Traumatic and compressive lesions of peripheral nerves

Injuries to peripheral nerves range from acute and chronic compression, to entrapment and traumatic transection. Clinically, traumatic lesions present with loss of sensation and muscle power; electrophysiology is used to localize lesions and to determine their nature and extent. Pathology of traumatic lesions ranges from myelin displacement and demyelination in compressive lesions to complete transection of nerves associated with penetrating injuries and fractures. Entrapment of peripheral nerves occurs in bony or muscle and ligamentous tunnels, particularly in older age groups with damage to nerves from stretching, restriction of movement and deprivation of blood supply. Focal lesions that result from trauma to peripheral nerves described here include traumatic neuromas, Morton's neuroma, reactive perineurial hyperplasia and focal hypertrophic neuropathy. Copyright © 2014 International Society of Neuropathology.