I have generally found that Doctors, for all their terrific knowledge of medicines are less clued-up about backs (and nutrition). It is perfectly logical that you may still have residual tension in your feet which would, of course, spread upwards. I found great relief from a fairly new Australian therapy called BOWEN THERAPY. The therapist 'rolls' various muscles to instruct the brain that these are to be released in a particular order. I had an old injury to my knee which gradually spread until I suffered a prolapsed disc - muscle imbalance is the cause! It is incredible how one can be limping but hardly notice it. For ten years I had treatment on my left knee which would soon become so painful that I would have to stop even in the centre of town and just stand waiting for relief. Then, one day I noticed that because of my original injury which had cause stiffness on one side of my body I was moving differently on each leg. When I moved my right leg it moved normally but when I moved my left the movement came from the whole of my left side - I was twisting my knee every time I moved. By simply loosening my pelvis, consciously moving from each buttock, hey presto, no pain! So, apart from needing the Bowen Therapy I also needed to observe movement and tension!