3 Answers

If the doctor erred during the surgery, they yes. That's doctor negligence, not a risk involved in the surgery. Doctor error is not part of the listed risks. Go get a lawyer. 

If doctor error was allowed, then they would not even need a degree. They could do whatever they wanted and as sloppily as they wanted and say "Oh well, you took the risk that I would not do as good a job as I could". Apply this logic to anything and nothing in this world would be done correctly. You signed a consent allowing him to do the surgery. You did not sign a consent that allowed him to make mistakes. 

I don't think you can, that's why the doctor had you sign the form in the first place. It will take an awful lot of lawyering......

Interesting question - if the mistake was not one of the risks explained when the consent form was signed then yes. You would need an expert witness to decide if one of the risks could result in this kind of mistake. There are risks and definately mistakes - the differentiation is important. Even if you do not have a copy of the risks explained to you there will be standard documentation of these risks.