All are true about brachial plexus EXCEPT:-
Contribution by C4 to brachial plexus is pre-fixed brachial plexus. Post-fixed brachial plexus has contribution by T2 Brachial plexus is formed by the anterior primary rami of C5, 6, 7, 8 & T1 It consists of roots, trunks, cords, divisions and branches. A total of 17 branches are given off from the plexus including 2 from roots, 2 from trunks and 13 from cords.
Lower trunk is formed by root C8 and T1
Lateral cord is formed by upper and middle trunk
Posterior cord is formed by posterior divisions of all three trunks
C4 root is post fixed to plexus
Nerve supply, Nerve Lesions