Muscles of the Arm

Question 1

Muscles of the anterior compartment: BICEPS BRACHII

Answer 1

Origin: two heads
Long head - supraglenoid tubercle
Short head - coracoid process
Insertion: radial tuberosity, bicipital aponeurosis (fascia of anterior compartment of the forearm)
Innervation: musculocutaneous nerve
Action: flexion of arm, flexion and supination of forearm

Question 2

Muscles of the anterior compartment: BRACHIALIS

Answer 2

Origin: anterior surface of humerus
Insertion: ulnar tuberosity
Innervation: musculocutaneous nerve
Action: flexion of forearm

Question 3

Muscles of the anterior compartment: CORACOBRACHIALIS

Answer 3

Origin: coracoid process
Insertion: medial surface of humerus
Innervation: musculocutaneous nerve
Action: flexion of arm at GHJ

Question 4

Muscles of the posterior compartment: TRICEPS BRACHII

Answer 4

Origin: three heads
Long head - infraglenoid tubercle
Medial head - posterior surface of humerus inferior to radial groove
Lateral head - posterior surface of humerus superior to radial groove
Insertion: olecranon
Innervation: radial nerve
Action: extension and adduction of arm at GHJ, extension of forearm

Question 5

Muscles of the posterior compartment: ANCONEUS

Answer 5

Origin: posterior surface of lateral epicondyle of humerus
Insertion: posterior surface of ulnar
Innervation: radial nerve
Action: assists elbow extension