- Assists triceps in extending forearm.
- Stabilizes elbow joint.
- Abducts ulna during pronation.
- Lateral epicondyle of humerus.
- Lateral surface of olecranon and superior part of posterior surface of ulna.
- Radial nerve (C7, C8 and T1).
- The continuation of the deep branch of the radial nerve.
Arterial Supply :
- Middle collateral branch of deep brachial artery.
- Recurrent interosseous artery.