Anterior Axioapendicular Muscles

Question 0

Pectoralis minor

Answer 0

Medial: 3-5th ribs at their costal cartilages

Lateral: medial border of superior surface of coracoid process

Innervation: medial pectoral nerve (C8 and T1)

Action: stabilizes scapula by drawing inferiorly and anteriorly against thoracic wall

Question 1

Pectoralis major

Answer 1

Medial: clavicular head - anterior surface of the medial half of the clavicle; sternocostal head - anterior surface of sternum, superior six costal cartilages, and aponeurosis of external oblique muscles

Lateral: lateral lip of the intertubercular sulcus of the humerus

Innervation: lateral and medial pectoral nerve - clavicular head (C5,C6) and sternocostal head ( C7,C8,T1)

Action: ADD and medial rotation of humerus and draws scapula anteriorly and inferiorly; (unilaterally) clavicular head flexes humerus and sternocostal head extends it from a flexed position

Question 2

Subclavius

Answer 2

Medial: junction of 1st rib and its costal cartilage

Lateral: inferior surface and middle third of the clavicle

Innervation: subclavian nerve (C5,C6)

Action: anchors and depresses the clavicle

Question 3

Serratus anterior

Answer 3

Medial: external surface of lateral parts of 1st-8th ribs

Lateral: anterior surface of medial border of scapula

Innervation: long thoracic nerve (C5,C6,C7)

Action: protracts scapula and holds it against thoracic wall and rotates scapula