Chest/Axillary

Question 1

Pectoralis Major

Answer 1

PA: med ½ clavicle along ant portion, sternum along ½ ant surface, 1‐7 costal cartilage, sternal end of 6th rib & aponeurosis of EAO

DA: lat lip of bicipital groove

Innervation: med and lat pectoral clavicular fibers (C5,6); sternal fibers (C6‐T1)

Actions: OC‐ Humeral adduction & medial rot.
clavicular fibers: flex an extended arm
sternal fibers: extend a flexed arm
CC‐ draws trunk upward & forward

Question 2

Pectoralis Minor

Answer 2

PA: ribs 3‐5 along upper margins & outer surfaces near costal cartilage, fascia over adjoining ext. intercostal mm.

DA: coracoid process along med border & upper surface

Innervation: med and lat pectoral (C5‐T1)

Actions: Scapular depression assists with protraction

Question 3

Subclavius

Answer 3

PA: 1st rib at junction of rib and its costal cartilage

DA: groove on middle 1/3 of clavicle’s inferior surface

Innervation: nerve to Subclavius (C5,6)

Actions: OC‐ Shunting (approximating) the clavicle towards the manubrium during violent extremity motions such as throwing or hitting). Also produces clavicular depression & protraction: CC‐ secondary mm of respiration