Intraoperative Neurophysiological Monitoring During Continuous Radiofrequency Treatment of Morton’s Neuroma: Complete Ablation

Background and Objectives: Morton’s neuroma is a compressive neuropathy of the common plantar digital nerve that most frequently affects the third intermetatarsal space. Continuous radiofrequency (RF) ablation has reported success rates of approximately 80–85%; however, recent histological evidence suggests that RF does not consistently achieve complete neural ablation. This study aimed to evaluate the effectiveness of intraoperative neurophysiological monitoring of sensory nerve action potentials (SNAPs) to optimize the outcomes of continuous RF ablation in the treatment of Morton’s neuroma. Materials and Methods: This prospective case series included 22 patients (30 neuromas) treated with ultrasound-guided continuous RF ablation combined with intraoperative neurophysiological monitoring. SNAPs were recorded before, during, and after each RF application until complete abolition of sensory nerve conduction was confirmed. Clinical outcomes were assessed using the Visual Analog Scale (VAS), the Foot Function Index (FFI), and the Giannini Interdigital Neuroma Clinical Evaluation Score at 3, 6, and 12 months postoperatively. Results: At the 12-month follow-up, satisfactory outcomes (Giannini score ≥60) were achieved in 86.7% of neuromas (26/30). The mean VAS pain score decreased from 8.67 preoperatively to 1.67 at 12 months. Among the seven neuromas with previous unsuccessful RF treatment, all achieved satisfactory outcomes following the monitored procedure. The four cases with poor outcomes were predominantly associated with a positive anesthetic suppression test, suggesting concomitant mechanical metatarsalgia rather than treatment failure. After excluding cases with likely diagnostic misclassification, the adjusted success rate increased to 96.3%. Conclusions: Intraoperative neurophysiological monitoring enables real-time confirmation of complete sensory nerve ablation during continuous RF treatment. Its main potential value appears to lie in patients with previous unsuccessful conventional RF, all of whom achieved satisfactory outcomes in this series. Persistent postoperative symptoms appeared to be more closely related to concomitant forefoot pathology than to technical limitations of the RF procedure.