I found a chair that is totally adjustable, including that the seat can be tipped forward just very slightly and locked. That sounds a but strange, but what it does is take pressure off the upper leg area, improving circulation. I learned about this from a doctor-quilter guest on Simply Quilts. When I went looking for a new chair, I looked for one that could be adjusted in every way. I also wanted a leather chair because they are so easy to keep clean. My office chair, which is very comfy, is fabric and everything sticks to it especially pet hair, and it doesn't give up that stuff to the vacuum either!