I couldn't even begin to guess and probably no one else could either. It's usually numbing meds and steroids. I wrote an article on what I read they put in it. It seems weird he would change what is used though especially since it doesn't appear it did you any good. When blocks stop working it means your pain has gone independent. I know that you can have independent pain on one side but not another. Usually what part has had it longest can go that way. Everyone is different and some stay smp longer than others. Everything always depends on the way our individual bodies work. It's no wonder there are no treatments for us. *sigh*

I'm sorry it didn't turn out so good for you.

Big Hugs,

Karen