The next step the doctors want to do is eyes and legs. From there who knows what else is possible. The point is - we are not our bodies. The body is mechanical much like the prosthetic arm.
To move your body doesn't take much thought, but it does take thought. Some day it will be possible to connect a complete functioning body with arms, legs, eyes, ears, vocal cords, etc. to a brain.
However, the thing that is irreplaceable is the mind that extends beyond the brain and the body. Even though you are not your body the True You is forever connected to the universal mind.