What are the attachments of the pectoralis major muscle?
a. Superior it attaches at the level of the medial half of the anterior
surface of the clavicle
b. Superior it attaches at the level of the acromion process of the
scapula
c. Medial it attaches at the level of the first seven costal cartilages
d. Lateral it attaches at the level of the lateral lip of the intertubercular sulcus of the humerus
e. Lateral it attaches at the level of
the medial lip of the intertubercular sulcus of the humerus
16. The innervation of the pectoralis major muscle is done by:
a. Long thoracic nerve
b. Lateral pectoral nerve
c. Intercostal nerves
d. Accessory nerve
e. Medial pectoral nerve
The correct answers are:
Attachments:
– a. Superior: it attaches at the level of the medial half of the anterior surface of the clavicle
– c. Medial: it attaches at the level of the first seven costal cartilages
– e. Lateral: it attaches at the level of the lateral lip of the intertubercular sulcus of the humerus
Innervation:
– b. Lateral pectoral nerve
– e. Medial pectoral nerve
So, the pectoralis major muscle attaches to:
– The clavicle (medial half of the anterior surface)
– The costal cartilages (first seven)
– The humerus (lateral lip of the intertubercular sulcus)
And is innervated by the lateral and medial pectoral nerves.
Note: The pectoralis major muscle has two heads, the clavicular head and the sternocostal head, which attach to different points and are innervated by different nerves.