EE WAS STANDING ON AN UPRIGHT HAUL TRUCK HOOKING UP CABLES TO PREPARE IT TO BE MOVED OTHER MACHINERY BECAUSE IT WAS STUCK. ONE OF THE OTHER PIECES OF MACHINERY JARRED THE HAUL TRUCK, CAUSING E E TO NEARLY LOSE HIS BLANCE. THE SUDDEN JARRING MOTION CAUSED HIM TO BE JOLTED AROUND AND THUS CAUSED A LOW BACK INJURY.