Upper arm muscles

Question 1

What are the four muscles of the upper arm?

Answer 1

(posterior) - triceps brachii

(anterior) - biceps brachii, brachialis and coracobrachialis

Question 2

What 3 arm muscles does the musculocutaneous nerve innervate?

Answer 2

BBC!!

biceps brachii, brachialis, coracobrachialis

Question 3

Attachments/origins of the biceps brachii

Answer 3

long head- supraglenoid tubercle of the scapula

short head- coracoid process of the scapula

Question 4

Insertion of the biceps brachii

Answer 4

Radial tuberosity and fascia of the forearm via the bicipital aponeurosis

Question 5

Functions of the biceps brachii

Answer 5

Supination of the forearm and flexion

Question 6

Origin of the coracobrachialis

Answer 6

coracoid process of the scapula

Question 7

Attachments of the coracobrachialis

Answer 7

coracoid process of the scapula and the medial side of the humeral shaft

Question 8

origin of the brachialis

Answer 8

medial and lateral surfaces of the humeral shaft

Question 9

Insertion of the brachialis

Answer 9

ulnar tuberosity (just distal to the elbow joint)

Question 10

arterial supply of the anterior muscles

Answer 10

brachial artery

Question 11

How many heads does the triceps brachii have?

Answer 11

3 but the medial head lies deeper than the other two, which cover it

Question 12

innervation of triceps brachii

Answer 12

radial nerve

note- in some individuals the long head of the triceps brachii is innervated by the axillary nerve

Question 13

origins of the triceps brachii

Answer 13

long head- infraglenoid tubercle of scapula
lateral head- humerus (superior to the radial groove)
medial head- humerus (inferior to the radial groove)

Question 14

insertion of the triceps brachii

Answer 14

the heads converge onto one tendon and insert in the olecranon of the ulna

Question 15

Function of the biceps brachii

Answer 15

Supination of forearm.

Flexes the arm at the elbow and at the shoulder

Question 16

function of the coracobrachialis

Answer 16

flexion of the arm at the shoulder and weak adduction

Question 17

function of the brachialis

Answer 17

flexion at the elbow

Question 18

function of the triceps brachii

Answer 18

extension of the arm at the elbow