Triceps Brachii Muscle

Triceps Brachii

-only muscle in posterior compartment of brachii -very powerful -antagonistic muscle: to brachialis -Break/Injury: more inferior injury- the better; more superior injury- the worse

Triceps Brachii Origin

1. Long head: infraglenoid tubercle of the scapula 2. lateral head: upper half of the posterior surface of the shaft of the humerus 3. Medial head: posterior surface of the lower half of the shaft of the humerus

Triceps Brachii Innervation

Radial nerve (C7, C8) (lies on surface of radial grove of humerus)

Triceps Brachii Action

extends forearm long head aids in adduction if arm is abducted

Triceps Brachii Insertion

posterior part of olecranon process (all three blend together) of ulna