Like the definition you posted, only not as encompassing:
"Violence occurs when one person harms, or threatens to harm, another person's body, feelings, or property."
This definition was up in a school where I volunteered, followed by: "Violence in any form will not be tolerated here." I like MLK's point that violence can also be in our hearts as well as in our words and deeds.
I disagree with awediot's statement that words can never be violent. I find it much more violent to attack a person's dignity and worth than to punch them in the face. Too many lives are ended by suicide resulting from verbal assaults.
In your "quiz," I can't see the surgery as violent. The patient (presumably) consented to it with full knowledge of the procedure and risks. She didn't just "lay down and take it," but was in a position where she was offered a true choice, one where she simply had to express her will one way or the other, and chose the surgery.