I have gone through your query.
Pain with burning sensation in leg is suggestive of nerve
compression. Since you have mentioned you have some issues with L4,L5 and S1, it is most probably compressing the nerve coming out from there. There are chances of stenosis too.
I advise you to consult a neurologist
for clinical examination and MRI
In the meantime you can take NSAID
and Vit B12 for pain and can try lumbar support belt.
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