Expansion
Pronators are pronator teres and pronator quadratus; supinators are supinator and biceps brachii
Expansion
Pronation (palm down):
- Pronator teres
- Pronator quadratus
Supination (palm up):
- Supinator
- Biceps brachii (strongest, with the elbow flexed)
The pronators are median nerve territory; supinator is supplied by the deep branch of the radial nerve and biceps by the musculocutaneous nerve.