Pectoralis Major

Question 1

Pectoralis Major (ORIGIN)

Answer 1

Clavicular head: medial half of the clavicle
Sternocostal head: Anterior surface of the sternum, superior six costal cartilages, and aponeurosis of the external oblique muscle

Question 2

Pectoralis Major (INSERTION)

Answer 2

Lateral lip of the intertubercular sulcus of the humerus)

Question 3

Pectoralis Major (INNERVATION)

Answer 3

Lateral and medial pectoral nerves (C5-T1)

Question 4

Pectoralis Major (BLOOD SUPPLY)

Answer 4

Thoracoacromial artery (pectoral branch) and the internal thoracic artery

Question 5

Pectoralis Major (ACTION)

Answer 5

Adducts, medially rotates, and flexes the arm (clavicular head); extends the arm from a flexed position (sternocostal head)