Originally Posted by Fuzzzy

I assume there is a very good, but unstated, reason why the doc wants to fix C3/C4 rather than C6/C7 which seems to be the bigger issue for you right now?

As Kzonts suggested, I would get a second opinion--from someone totally unassociated with the first doc. Hopefully that will give you enough reliable information to make an informed decision of the best path to take under the circumstances.

A dilemma among good choices is far easier to resolve than one among only undesirable alternatives. It seems that you are faced with the latter. Good luck and let us know how it goes.