Hi ~ A graft is where they either take bone from your hip (very painful) or from a cadaver and fuse it to your spine to take care of the problem.
A "cage" is where they put this "cage-like" thingy between the vertebra to take the place of the disc. They have to remove all of the disc to do this. Then the cage retains the space between the vertebra.
I'm sorry that I'm not familiar with the "elite plate." Hopefully someone else can help you with that.
Best of luck! Take care & God bless. Hugs, Lee