Localized Interdigital Neuritis / Morton Neuroma

Definition

Non-neoplastic, degenerative process, usually affecting plantar and digital nerves characterized by axon and myelin loss accompanied by fibrosis

Painful lesion of the foot, nearly always of the third metatarsal interspace
- May rarely involve digital nerves
Marked fibrosis of perivascular, epineurial, and perineurial tissue
- Hyalinization and thrombosis of arterial vessels is common
Depletion of axons within the peripheral nerve
Elastic fibers increased at the periphery of the lesion
Primarily affects women (80%)

Jason Karamchandani MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342