EE WAS STANDING ON FRT BUMPER OF PICKUP MANTRIP CHECKING A BACK UP ALARM WIRE. AS HE STEPPED OFFTHE BUMPER (APPROX 32"" ABOVE GROUND LEVEL) HIS RIGHT FOOT SLIPPED FORWARD ON THE GRAVEL CAUSING EE TO FALL BACKWARDS EXTENDING HIS RIGHT ARM TO BRACE THE FALL. EE STARTED MISSING WORK 8/29/01