2002 FORD WINDSTAR STRUCK BROADSIDE BY A OLD CIERA ON RIGHT SIDE. RIGHT SIDE OF CAR WAS LIFTED UP, THEN CAR CAME BACK DOWN. EITHER COLLISION OR NEAR-OVERTURNING POPPED THE LEFT CENTER SEAT (CAPTAIN STYLE SEAT) LOOSE FROM FLOOR. INJURIES IN CRASH WERE NOT RELATED TO SEAT FAILURE. SEAT WAS NOT OCCUPIED.