How? He had the entire of Terri's medical records at his use when he had his sessions with Terri. What those records show is a schedule and results of the therapies she received 'back then'.
"What those records show is a schedule and results of the therapies she received 'back then'."
So lets see, the records themselves are not brought into evidence by the Schievo's ( where are they ? ) nor anyone who actually performed them, but some Dr who read the reports 10 years later can "confirm" them.
Sorry, he might be able to confirm that he had seen such a report, but he CANNOT confirm what may or may not have been in them was accurate.