Hi,
I have been a long term sciatica sufferer, here are a few tips that I have based on my experience, I am now pain free(touch wood).
Firstly, I would recommend seeing a sports physiotherapist before going to see a chirporactor. After my experience, I will never see a chiropractor again. Dynamic, high impact movement on joints is not good for people with prolapsed disks!
My physio diagnosed the problem, asked me to focus on strengthening the core stability muscles (abs and back muscles) and also stretching.
I had a prolapsed disk which took time to heal but once that was cured I had sciatic pain caused by "tethering."
My physio recommended "Dr Ali's Back Book." I cannot recommend this publication enough, it saved me from an operation and the principles work. I had seen two doctors and a chiropractor(who made the situation worse). They both said I would need an operation. Well having read the above book and followed it's advice i can tell you I am pain free without any operation....
Do not focus on jsut your abs....stretching and stengthening of the lower back muscles are just as important.
In the end, my nerve finally realeased and has not come back.
Best of Luck...
Stewart