Bipolar RFA Versus Phenol Neurolysis for Knee Osteoarthritis Pain

This prospective observational comparative study evaluates the analgesic efficacy and safety of ultrasound-guided bipolar radiofrequency ablation (BPRFA) versus phenol chemical neurolysis (PCN) of the genicular nerves in patients with chronic knee osteoarthritis (gonarthrosis) refractory to conservative treatment. Patients with moderate-to-severe chronic knee pain who demonstrate significant pain relief following diagnostic genicular nerve block undergo either BPRFA or PCN targeting the superior medial, superior lateral, and inferior medial genicular nerves under ultrasound guidance. Pain intensity and functional outcomes are assessed using the Numeric Rating Scale (NRS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at baseline and during follow-up evaluations at 4, 12, and 24 weeks after treatment. The study aims to compare pain reduction, functional improvement, responder rates, and procedure-related adverse events between the two treatment modalities.

Inclusion Criteria: * Adults aged 18 to 75 years * Unilateral moderate-to-severe knee pain due to gonarthrosis * Numeric Rating Scale (NRS) score ≥6 * Knee pain lasting longer than 6 months * Radiological diagnosis of knee osteoarthritis, Kellgren-Lawrence grade 2-4 * Failure of conservative treatments, including analgesic medications, physical therapy, or intra-articular injections * At least 50% pain relief after diagnostic genicular nerve block * Ability to provide written informed consent Exclusion Criteria: * Knee pain due to causes other than osteoarthritis, such as fracture, trauma, spinal disorder, or inflammatory arthritis * Previous knee surgery * Knee joint effusion detected on physical examination or ultrasound * Cognitive impairment * Hepatic or renal failure * Severe psychiatric disorder * Local or systemic infection * Coagulopathy * Current use of antiplatelet or anticoagulant therapy * Presence of a pacemaker * Intra-articular injection or interventional knee procedure within the previous 6 months