Forensic Pathology

by Ripley

In a story I'm writing someone is killed by a professional assassin. Their neck is snapped manually and then the body is thrown down a staircase to make the broken neck look like the result of an accidental fall.

When the autopsy is done is there any way the pathologist can show that it was murder i.e a particular bone in the neck snapped in a way only possible by snapping the neck manually and not the result of a fall?

Any help greatly appreciated.