Originally Posted by Infinity9999x
Not necessarily. You'd just had to be able to make a clean cut through the cartilage that connects his vertibrae. That's actually something the comics always got wrong, when it depicted larger stronger characters trying to rip Wolverine apart. His bones can't break, but the connective tissue holding them together sure would. Ultimate Wolverine vs Hulk actually got that instance right.
Now, if they added something saying that they also interwove very smalls strands of adamantium with his connective tissue, then yeah, he wouldn't be able to get ripped apart/cut apart or any thing like that.
Wasn't decapitation in the old Xavier Portocols? I am pretty sure it was. Seperate his head from the spine and then keep the two parts away from each other so he couldn't reattach.