Interstate Utility Services, Inc

After a drill rig was unloaded from a trailer, the injured employee backed the semi tractor to the empty trailer (combo unit). He exited the cab and moved to the left side of the combo unit where the airlines and trailer controls are located. He secured a pin between the gooseneck and the trailer deck. He was connecting the airline from the tractor to the trailer when the combo unit began rolling backward. The employee was dragged beneath the trailer for approximately 25 feet before the combo unit collided with a traffic control vehicle and stopped. The employee was hospitalized with fractures to his pelvis and left tibia and fibula. He also sustained lacerations and abrasions along his left buttocks and thigh.