Score: Seddon-Sunderland classification
Use: Nerve injury
Grade 1: Neuropraxia
Conduction disruption with intact axon and preserved supportive structures.
Prognosis: normally full recovery in days-weeks without surgical intervention
Grade 2: Axonotmesis
Disrupted axon with intact endoneurium; Wallerian degeneration takes place after 1-2 weeks
Prognosis: variable recovery, worse prognosis for proximal injuries and injuries who do not successfully re-implant in the muscle within 18 months
Grade 3: Neurotmesis with preservation of perineurium
Neurotmesis refers to disruption of supporting structures
Endoneurium is disrupted
Prognosis: 60-80% recovery
Grade 4: Neurotmesis with preservation of epineurium
Prognosis: nerve grafting is required
Grade 5: Neurotmesis with complete transection of nerve trunk
Prognosis: bypass / jump grafting is requiredReference
http://wiki.cns.org/wiki/index.php/Injury,_Classification