Morton’s neuroma is an entrapment neuropathy resulting in localised enlargement of one of the interdigital nerves. The third web space (between the third and fourth toes) is most commonly involved. The condition usually presents with plantar foot pain and there is tenderness in the involved web space. Although a mass is seen on imaging, frequently no mass is palpable clinically. Surgical treatment involves excision of the neuroma or swelling.
In the example below a 4mm neuroma is seen in the third web space with a surrounding cuff of reactive soft tissue inflammatory oedema. The toes are numbered 1 (great toe) to 5 (little toe).