Workup and Management of Persistent Neuralgia following Nerve Block

Table 1

Seddon-Sunderland Classification of Nerve Injuries [1].

Degree of injury	Type of injury	Characteristics
1	Neuropraxia	Temporary conduction block with preserved axonal continuity.; Nerve conducts normally above and below injury, but not across it.
2	Axonotmesis	Continuity of endoneurial sheath, with Wallerian degeneration distal to the lesion. Regenerating axon will restore innervation to original target.
3	Neurotmesis with intact perineurium	Concealed intrafascicular lesion with preserved continuity of fasciculi, but discontinuity of nerve axons.
4	Neurotmesis with intact epineurium	Destruction of fascicular structure with nerve trunk continuity, a strand of disorganized tissue. Requires excision and nerve repair.
5	Complete neurotmesis	Loss of continuity of complete nerve including epineurium, perineurium, endoneurium, and axons.