Morton's neuroma: a microscopic evaluation.

Microscopic evaluation of the interdigital neuroma is described in 24 nerves which were evaluated at six cross-section areas for size of the nerve and width of the perineural along with the fascicle diameter and the size and number of blood vessels inside each fascicle. A relationship was noted between the level of the distal edge of the intermetatarsal ligament. Cross-section that was taken at that area showed changes distally in nerve diameter, fascicle number and size, blood vessel number and size, and perineural width. These changes are consistent with the interdigital neuroma as an entrapment condition.