The triceps brachii muscle is the only muscle in the posterior compartment of the arm. It consists of three heads: lateral, medial and long head and serves primarily to extend the forearm. Learn more about the anatomy of the triceps brachii using the narrated video tutorial and interactive 3D anatomy model.
- Long head: infraglenoid tubercle of scapula
- Lateral head: above the radial groove (posterior humeral surface)
- Medial head: below the radial groove (posterior humeral surface)
- Olecranon process of the ulna.
- Primarily extends forearm at the elbow joint
- Long head: extension and adduction of the arm at the shoulder joint
- Radial nerve (C6,7,8)
- Long head innervated by the axillary nerve
- Deep brachial artery
- Posterior circumflex humeral artery