Seddon's and Sunderland's Classification of Nerve Injury

Classifications:

• Neuropraxia (Sunderland 1°)

• Axonotmesis (Sunderland 2° and 3°)

• Neurotmesis (Sunderland 3°, 4°, and 5°)

• Segmental demyelination

• Action potential slowed or blocked at point of demyelination; normal above and below point of compression

• The result of mild ischemia from nerve compression or traction

Neuropraxia (Sunderland 1°)

Signs and symptoms of Neuropraxia (Sunderland 1°):

• Pain

• No or minimal muscle wasting 

• Muscle weakness

• Numbness

• Proprioception affected

Recovery time for Neuropraxia (Sunderland 1°):

Minutes to days

• Loss of axonal continuity but connective tissue coverings remain intact

• Wallerian degeneration distal to lesion

• The result of prolonged compression or stretch causing infarction and necrosis

Axonotmesis (Sunderland 2° and 3°)

Signs and symptoms of Axonotmesis (Sunderland 2° and 3°):

• Pain

• Muscle wasting evident

• Complete motor, sensory and sympathetic functions lost

• Sensation is restored before motor function

Recovery time for Axonotmesis (Sunderland 2° and 3°):

Months (axon regenerates at rate of 1 inch/month, or 1 mm/day)

• Complete severance of nerve fiber with disruption of connective tissue coverings

• Wallerian degeneration distal to lesion

• The result of gunshot or stab wounds, avulsion, rupture

Neurotmesis (Sunderland 3°, 4°, and 5°)

Signs and symptoms of Neurotmesis (Sunderland 3°, 4°, and 5°):

• No pain (anesthesia)

• Muscle wasting

• Complete motor, sensory and sympathetic functions lost

Recovery time for Neurotmesis (Sunderland 3°, 4°, and 5°):

Months and only with surgery