Muscles of the pectoral region

Question 1

what are the 4 muscles in the pectoral region?

Answer 1

pectoralis major, pectoralis minor, serratus anterior and subclavius

Question 2

origin of the pectoralis major

Answer 2

clavicular head- anterior surface of the medial clavicle
sternocostal head- anterior surface of the sternum, superior 6 costal cartilages and aponeurosis of the external oblique muscle

Question 3

insertion of the pectoralis major

Answer 3

interlobular sulcus of the humerus

Question 4

function of the pectoralis major

Answer 4

adducts and medially rotates the upper limb and draws the scapula anteroinferiorly.
clavicular head- individually flexes the upper limb

Question 5

innervation of the pectoralis major

Answer 5

lateral and medial pectoral nerves

Question 6

origin of the pectoralis minor

Answer 6

3rd,4th and 5th ribs

Question 7

insertion of the pectoralis minor

Answer 7

coracoid process of the scapula

Question 8

innervation of the pectoralis minor

Answer 8

medial pectoral nerve

Question 9

function of the pectoralis minor

Answer 9

stabilises the scapula (draws it anteroinferiorly against the thoracic wall)

Question 10

origin of the serratus anterior

Answer 10

ribs 1-8 (consists of several strips)

Question 11

insertion of the serratus anterior

Answer 11

costal surface (rib facing) surface of the medial border of the SCAPULA

Question 12

innervation of the serratus anterior

Answer 12

long thoracic nerve (comes of the brachial plexus)

Question 13

function of the serratus anterior

Answer 13

rotates the scapula, allowing the arm to be raised over 90 degrees
also holds the scapula against the ribcage

Question 14

origin of the subclavius

Answer 14

junction of the 1st rib and its costal cartilage

Question 15

insertion of the subclavius

Answer 15

inferior surface of the middle third of the clavicle

Question 16

innervation of subclavius

Answer 16

subclavian nerve (C5-C6)

Question 17

function of subclavius

Answer 17

anchors and depresses the clavicle