CAUSES OF NEUROPRAXIA, AXONOTMESIS AND NEUROTMESIS

Question 1

Mild compression injury (e.g. Saturday night palsy and other entrapment neuropathies) leading to mechanical deformation of the nerve and/or ischemia.

Answer 1

NEUROPRAXIA

Question 2

Often transient resulting in short-term disruption of conduction

Answer 2

NEUROPRAXIA

Question 3

May involve mild damage to myelin sheath resulting in numbness, paresis from slower conduction (e.g. mild or early CTS)

Answer 3

NEUROPRAXIA

Question 4

Can be a result of a more severe impact or a stronger/more sustained compressive situation; can be caused by neuritis, infections (e.g. Lyme disease, toxins, GBS, diabetes related ischemia.

Answer 4

AXONOTMESIS

Question 5

Can also occur when the nerve is stretched (without damage to the epineurium).

Answer 5

AXONOTMESIS

Question 6

Severance injuries (knife blade injuries/cuts, displacing fractures) and ruptures/traction injuries; also, amputations, crush injuries – industrial accidents, MVAs that do not leave viable distal segments

Answer 6

NEUROTMESIS

Question 7

Includes damage to endoneurium, perineurium and in the most severe cases the epineurium

Answer 7

NEUROTMESIS