Muscle
Supinator
Supinates the extended forearm
High-yield
Deep radial (posterior interosseous) nerve passes through it - site of posterior interosseous nerve entrapment.
Overview
A deep muscle wrapping the proximal radius that supinates the forearm; the deep radial nerve passes through it (arcade of Frohse).
Reference facts
- Origin
- Lateral epicondyle of humerus, radial collateral and anular ligaments, and supinator crest of the ulna
- Insertion
- Lateral, posterior, and anterior surfaces of the proximal radius
- Action
- Supinates the forearm (works with biceps when elbow flexed)
- Innervation
- Deep branch of the radial nerve (C7, C8)
- Blood supply
- Recurrent interosseous / radial arteries
Frequently asked questions
What does the supinator do?
The supinator supinates the forearm (works with biceps when elbow flexed).
What nerve innervates the supinator?
The supinator is innervated by the deep branch of the radial nerve (C7, C8).
Where does the supinator attach?
The supinator originates from the lateral epicondyle of humerus, radial collateral and anular ligaments, and supinator crest of the ulna and inserts on the lateral, posterior, and anterior surfaces of the proximal radius.
What is the blood supply of the supinator?
The supinator is supplied by the recurrent interosseous / radial arteries.