Death from broken neck

Question: I hope you’re the right expert to answer this.  I’m writing a mystery novel in which a character dies from falling into an excavation.  The trench is about 10 ft deep and 4 ft wide, and the character is a healthy young man, thin, 5 ft 11 in tall.  He’s standing near the edge of the trench, takes a step backwards, goes over the edge, hits his head on the way down, then lands in such a way that his neck is broken and he dies instantly.  Is this possible?  And, assuming that his body is not found until it’s mostly skeletonized, what evidence would there be of how he died?  (I need him to have a head injury too so there will be some ambiguity about whether it was an accident or a murder.)

Thanks so much!
Answer: Wow.  Didn’t expect that one.  I’ll only answer if the good guy is a chiropractor: )

It is ENTIRELY POSSIBLE to die within a 10 foot fall, just look at Liam Neeson’s wife.  The brain is pretty close to the consistency of yogurt. Especially if the was a sharp object (rock) on the side to focus the force.  Understand that if the damage occurs to the neck, say above C4, it can essentially kill/ cut the phrenic nerve, which powers the diaphragm (the muscle that moves your lungs).   There’s no reason that the head trauma couldn’t occur at the same, or that he hits an outsticking log/ branch which traumatizes the head, then flips him down onto something that unfortunately broke the poor fella’s neck.  (If his body’s going south and his head’s facing north, that’s a good indication the neck was involved). Maybe a better judge of that trauma would be a fractured neck, like at C2, where the dens (peg of C2) is… it’s called a hangman’s fracture, anyway. That would show up on pretty fossilized remains, and would definitely point to that as a cause of death, and just sounds cool.

Hadn’t planned on answering this type of question, hope my answer helped.