Brachial plexus and nerves of upper limb (infraclavicular branches)

Question 1

What is the origin of the lateral pectoral?

Answer 1

Side branch of lateral cord, recieving fibers from C5, C6 and C7

Question 2

What is the course of the lateral pectoral?

Answer 2

Peirces costocoracoid membrane to reach deep surface of pectoral muscles; a communicating branch to the medial pectoral nerve passes anterior to axillary artery and vein

Question 3

What are the structures innervated by the lateral pectoral?

Answer 3

Primarily pectoralis major; but some lateral pectoral nerve fibers pass to pectoralis minor via branch to medial pectoral nerve

Question 4

What is the origin of the musculocutaneous?

Answer 4

Terminal branch of lateral cord, recieving fibers from C5 - C7

Question 5

What is the course of the musculocutaneous?

Answer 5

Exits axilla by peircing coracobrachialis; descends between biceps brachii and brachialis, supplying both; continues as lateral cutaneous nerve of forearm

Question 6

What are the structures innervated by the musculocutaneous?

Answer 6

Muscles of anterior compartment of arm; skin of lateral aspect of forearm