Brachial plexus - C4- T1

Question 1

Axillary

Answer 1

C5, C6
Formed from posterior cord, posterior division of the brachial plexus
Motor Innervation: Deltoid (arm abductor)
Teres minor (lateral rotator of arm)
cutaneous innervation: superolateral arm

Question 2

Median Nerve

Answer 2

Formed from medial and lateral cords, anterior division of the brachial plexus
C5–T1
MI: Most anterior forearm muscles
CI: Palmar aspects and dorsal tips of lateral 3-1/2 digits (thumb, index finger, middle finger, and 1/2 of ring finger)


Question 3

Musculocutaneous Nerve

Answer 3

Formed from the lateral cord, anterior division of the brachial plexus

C5 - C7
MI: Anterior arm muscles (flex humerus, flex elbow joint, supinate forearm)
CI: Lateral region of forearm


Question 4

Radial Nerve

Answer 4

C5 - T1
Formed from the posterior cord, posterior division of the brachial plexus
MI: Posterior arm muscles (extend forearm) Posterior forearm muscles(supinate forearm, extend wrist, digits, onemuscle that abducts thumb)
CI: Posterior region of arm
Posterior region of forearm
Dorsal aspect of lateral three digits (except their distal tips)


Question 5

Ulnar Nerve

Answer 5

C8–T1
MI: Anterior forearm muscles
Medial 1/2 of flexor digitorum profundus
Intrinsic hand muscles Hypothenar muscles
Medial two lumbricals (flex MP joints and extend
CI: Dorsal and palmar aspects of medial 1-1/2 digits (little finger, medial aspect of ring finger)