Check out this article:
https://www.forbes.com/sites/kristinakillgrove/2018/04/12/archaeologists-find-ancient-knife-hand-prosthesis-on-medieval-warrior/#69bb959e3915
Basically, they found a medieval skeleton who was missing an arm and appears to have replaced it with a prosthetic knife. Additionally, alterations to his shoulder and the condition of his teeth and jaw seems to indicate, according to the article, that he was maybe "'tightening the prosthesis with his teeth.'"
Now, if that isn't material for a character in a story, I'm not sure what is.