What do you think?

Yesterday while checking my line I had a big boar coon in a z-trap nothing unusual right? Well for the first time ever the coon was already dead..stiff as a board. The weird thing was that the coon had its paw in the trap and there was literally nothing but bone up to its chest. no blood/meat... nothing just bone. also on its back on each side of the spine were 4 marks where the fur was missing. They measured about 3 inches apart from each other. When I skinned him out i was hoping to find some evidence that he was crushed from a bite but once again nothing. so my question is what do you think happened and if it was a bite why didn't whatever did it eat him up? And how do you explain the leg? I have had animals in coil springs chew at their leg but nothing like this!!!