Axillary Nerve

• Roots
  • C5 and C6.
• Motor Functions
  • Teres minor
  • Deltoid muscles
• Origin
   - Arises from the posterior cord of the brachial plexus
• Course
  • Exits the axilla through the Quadrangular space, bounded by:
    • Superior: teres minor
    • Inferior: teres major
    • Medial: long head of triceps
    • Lateral: surgical neck of the humerus
  • Winds around the surgical neck of the humerus deep to the deltoid
  • Divides into anterior and posterior branches
• Sensory Functions
  • Gives off the superior lateral cutaneous nerve of arm