Pectoral Region

Question 1

What nerve innervates the pectoralis major muscle?

Answer 1

Lateral and medial pectoral nerves (c5, C6)

Question 2

What is the action of the pectoralis major muscle?

Answer 2

Adducts and medially rotates humerus, draws scapular anteriorly and inferiorly

Question 3

What is the blood supply to the pectoralis major?

Answer 3

Pectoral and deltoid branch of the thoracoacromial artery

Question 4

What is the nerve supply of the pectoralis minor?

Answer 4

Medial pectoral nerve (C8, T1)

Question 5

What is the action of the pectoralis minor?

Answer 5

Draws scapula inferiorly and anteriorly against thoracic wall

Question 6

What is the blood supply to the pectoralis minor?

Answer 6

Pectoral and deltoid branches of the thoracoacromial artery

Question 7

What is the nerve supply to the subclavius?

Answer 7

Nerve to subclavius (c5, c6)

Question 8

What is the action of the subclavius?

Answer 8

Anchors and depresses the clavicle

Question 9

What is the blood supply to the subclavius?

Answer 9

Clavicular branch of the thoracoacromial artery

Question 10

What is the nerve supply of the serratus anterior?

Answer 10

Long thoracic nerve (c5, C6, C7)

Question 11

What is the action of the serratus anterior?

Answer 11

Protracts scapula, rotates scapula (allows abduction of glenohumeral past 90 degrees)

Question 12

If there is damage to the long thoracic nerve what happens and why?

Answer 12

‘Winged scapula’ upon full extension (arms out in front of you)

Because the serratus anterior muscle is paralysed and cannot rotate scapula