Although I'm licensed in Illinois, I believe the statute of limitations for medical malpractice in Pennsylvania is two years from the date of injury, with some limited exceptions. My guess is that you've missed your opportunity to sue, but call a local medical malpractice attorney to make sure. You should be able to do this for free.
How long you have to contact a lawyer depends upon the nature of your inquiry. In general, in Pa. a victim of malpractice has two years from the time of the negligently caused injury. There are exceptions to this general rule. One obvious exception involves claims of children. A child's claim is preserved until two years following their eiteenth birthday. The discovery rule ( http://bit.ly/QeAiD) is more complicated but can be found at the url I placed in parentheses. Just copy and paste in your browser. There is also a Statute of repose which may alswo have bearing on your potential case. See same site http://bit.ly/QeAiD for details.
Malpractice cases are very fact dependent and need to be evaluated by an attorney with experience in handling such matters and also familiar with the very restrictive laws in Penna. governing such cases.
In a previous answer to this question I proovided links where further information could be obtained concerning time limitations for filing medical malpractice claims in Pennsylvania. The links were incorrect. the proper links where further reliable information can be obtained http://bit.ly/1WYoS t I'm sorry for any inconvenience this may have caused