Robin,
Here are the facts, based on the FEHB letter I posted. If your insurance is held through the FEHB program, they cannot classify anything that has been FDA approved as "experimental" or "investigational." The reason for this is because OPM wants consistency in applying the "experimental and investigational" label for all employees, regardless of the plan.
FEHB carriers can still use the "not medically necessary" nonsense but IF you meet the restrictions set out for disk replacement by the FDA (one level, L4-S1 area only, etc) an FEHB carrier, by law, cannot claim that the device is investigational.
For example, take a look at
Independence Blue Cross in Philadelphia.
Click on the link for Medical Policy Bulletins (accept the terms), then click on Policy by Title, then find the Artificial Intervertebral Disc bulletin. If you read this, you see that BC/Philadelphia classifies the Charite disk as experimental EXCEPT for members under the FEHB plan, in which case it's covered.
I can also understand your frustration with the Dr office. They get so many of us, I suspect, and they don't have time to learn all the rules for every insurance flavor that's out there. Nobody cares more about this than you do, so read your plan, make sure you understand the appeal process,
and don't depend on the dr office.
Hope this helps,
-stan