Radial Nerve
- Radial nerve
- origin and root value
- from brachial plexus ( posterior fibers )
- as a terminal branch of posterior cord
- C5, C6, C7, C8 and T1
- Course
- Arm
- travels behind 3rd part of axillary artery
- runs behind brachial artery
- enters lower triangular space
- to reach radial sulcus of back of humerus
- here it gives muscular branches to triceps brachii
- after emrgence from radial sulcus
- it gives brachialis, brachioradialis and extensor carpi radilis longus
- travels together with profunda brachii artery
- between lateral and medial head of triceps
- until it reaches lateral side of arm
- 5 cm below deltoid tuberosity it pierces
- intermuscular septum to reach anterior compartment of arm
- descends down to cross lateral epicondyle of humerus
- terminates by dividing
- superficial branch
- deep branch
- Cubital fossa
- superficial and deep branch continue in cubital fossa
- Forearm
- superficial ( sensory ) branch
- passes along front of the radial side of forearm
- at first lies
- slightly lateral to radial artery concealed beneath brachioradialis
- in middle third of forearm
- lies behind same muscle
- in lower forearm 7 cm above wrist
- passes beneath tendon of brachioradialis
- divides in to
- medial branch
- communicates
- then divides in to four digital nerves
- first supplies ulnar side of thumb
- second radial side of index finger
- third - adjoining sides of index and middle fingers
- fourth -
- lateral branch
- supplies the radial (lateral) side of thumb
- ball of thumb
- Deep branch ( motor ) or posterior interosseus nerve
- winds to the back of forearm
- around lateral side of radius
- between two planes of fibers of supinator
- prolonged downwards to middle of forearm
- supplies motor muscles in posterior compartment
- extensor compartment
- clinical
- wrist drop due to paralysis to posterior cord
- Radial dislocation
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- wrist drop
-
- Injury
- Injury to the radial nerve at different levels causes different syndromes with varying motor and sensory deficits.
- AT THE AXILLA
- AT MIDARM
- JUST BELOW ELBOW
- WITHIN DISTAL FOREARM
- Motor deficit: None
Discussion