re: What is the most gruesome injury you have ever witnessed?

On a construction site. Driver was transporting pile driving hammer to site when car traveling opposite way swerved into his lane to make a wide u-turn. Truck driver slammed on breaks which successfully stopped truck. Pile hammer continued moving forward, snapping chains used to hold it down and allowing pile hammer to essentially move completely through cab of truck. Was like a scene out of a horror movie. Image stuck in my head years later.