Ged Galvin, 55, now presses a remote control to open his bowels and go to the toilet.
The IT project manager from Barnsley, south Yorkshire, almost died when an off-duty police officer pulled out in front of him in her car.
Mr Galvin suffered massive internal injuries and had to be fitted with a colostomy bag until surgeons at the Royal London Hospital could perform the complex operation to rebuild his bottom.
The medical team took a muscle from above his knee, wrapped it around his sphincter, and then attached electrodes to the nerves.
These are now operated by a palm-sized remote control that he carries in his pocket.
“It’s like a chubby little mobile phone,” he said. “You switch it on and off, just like switching on the TV.
It would be a darn shame if some hacker was able to find the frequency of that remote.