Extensor carpi radialis brevis muscle
The extensor carpi radialis brevis muscle is innervated by the posterior interosseous nerve, C7 and C8.
- extensor, because the muscle extends the wrist when contracted.
- carpi, meaning wrist, referring to the insertion point.
- radialis, meaning bone, because it is on the side of the arm with the radius, distinguishing it from the extensor carpi ulnaris muscle.
- brevis, meaning short, differentiates it from the extensor carpi radialis longus muscle, which is longer and performs a similar action.