Patient's assessment of discomfort during ultrasound-guided injection of Morton's neuroma: selecting the optimal approach.

PURPOSE: Assess patient discomfort during two different methods of injection of Morton's neuroma. METHODS: Sixty-eight patients referred for ultrasound-guided injection of Morton's neuroma had punctures performed dorsal or plantar to the interdigital skin crease, with and without preliminary subcutaneous local anesthesia (LA). Patients rated discomfort during skin puncture (SP) and needle advancement (NA) using a visual analog scale. RESULTS: Average pain score was 4.4 ± 2.3 (1 SD) for the plantar approach and 2.9 ± 2.0 for the dorsal approach. This difference was statistically significant during SP (p < 0.01) and NA (p < 0.05). During the plantar approach with LA, mean pain score during SP was 4.4 (± 2.1) and 3.9 (± 2.8) during NA. This plantar approach without LA resulted in a pain score of 4.3 (± 2.6) and 3.8 (± 3.1), respectively. Mean pain scores for patients injected from the dorsal approach with LA during SP were 3.8 (± 2.7) and NA were 2.2 (± 2.0) and without LA were 2.6 (± 1.9) and 3.0 (± 2.1). There was no statistical significance in mean pain score difference during SP and NA, with and without LA for either the plantar (p > 0.05) or the dorsal (p > 0.05) approach. CONCLUSIONS: Injection of Morton's neuroma was better tolerated via a dorsal approach and use of preliminary LA did not confer any benefit.