The short feature , which was preceded by a commercial for the final two episodes of '' The West Wing , '' looked at the difficulties faced by Barbaro 's trainer , Michael Matz , who survived a plane crash in Sioux City , Iowa , then led three children to safety ; Alex Solis , who broke his back in a track spill two years ago but rode Brother Derek on Saturday ; and Brother Derek 's trainer , Dan Hendricks , who was paralyzed in a motocross accident .