oh dear! How scary!

Good luck with the op, i would say you have abig case of lack of informed consent for sure.. there would be someone you could call (a medical board or something like that- just do a google search) and atleast ask them if they think you would have a case. i would ask for a copy of your medical records too, just to see what is wrtten in the notes about the insertion and informed consent.
I manage a dental surgery and we get written consent for everything with our patients, have never had anything go wrong or anything like that but just covering us if there ever was a problem.