Time course of the regeneration of the endplate zone after autologous muscle transplantation.

Reinnervation of transplanted muscles occurs in 2 steps. During the first 5 months the motor axon terminals innervate primarily the border of the original endplate zone, re-establishing its previous outline. In the next 4 months, by further ramifying of the axons, new nerve-muscle contacts are formed exclusively within the boundaries of this zone.