I think you'd need an orthopedic or back doctor to interpret that test.

There is a Dr. Sarno, in NY who feels that some people channel anger/stress into their backs. He has a program to fix this without surgery. He has written several books, including Mind- Body Connection. I've seen the TV programs he was on!
http://en.wikipedia.org/wiki/John_E._Sarno

I have his book, and in it is an evaluation of testing accuracy. He says some people with horrible back Xrays/MRIs have no symptoms or few symptoms, and some people with more or less small changes can have large problems.

I tend to agree that most people can show spinal problems as they age.

I think another medical evaluation of your test may help.

(if you don't have PN anywhere except your feet, that MAY mean your back is the culprit. Most metabolic PNs are all over, hands etc. That is not to say it couldn't be metabolic and only in your feet, like maybe it has not progressed yet, but it is sort of a hint.)