Most states in the US have laws about timing a medical liability law suit. It tends to be 2 yrs. If you pass that time period you are sunk (it is called statute of limitations). You'd have to check with your own state's laws. Many liability attorneys give you a free first visit to evaluate you.

However, egregious negligence can always be reported to your State's medical licensing board. Doctors who do not conform to "standard of care" may be disciplined that way. There is no time limit for this procedure that I am aware of. Don't bother with the AMA...it does nothing about things like this.