Moving to an endurance frame, helped to get a little pressure off my wrists and keep my neck less bent. It does put more pressure on my lower back but it is manageable. No frame geometry is going to treat sciatica. That needs to happen off the bike. Yoga Flow has really helped some sciatica I was experiencing. My wife and I did a lot of Amazon Prime Yoga vids during lockdown. I am definitely feeling the benefits on the bike and in my other hobbies.