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.
| Origin | - Long head: infraglenoid tubercle of scapula
- Lateral head: above the radial groove (posterior humeral surface)
- Medial head: below the radial groove (posterior humeral surface)
|
|---|
| Insertion | - Olecranon process of the ulna.
|
|---|
| Innervation | - Radial nerve (C6,7,8)
- Long head innervated by the axillary nerve
|
|---|
| Blood Supply | - Deep brachial artery
- Posterior circumflex humeral artery
|
|---|
| Action | - Primarily extends forearm at the elbow joint
- Long head: extension and adduction of the arm at the shoulder joint
|
|---|
