Radial nerve
Important landmarks
- exits axilla via triangular interval - between inferior border of teres major, long head of triceps brachii, humeral shaft
- accompanied by profunda brachii
- passes around posterior surface of the middle of the humerus in the radial groove
- anterior to lateral epicondyle
branches
- posterior cutaneous branch
- superficial branch
- only branch that enters the hand
- cutaneous supply to dorsolateral hand + dorsal aspect of lateral 3.5 digits
- deep branch (extensor carpi radialis brevis) → continues as:
- posterior interosseous (after emerging from 2 heads of supinator)
- deep layer of posterior compartment of forearm = finger extension including thumb
Territory
Extensor compartment of arm - all posterior compartment of forearm and arm
- Muscles acting at elbow joint
- muscles of the posterior forearm
Cutaneous: - lower lateral arm
- posterior arm + forearm
- dorsum of lateral hand and 3.5 fingers
Injury
Mechanism
Anterior shoulder dislocation
Humeral shaft fracture
clinical presentation
wrist drop