The sciatica nerve can be impinged from a disc bulge in the lower back, joint misalignment in the lower back or degeneration which would create bone spurs. All of those conditions can be helped and/or corrected with chiropractic treatment. The sciatica nerve also has to travel through muscle around your glutes in order to get down your leg. Primarily, your piriformis muscle which sits at the top of your butt. So, if the spine itself looks fine on imaging, you could be suffering from ‘piriformis syndrome’ which is basically over active muscle impinging the nerve. That could still be chiropractic treatment or potentially physical therapy and/or massage therapy.
Hope this helps!
A chronic pain case of a few years might be better in a few weeks and an acute pain case of a few weeks may take several months to resolve. Regardless, chiropractic is a smart choice for treating sciatica.