Muscle causing supination of forearm

SUPINATION & PRONATION OF FOREARM:-Perform skilled movements.Elbow is semiflexed in mid prone position.Palm turned down in pronation and upwards in supination.Rotatory movement of forearm which occur at superior and inferior radioulnar joints around a veical axis.In supination, radius and ulna lie parallel to each other.In pronation, rotation of lower end of radius on the head of ulna.Supination more powerful than pronation., because it has antigravity movement, it is performed by powerful muscles.Muscles involved:-Supination:-1. Supinator.2. Biceps brachii- supinates when elbow is flexed.3. Brachioradialis-supinates pronated forearm to midprone position.Pronation:-1. Pronator teres.2. Pronator quadratus.3. Brachioradialis- pronates the supinated forearm to midprone position .{Reference:vishram singh, pg no.145}