Short-term clinical and imaging outcomes after ultrasound-guided cooled radiofrequency ablation for advanced knee osteoarthritis: a retrospective cohort study

Objective To evaluate short-term clinical and imaging outcomes after ultrasound-guided cooled radiofrequency ablation (CRFA) in patients predominantly with advanced knee osteoarthritis (KOA).Methods This retrospective cohort analysis included prospectively recorded data from 31 patients (35 knees; age, 73.6 ± 8.8 years; Kellgren-Lawrence [KL] grade 3 or 4 in 91%). Outcomes at baseline and 3 months included visual analog scale (VAS) pain, Knee Injury and Osteoarthritis Outcome Score (KOOS), KL grade, mechanical axis percentage, and MRI Osteoarthritis Knee Score assessments of bone marrow lesions (BMLs), Hoffa-synovitis, and effusion-synovitis. Sensitivity analysis retained the first-treated knee in bilateral cases.Results VAS changes were −9.3 for rest pain, −24.0 for walking pain, and −15.0 for night pain (all p < 0.05). Walking VAS decreased by at least 30% in 65.7% and by at least 50% in 42.9% of knees. Four KOOS subscales improved, including KOOS Pain by 12.8 points (p < 0.001). No significant group-level changes were observed in KL grade, alignment, or BML scores. Hoffa-synovitis and effusion-synovitis scores decreased. No serious procedure-related adverse events were documented.Conclusion CRFA was associated with improved pain and function at 3 months without group-level worsening in KL grade, alignment, or BML scores. Longer-term controlled studies are required.