Osteoarthritic Knee Pain: A Prospective Observational Longitudinal Study

Abstract

Objective: When patients with chronic osteoarthritis (OA) knee pain do not respond to conservative treatment and are not suitable for knee arthroplasty, radiofrequency ablation (RFA) of the genicular nerve is probably an alternative treatment. This study aimed to evaluate the efficacy and safety of genicular nerve ablation in severe osteoarthritic knee pain patients. Materials and Methods: Patients with severe chronic OA knee pain were recruited and performed a genicular nerve block (GNB). The patients’ demographic data, numerical rating scale (NRS) at rest and on movement, Thai Oxford knee score (Thai OKS), Thai knee injury and osteoarthritis outcome score physical function short form (Thai KOOS-PS), timed up and go test, brief pain inventory, fall evaluation, and EuroQol 5D-5L were recorded. For the positive block patients (≥50% pain relief for 24 hours), genicular nerve RFA was performed under fluoroscopic or ultrasound guidance. All patients were followed up at the 1st, 3rd, 6th, 9th and 12th months. Results: 21 patients were included in the study, but only 17 were completely followed up for 12 months. At the 12th month, genicular nerve RFA reduced the mean NRS on movement from 7.9±1.6 to 4.0±2.6 (p=0.005), improved knee function (Thai OKS from 18.8±5.3 to 28.5±10.1; p=0.006), but did not significantly improve quality of life (EuroQol-5D-5L from 0.43±0.20 to 0.69±0.33; p=0.130). No adverse events were observed. Conclusion: Genicular nerve radiofrequency ablation in severe chronic OA knee patients demonstrated significant pain relief and functional improvement for up to 12 months without serious adverse events.