Radial Nerve Course. (branches not discussed)
Posterior wall of axilla.
Triangular Space with profunda brachii
enters Posterior compartment of arm.
runs along Spiral Groove between medial and long heads.
peirces lateral intermuscular septum never less than 7.5 cm above the distal articular surface.
enters Anterior compartment of the arm
Appears between brachialis and brachoradialis to over lateral epicondyle between brachialis medially & BR.
The radial Nerve itself (i.e not the posterior interosseous), innervates the brachioradialis + ECRL (both branches come off in the brachialis-brachioradialis groove.
The radial nerve innervates anconeuous. The radial nerve branch to the medial head of tricepts peirces it to supply anconeus.
Radial nerve innervation - A BET - anconeus, brachioradialis, ECRL, Triceps
Posterior Interosseous Nerve Course. (branches not discussed)
Begins as continuation of radial nerve in flexor compartment of elbow.
Enters supinator at arcdade of Frosch (Thickening between two heads of supinator).
Runs dorsolaterally between two heads. Passes around neck of humerous (with deep supinator lying on top).
Enterors extensor compartment of elbow.
Enters plane between deep abductor pollicis longus + superficial extensor digitorum/minimi superficially. (and running a course parrel and atop the radius.
Joined by posterior interosseous artery.
Runs over extensor pollicis brevis dives under Extensor pollicis longus.
At midhumerous runs along interosseous membrane.
*Superficial Branch of Radial Nerve**
Originates at radiocapetellar joint.
Course down parallel to brachioradialis. Lies in plane underneath brachioradialis. On top of pronator teres + supinator.
Lies Lateral to the radial artery.
Pops out from under brachioradialis approximately 7 cm proximal to the radial styloid. To do so runs up between brachioradialus and ECRL. (warburton's syndrome). Then peirces deep fascia at 5cm from styloid .
Runs near cephalic vein superficially (just inferior).
Runs over snuff box roof to supply dorsal radial surface of hand
then divides into two branches: medial and lateral.
the medial branch is the larger of the terminal branches of the superficial radial nerve and innervates
index,middle fingers and the radial aspect of the fourth finger;
also does medial aspect thumb.
Lateral does lateral aspect of thumb. + dorsal surface of the base of the thumb
Radial Cutaneous Innervation
Imagine limb divided into 3rds on arm and forearm and hand.
It does the middle 3rd of arm and forearm. (posterior cutaneous nerve of forearm (axilla), post cut nerve of arm)
Also does the lateral 3rd of lower arm. Lower lateral cutaneous nerve of arm.
cubital fossa bifurcation
Lies under brachioradialis on supinator, pronator quadratus FDS
Distally it lies only underneath deep fascia, in between brachioradialis and FCR.
Radial recurrent artery -
arises @ radials commencement.
It's recurrent - anastomose with the radial collateral artery.
Palmar carpal branch of radial artery -
arises near the lower border of the pronator quadratus.
anastamoses with the palmar carpal branch of the ulnar + anterior interosseous arteries.
forms the palmar carpal arch
Dorsal Carpal Branch.
branches proximal anatomical snuffbox.
runs medially across wrist.
Forms deep palmer arch of hand.
Superficial palmar branch of the radial artery - arises from the radial artery, just as it winds around lateral wrist.