which nerve innervates the extensor muscles in the arm and forearm
The radial nerve is a nerve in the human body that supplies the posterior portion of the upper limb. It innervates the medial and lateralheads of the triceps brachii muscle of the arm, as well as all 12 muscles in the posterior osteofascial compartment of the forearm and the associated joints and overlying skin.uscles of the posterior forearm. All the labelled muscles (that is, all the visible muscles except the ones on the dorsal hand and one at top left) are innervated by the radial nerve, and represent all muscles innervated by the radial nerve except for the supinator.