I Have Seen A DPM In Aug 2015, Been Diagnosed

I have seen a DPM in Aug 2015, been diagnosed of heel spur of my right leg. I got orthotic insole and no pain afterward. Jan 2016 I start to feel numb on same leg, first it is numbed from the heel up to the foreleg, some days it radiated up to thigh or buttock. I went back to see DPM again, he said that I have a problem with the back, not the foot anymore. I don't take any medicine for pain now. Symptom subsides when I sit down, and pain increases when I stand up long time.