I had back surgery in 2010 i had my L5 disc remove and replace with artifical and screws. before i had surgery the nerve in my leg up to my back was hurting real bad and my feet was norm. but after surgery for 2 years my feet still norm and i am still having back pains very bad. i use can walk for exercise but now i can't walk a mile if i do my whole legs and feet go norm i have to stop shake my leg to make the feeling come back to it. what must i do?