02 Wallerian Degeneration

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Peripheral

• trauma
• arms/legs
• mild damage: neurapraxia

Neurapraxia

• Continuity: rest of nerve not severed

Neurotmesis

• entire nerve damaged, including epineurium

Axonotmesis

• nerve distal and proximal to lesion react differently

• axonal regrowth happens if schwann cell is intact

CNS

Injury

• ischemia

• red neurons = ischemia

• cyst walled off by astrocytes

UMN vs LMN

• 3+ reflex

Bulbar

• face and neck
• bulbar palsy or symptoms

Links to this note

• step 1 Neurology
  • 02 Wallerian Degeneration

• bulbar palsy: LMN palsy of bulbar