Can be dificiency
I have gone through your query.
Main cause of numbness
in feet is compression of nerve
in the back. Since your back x-rays didn't show any sign of compression, it can be ruled out.
Other cause is deficiency of Vitamin B12
and D3 along with electrolyte imbalance
.There can be poor conduction of nerve impulse.
I suggest you to go for blood test
for levels of B12, D3, calcium, sodium and potassium along with nerve conduction test. Consult an Internal medicine specialist for clinical examinations also.
Hope I have answered you. You can close the discussion and rate the answer, if you don't have further query.
Wish you good health
Dr. Gaurav Katiyar
For further queries you can contact me directly on http://bit.ly/DrGaurav