Based on the information you provided about your wife, you may want to consider a Mirra Chair. While Aeron and our Embody Chairs are also great choices for back problems, I think you will find that Mirra will be best suited for your wife's situation. Mirra's seat has a waterfall edge, which allows for adjusting the seat pan to fit your body. It is designed so the back of your legs do not hit the front of the seat edge, which can sometimes be a problem.
When leaning back, Mirra's back support flows with your body, which is ideal for people who have back issues. It will allow your wife to recline in her seat without putting added stress on her back. The arm rests also allow you to adjust them vertically, horizontally and pivot inward and outward. This will provide flexible support for her arms while sewing. We would recommend choosing a Mirra with the following options:
- Tilt Limiter and Seat Angle - this will allow you to adjust the tilt range and either a horizontal or 4 degree forward seat angle
- Adjustable Arms - to adjust the arms for flexibility while sewing
The specific configuration we would recommend is the following:
http://store.hermanmiller.com/store...You may also be interested in choosing this configuration with an upholstered back for added warmth while your wife is sewing.
If you would like to see the Mirra Chair in person, feel free to visit a Herman Miller authorized retailer in your area. Here is a list of our authorized retailers:
http://www.hermanmiller.com/Store/S...If you have any additional questions, please feel free to contact Herman Miller Customer Care at 888-798-0202.