No pad, no backing plate. I cant see how it could have fallen out the way the caliper and bracket are set up. The piston was out all the way just touching the rotor, Only thing I can think of is maybe the backing plate cracked and fell out? Like I said the rotor wasnt chewed up or even scratched.
Only injury I suffered was a strained sphincter , from when I saw that truck up in the air, rolling over towards me.
I have an Autopower rollbar in my car, but that still would have hurt!