The state of peripheric and central parts of neuromuscular system in patients with traumas of nerves of the forearm after the operations is examined by electrophysiologic methods. The changes of motor and central caused responces of the short abductor of the first finger are detected, pointing at the participation of median and ulnar nerves in the reinnervation of this muscle and the existence of functional shifts in the state of motor centers of the muscles of injured and uninjured limbs.