Table 1.

Classification of nerve injuries by Seddon and Sunderland

Sunderland	Seddon	Description	Examples
I	Neuropraxia	Localized damage to myelin	Relatively mild injury often involving compression of the nerve at a bony interface or indolent growth of a tumor
II	Axonotmesis	Loss of axon continuity with damage to myelin	Motor vehicle accidents, falls, and physical assault are all common inciting events for grade II–IV injury
III		Injury to myelin, axon, and endoneurium
IV		Injury to myelin, axon, endoneurium, and perineurium
V	Neurotmesis	Complete transection of all components including epineurium	Laceration from sharp objects including knives, glass, surgical instruments, or animal bites