I have a curvature so that adds pressure points. My chair is about 5 years old so it’s due to be replaced.
Scoliosis. My sis had surgery for it. The open waterbed mattress would do you wonders and there’s a chair out now that can help. I forget what it’s called but you may know it by its description. It’s a woven semi-open material seat and back. Quality in those chairs is you get what you pay for.