Gratefully no.
I have heard that the dyno discs work as well as those strong mesh backs for chairs. I've heard they can be purchased for as much a $10ea, 3 for $10 or .99 each at the Dollar Store, altho I don't know if all are of the same quality.
hope you find a good long term solution to your aching back while sewing.
warm quilt hugs, sue in CA