Muscles Of The Arm

Question 1

Biceps brachii origin

Answer 1

Radial tuberosity (flexes elbow joint as this attaches in the forearm)

Question 2

Biceps brachii innervation

Answer 2

Musculocutaenous n (C5-6)

Question 3

Biceps brachii action @ each joint

Answer 3

Shoulder: flexion,abduction and internal rotation, stability on of humeral head during deltoid contraction,
Elbow: flexion and supination

Question 4

Brachialis origin

Answer 4

Humerus-distal 1/2 anterior surface

Question 5

Brachialis insertion

Answer 5

Ulnar tuberosity

Question 6

Brachialis innervation

Answer 6

Musculocutanenous n C5-6 and radial nerve C7-minor

Question 7

Brachialis action

Answer 7

Flexion @ elbow

Question 8

Triceps origin

Answer 8

Long head: infraglenioid tubercle of the scapula
Medial head: posterior humerus, inferior to radial groove, medial inter muscular septum
Lateral head: posterior humerus, proximal to radial groove, lateral intermuscular septum

Question 9

Triceps insertion

Answer 9

Olecranon of ulna

Question 10

Triceps innervation

Answer 10

Radial nerve C6-8

Question 11

Action of triceps

Answer 11

@ elbow: extension

@shoulder: long head does extension and adduction

Question 12

Aconeus origin

Answer 12

Lateral epicondyle of humerus

Question 13

Aconeus insertion

Answer 13

Olecranon of ulna-radial surface

Question 14

Innervation of aconeus

Answer 14

Radial nerve C6-8

Question 15

Action of aconeus

Answer 15

Extends the elbow and tightens joint

Question 16

Biceps brachii origin

Answer 16

Long head: supraglenoid tubercle of scapula

Short head: coracoid process of scapula