Ultrasound-guided radiofrequency ablation in the management of interdigital (Morton's) neuroma

Abstract

Objective: To identify the benefits of ultrasound-guided radiofrequency ablation of Morton's neuroma as an alternative to surgical excision.

Materials and methods: We studied a consecutive cohort of surgical candidates for Morton's neurectomy who we referred, instead, for radiofrequency ablation (RFA). Under local anaesthetic, RFA was performed under ultrasound guidance, by a single radiologist. This out-patient procedure was repeated after 4 weeks if necessary. We followed patients for a minimum of 6 months to assess their change in visual analogue pain scores (VAS), symptom improvement, complications and progression to surgical excision.

Results: Thirty feet in 25 patients were studied. There were 4 men and 21 women with an average age of 55 years (range 33-73 years). All had tried previous methods of conservative management. Forty percent presented with 2nd space neuromas and 60% with 3rd space ones. The average number of treatment sessions was 1.6 (range 1-3, mode 1). Prior to treatment, all patients had pain on activity (VAS average: 6.0, range 3-9). Post-treatment there was a statistically significant reduction in pain scores (post-RFA VAS average: 1.7, range 0-8, p < 0.001). The average overall symptom improvement was 76%. There was one minor complication of temporary nerve irritation. Three neuromas (10%) have progressed to surgical excision; 1 patient has ongoing, unchanged pain with no obvious cause. At 6 months, 26 out of 30 feet had a satisfactory outcome.

Conclusion: Ultrasound-guided RFA has successfully alleviated patients' symptoms of Morton's neuroma in >85% of cases. Only 10% have proceeded to surgical excision in the short term.