Muscles of the Arm Flashcards
What three muscles make up the anterior arm?
Biceps brachii, Coracobrachialis, brachialis
all three are supplied by musculocutaneous nerve
What two muscles make up the posterior arm?
Triceps brachii and anconeus
both supplied by Radial nerve
Where is the Cephalic vein located?
may be located in the deltopectoral groove
What is the deep fascia of the arm called?
Brachial fascia
What is the deep fascia of the forearm called?
antebrachial fascia
What vein is a common site of peripheral blood draw?
The medial cubital vein because it is separated from deeper structures by the bicipital aponeurosis in the cubital fossa
What protects deeper structures during blood draw?
bicipital aponeurosis
What is the origin, insertion, innervation, and action of the biceps brachii?
Origin: long head- supraglenoid tubercle of scapula
short head-coracoid process
Insertion: radial tuberosity; bicipital aponeurosis into fascia of forearm
Innervation: Musculocutaneous
action: flex humerus at shoulder(long head)
flex forearm to elbow
supinate forearm
When is bicep brachii most effective?
When the forearm is supinated
What is the origin, insertion, innervation, and action of the Brachialis?
origin: distal humerus
insertion: coronoid process and tuberosity of the ULNA
Innervation: Musculocutaneous
action: it is the “workhorse” of flexion and flexes the elbow
What is the origin, insertion, innervation, and action of the Brachioradialis?
origin: supracondylar ridge of humerus
insertion: distal radius
Innervation: radial nerve
action: flexes the elbow when the forearm is in the neutral position (the drinking muscle)
What is the origin, insertion, innervation, and action of the Coracobrachialis?
origin: coracoid process
insertion: mid-humerus, medial surface
Innervation: musculocutaneous nerve pierces the muscle
action: flexes arm at the shoulder
What is the origin, insertion, innervation, and action of the tricep brachii?
origin: Long head: infraglenhoid tubercle of scapula;lateral head: posterior shaft of humerus superior to radial groove;medial head : posterior shaft of humerus inferior to radial groove
insertion: olecranon process of ulna
Innervation: radial nerve
action: extend elbow; long head extends the shoulder
What is the origin, insertion, innervation, and action of the Anconeus?
origin: lateral epicondyle of humerus
insertion: superior ulna, lateral surface of olecranon
Innervation: radial nerve
action: assist triceps in elbow extension
What kind of extension does the tricep and bicep allow?
controlled extension
