Pectoral and Upper Arm Muscles

Question 1

Pec major

Answer 1

Origin - Medial side of the clavicle, manubrium and body of sternum and costal cartilage of ribs 1-6

Insertion - Greater Tubercle

Innervation - Medial and lateral pec nerve

Action - Adduction, flexion and internal rotation

Question 2

Pec Minor

Answer 2

Origin - 3rd, 4th and 5th ribs

Insertion - coracoid process

Innervation - medial pectoral nerve

Action - Pulls scapula medialy, forward and downwards

Question 3

Serratus Anterior

Answer 3

Origin - 1st to 9th ribs

Insertion - medial margin of the costal surface of the scapula

Innervation - long thoracic nerve

Action - rotation of the scpaula allowing abduction passed 90 degrees

Question 4

Subclavius

Answer 4

Origin - Costal cartilage of 1st rib

Insertion - acromial end of the clavicle

Innervation - subclavian nerve

Action - draw clavicle downwards and forwards

Question 5

Tricep Brachii long head

Answer 5

Origin - Infraglenoid tubercle of the scapula

Insertion - olecrannon of the ulna

Innervation - radial nerve

Action - extension of the shoulder and elbow and adduction of the shoulder

Question 6

Tricep Brachii lateral head

Answer 6

Origin - Posterolateral surface of the humerus proximal to the radial groove

Insertion - olecrannon of the ulna

Innervation - radial nerve

Action - extension of the forearm

Question 7

Tricep Brachii medius

Answer 7

Origin - Posteromedial surface of the distal humerus below the radial groove

Insertion - olecrannon of the ulna

Innervation - radial nerve

Action - extension of the forearm

Question 8

Biceps Brachii long head

Answer 8

Origin - Supraglenoid tubercle of the scapula

Insertion - Radial tuberosity

Innervation - Musculocutaneous nerve

Action - Supination and flexion of the forearm

Question 9

Biceps Brachii short head

Answer 9

Origin - Coracoid process

Insertion - Radial tuberosity

Innervation - Musculocutaneous nerve

Action - Supination and flexion of the forearm

Question 10

Coracobrahcialis

Answer 10

Origin -Coracoid process

Insertion - upper 1/3rd of the frontal humerus

Innervation - Musculocutaneous nerve

Action - Flexion of the shoulder

Question 11

Brachialis

Answer 11

Origin - Distal anterior surface of the humerus

Insertion - tuberosity of the ulna

Innervation - Musculocutaneous nerve

Action - Flexion of the forearm