An intracorporeal portion of a percutaneous device for a joint disarticulation prosthesis or joint replacement prosthesis, the intracorporeal portion having an extracorporeal portion or having means for rigidly coupling directly to an extracorporeal portion, the extracorporeal portion being for location exterior to the skin, the intracorporeal portion having an articulating component for articulating with an articulating surface, wherein the articulating component is intracorporeal when installed in a human or animal subject.