Selective Thermal Radiofrequency Ablation of the Deep Peroneal Articular Branches for Refractory Ankle Osteoarthritis: A Case Report

Patients with ankle osteoarthritis who do not respond to conservative treatment remain a therapeutic challenge.This report describes selective thermal radiofrequency ablation of the deep peroneal articular branches in a patient with refractory ankle osteoarthritis and predominantly anterior pain.A 72-year-old man presented with refractory bilateral mechanical ankle pain, worse on the right side, centered on the anterior joint line, and rated 9/10 on the numeric pain rating scale (NPRS).Intra-articular treatment provided partial relief, whereas repeated pulsed radiofrequency of the deep peroneal nerve achieved greater but time-limited relief.A diagnostic deep peroneal nerve block produced complete rightsided relief during walking and weight-bearing dorsiflexion, without motor deficit.Thermal radiofrequency of the right deep peroneal articular branches was then performed under combined ultrasound and fluoroscopic guidance.At 12 months, pain had decreased from 7/10 to 3/10, with no motor deficit.The remaining pain was localized over a prominent anterior osteophyte and occurred mainly during prolonged standing and activities requiring increased ankle dorsiflexion, particularly uphill walking.In refractory ankle osteoarthritis with predominantly anterior pain, correlating the pain distribution with the articular anatomy allowed selection of a single neural target.A positive diagnostic nerve block supported the analgesic target, and motor stimulation before ablation excluded motor fiber recruitment.In this patient, thermal radiofrequency near a mixed nerve provided prolonged analgesia without motor deficit.Residual pain after denervation should be reassessed, as it may reveal a mechanical component requiring a different therapeutic approach.