The Brachioradialis functions as a flexor of the elbow joint and assists in pronation and supination. It lies in the anterior aspect of the forearm but receives innervation from the radial nerve. The neutral position for the brachioradialis is halfway between pronation and supination with the elbow flexed. It does not cross the wrist and therefore has no action on that joint.
To test the brachioradialis muscle, have the patient flex the elbow joint against
resistance with the thumb pointed toward the ceiling. A normally functioning
muscle is rendered prominent.