2003 TOYOTA PRIUS WAS PROCEEDING WEST ON I-40 NEAR KNOXVILLE, TN WHEN THE TREAD SEPARATED FROM THE LEFT REAR TIRE AND WRAPPED ITSELF AROUND THE AXLE CAUSING THE DRIVER TO LOSE CONTROL. THE CAR VEERED TO THE LEFT THEN TO THE RIGHT, HIT A GUARDRAIL AND THEN HIT A SEMI HEAD-ON. THE VEHICLE WAS TOTALED, THE DRIVER SURVIVED WITH A CONCUSSION AND A HEAD WOUND. *TR