EMPLOYEE WAS DRAGGING 1 1/4"" PLASTIC LINES. HE WAS GOING THROUGH A 30"" X 3"" MANDOOR WHEN THE CREW MEMBERS BEHIND HIM PUSHED ON THE LINE. HE FELL THROUGH THE DOOR LANDING ON HIS LEFT SHOULDER. ACCIDENT WAS NOT REPORTED UNTIL 9/17/04. FAILED DRUG TEST WHEN HE TRIED TO RETURN TO WORK.