radial nerve

Origin

• posterior cord of brachial plexus (C5-C8)
• carries fibers from all roots of the plexus

Afferents

• skin overlying innervated muscles (efferents)
  • sensory innervation to dorsum of hand

Efferents

• muscles involving supination of forearm
  • triceps, brachioradialis
• extensors of the elbow, wrist, thumbs & fingers

Course

• curves around the posterior surface of the humerus & passes inferiorly to the cubital fossa where it divides into its two terminal branches

Branches

• superficial cutaneous branch
• deep motor branch

Pathology

Injury: radial nerve palsy

• axilla & fractures of the middle 1/3 of humerus
• results in "wrist drop"
• sensory loss to dorsum of hand
• resisted weakness in elbow & thumb extension

More general terms

• peripheral nerve

Additional terms

• radial nerve palsy; radial nerve entrapment; wrist drop; Saturday night palsy