Morton neuroma: sonographic evaluation.

One hundred consecutive patients with symptoms suggestive of Morton neuroma were examined with sonography, and 134 intermetatarsal masses were demonstrated. Forty-five patients underwent surgical exploration, which revealed Morton neuromas. The typical sonographic appearance is that of an ovoid, hypoechoic mass oriented parallel to the long axis of the metatarsals. Most masses were between the second and third or third and fourth metatarsals and seemed to produce symptoms when reaching a diameter of 5 mm.