Consultant ortho. In 100 meter walk!

As per told by you , that you have had polio affliction, it's the ailment of muscular system...as narrated by you since the infliction was mild the functional restrictions must not be felt all these while..current pain in back and inability to walk even for 100 mtrs could be due to 1.muscle loss due to polio and resultant changes in alignment and posture while walking may put undue stress on structures of back, so may cause pain Or 2. It could be totally unrelated to polio Information provided by you is not adequate , i recommend a thorough evaluation of musculature of back and spinal alignment by a good physiotherapist will definitely help you come to conclusion as to what's the cause of pain and what solution could be useful

meet a physiotherapist with spinal x-rays..

please take a professional opinion and thorough check up before starting any treatment