I went to two different chiropractors prior to surgery. Both didn't help, in fact, they made my condition worse. I think they can help people with certain conditions, but they can't help everyone. Sometimes, sugery is the only option.
I don't have chronic back problems, but every so often, I do get some back stiffness. Have your try accupressure? Accupressure works for me (may not work for everyone). Used to do a lot of martial arts when I was younger, and accupressure works everytime when my back is stiff or pulled.
Getting back to the NSX seat, most comfortable OEM seat I ever sat in.