Muscles Of Anterior & Lateral Trunk

Question 1

Pectoralis Major

Answer 1

Origin: Clavicle, sternum, & costal cartilages

Insertion: Lateral lip of intertubercular groove of humerus

Action: Adduction of arm

Question 2

Pectoralis Minor

Answer 2

Origin: Rib 3-5

Insertion: Coracoid process of scapula

Action: Fixates scapula

Question 3

External Intercostals

Answer 3

Origin: Inferior border of rib above

Insertion: Superior border of rib below

Action: Elevation of ribs for inspiration

Question 4

Internal Intercostals

Answer 4

Origin: Superior border of rib below

Insertion: Inferior border of rib above

Action: Depression of ribs for expiration

Question 5

Serratus Anterior

Answer 5

Origin: Ribs 1-9

Insertion: Vertebral (medial) border of the scapula

Action: Abducts scapula; elevates ribs