Has anyone ever been severely decapitated?

not severely. Slightly, maybe.

It was just her wig. I believe her head remained attached.

http://www.snopes.com/movies/actors/jayne.htm

"...Although Mansfield's actual mode of death was gruesome, she was not beheaded. According to the police report on the accident, "the upper portion of this white female's head was severed." Her death certificate notes a "crushed skull with avulsion (forcible separation or detachment) of cranium and brain." One thinks of a beheading as the neck's being sliced through, causing the head to be separated from the body, but that is clearly not what happened here. Scalping is perhaps a closer description of Mansfield's fate, but even that word does not accurately reflect the cranial trauma she suffered, because scalping victims at least retain an intact skull. The Angel of Death did not afford Mansfield this luxury: Her skull was cracked or sliced open, and a sizeable piece of it was carried away.

As gruesome as this mode of death was, it at least had the benefit of being quick. Mansfield probably never felt what happened to her, and because of the sharply reduced visibility conditions on the road that night, she likely had only an instant of "We're going to crash!" shock to cope with before the impact.

Kenneth Anger's 1975 Hollywood Babylon contains a controversial photo of the wrecked Electra which shows Mansfield's dead dog lying beside the car, but the item in the shot that arouses discussion is what appears to be a blonde wig. Was it truly a wig, or was it the top part of Mansfield's head?..."

and I wouldn't recommend it.

Khash.

chop off their heads with a hatchet and let them run through the yards untill they dropped dead. Boy those things ran around a long time.

I have been decapitated and I don't think it is funny to put us down that have! I am hitting alert on this thread and putting you on ignore!
I am sick of all these threads putting us decapitation victims down.

rather than blaming others for loses.

I have you on ignore. Remember?
P.S. It really wasn't my fault. Someone didn't yell "Duck" as we went under the bridge.

Take a deep breath. Oh wait, you can't.