You have to tell the doctors about your new symptoms! Who ever or everybody of them! I believethey will listen, if one of them not, try another one! Do not do the operation without make sure that your symtoms in the legs really come from nerveroot from lumbal (yao1-zhui1) but a higher level. In that case, they are not "two symtoms but one". I think you might need to do MRI of the neck as well. However, go talk with your doctors since it is only they who can examin you. Dont hesitate.
I am not in the US so I am not sure how it works for you exactly. I would say go see Surgery Neutological !