Will epidural steroid injection help a sciata nurve?

Yes. An epidural steroid injection is a minimally invasive procedure that delivers steroids via a needle directly into the epidural space to help reduce inflammation. It is effective for sciatic pain.
Might. Steroid will decrease the inflammation in the area of injection and if this is your problem causing the sciatica then will be very helpful.
Yes. However it will help the sciatic nerve at its source in the spine at the nerve root level.