Hi Mark
It is my understanding that Dr Bertagnoli in Germany has the most ADR experience in the world. Particularily dealing with difficult cases that no one else will attempt. I understand that financial and insurance issues are extremely important.
But this is your spine and you only get one and it has to last the rest of your life. It couldnt hurt at least to get an opinion from him and see what he says.
The other Mark can help you with this or you can contact Dr.B through his own website.
Go Freeo!
Michelle.