The idea of replacing a dysfunctional or missing body part with a prosthesis is perhaps as old as the history of humankind; yet, it still continues to be a fascinating theme. While early prostheses were limited to external organs (. wooden legs), the twentieth century witnessed the implantation of numerous devices inside the human body, some of which have since become routine surgical procedures. For external prostheses, both proper fitting and functionality are needed to make a device acceptable for use; however, internally implanted prostheses have additional challenges, and the implantation of intelligent devices which interact with surrounding tissues is even more difficult
