Painful neuroma: changes produced in peripheral nerve after fascicle ligation.

Sixteen months after resection of a painful neuroma and fascicle ligation of the proximal nerve segments, the fascicle ligated neural tissue was examined by light and electron microscopy. No significant neuroma formation was found in the fascicle-ligated regions. The distal portion consisted mainly of connective tissue fibroblasts with an absence of neural elements. Maintaining the perineurium intact by fascicle ligation seems to alter significantly axonal regeneration in humans, as is indicated by minimal neuroma formation. Similar findings after fascicle ligation in animals have also been reported. This lack of neuroma formation after resection of a painful neuroma and fascicle ligation may play a significant role in relieving pain in patients with painful neuromas.