citrus regrowth-discard or nurture?

[erikc]

I had bought a potted ippolito-blood orange and it was doing well for awhile repotted, new soil, fertiliser, sun, water, but it slowly died or so I thought but I gave it more seasol anyway before leaving a week ago. But on returning from overseas I noticed it has green shoots from the base. Is this root stock and worthless? Or is it potential regrowth? I think the main trunk looks still alive but the branches look dead (brittle, lifeless brown), I have not cut them to see if they are green inside but last week I assumed the tree was beyond saving.

It has a bend at the base but it is not clear to me that it is rootstock.