A: It means the attorney for the doctor or hospital has asked a court to dismiss your claims before you ever get to trial. It's a pre-emptive strike to get your case thrown out before you have a chance to present your case to a jury.
In order to have a chance at being successful in getting your case thrown out, a defense lawyer must present convincing proof to the court that your case has no merit. They must support their request with pre-trial testimony, with documents and evidence. The victims' attorney must present papers that oppose this request.
In order to do that, your lawyer must present expert medical proof that you do have a valid and meritorious case and must go into specific details of how and why they believe that to be true.
When the court is faced with competing medical experts, who both offer compelling arguments for and against, the judge is likely to deny the request to dismiss the case prematurely and instead let a jury decide the issue at trial.