Back pain with leg proble. I do now?

Back pain started in January 2016 after doing squats in gym,consulted in aiims, neurosurgeon done traction as well, also did exercises but no relief till now. Currently i have pain from lower to middle back region of spine with stiffness in back including sensations in legs, left leg predominantly. Bending forward causes feeling of pain in spine. MRI done in may shows no nerve involvement with a mild disc dessication L5 S1 then why problem persists in legs; none of the doctors could explain it to me. Already taken steroids, nsaid, muscle relaxants, pregablin, gabapentin, neurokind etc. In present i am going to a magnetic therapist Mr. Amrik singh, attended 3 sessions till today but no sign of relief. What should I do now? Please suggest me every possible whether it is biopsy or some kind of blood tests to go into the root of the problem.