The authors present a technique of direct muscular neurotization consisting of re-innervation by direct implantation of a nerve into one or several muscles in cases of avulsion of the nerve supplying the muscle or traumatic or surgical avulsion of the neural part of the muscle. The biological basis for this operation is that a denervated muscle can accept a new innervation by a foreign nerve even in an aneural zone because its sensitivity to acetylcholine is present throughout the muscle, while, in a normally innervated muscle, sensitivity to acetylcholine is confined to the motor endplates. The results of 47 cases are presented: 42 of them obtained good or very good results.