FrankG,
Looks like UHC may be covering this now. Not sure about state to state.
https://www.unitedhealthcareonline.c..._the_Spine.htm
I was looking at having this done about a year ago and got denied once by UHC. I had been doing much better without surgery and then this past weekend while working on putting air conditioner in my camper started feeling quite a bit of pain. Hopefully it's pretty temporary, but started looking around to find out of artificial disc is being approved by UHC now and ran across the above link.