Hoo boy. ABC news has lost all credibility in my eyes - and especially that bozo MD who acts as their 'medical consultant'.
They are describing a case of atlanto-occipital dissociation. This is where the first cervical vertebra dislocates from attachment to the skull. In other words, it's a cervical spine fracture: a far cry from having one's head ripped off one's body. It's an unstable fracture, so if you have the misfortune of having your cervical spine shift out of alignment, you can suffer immediate severe spinal cord injury, causing you to lose all respiratory function because the injury is so high (above C3). Usually this is not identified (why is the patient coding?!?) until post mortem examination. But, as in the case of this kid, if you are fortunate enough to escape spinal cord injury during the mechanism and are then transported with careful spinal precations, you've got a shot at repair and survival.
Jeez, they make it sound like the kids head was dangling down backward between his shoulder blades, attached only by his amazingly resilient spinal cord.
A real-life Nearly Headless Nick! 
(149 days until the release of Harry Potter and the Order of the Phoenix )
Mary you stole my thunder…!!! 