Had a right total knee replacement 4 1/2 years ago. 6 months after surgery complained to ortho that right foot is still numb, 3 year later I brought it up again, I have had 2 EMG-normal, seen podiatry and neurology and they can not figure out what is going on-all have reviewed my records for surgery and everything appears to be normal-this numbness feels like walking on a gel pad at times, to not feeling getting blisters on the bottom of the foot. Was told to keep buying shoes until I find a pair that is comfortable. Only thing comfortable are my Birkenstocks which I cant wear in the winter. Any suggestions?