A EMICO 975 MATERIAL HAULER IN MAIN HAULAGEWAY, HIT SOMETHING IN ROADWAY CAUSING INDIVIDUAL TO BOUNCE OUT OF SEAT HITTING HEAD AGAINST MINE ROOF. INDIVIDUAL CONTINUED TO HAVE PAIN IN NECK AND SAW DOCTOR ON 6/7/02. ON 6/11/02 SAW DOCTOR AGAIN AND WAS HELD OFF WORK FOR STEROID TREATMENT OF NECK; QUESTION OF DISC DAMAGE.