- Discussion:
- origin:
- lateral epicondyle of humerus, radial collateral ligament of elbow, annular ligaments of radius and the supinator crest of ulna;
- insertion:
- oblique line on the lateral anterior surface of the upper 1/3 of radius;
- supinator covers the upper third of the radius;
- action: supinates the forearm;
- nerve supply: radial (PIN branch), C5, C6
- PIN supplies ECRB and supinator muscles before entering arcade of Froshe;
- PIN brach travels thru the substance of the supinator;
- w/ humerus frx, need to r/o radial nerve palsy;
- first branches distal to frx site will be ECRB & supinator;
- synergists:biceps brachi