I have the same problem too and have had for years somedays I can't move standing straight up much less on the floor ugh. I have two folding tables from Costco's too and they are light weight enough that if hubby isn't here I can butt them up together myself to pin nice big work space. I also don't use masking tape when pulling my backing taut. Hubby bought me clamps that he found in a dollar bin at Alco's Store. He said you can get them at Harbor Freight too but not at a dollar a piece and that is how I stretch and clamp my backing to the tables nice and taut. Of course the all time best thing Hubby did was purchase me my "Lizzy" and although sometimes I revert back to pinning that is still my favorite way of quilting NO MORE PINNING!! He got me a Tin Lizzy in July I am sew lucky. Hope you get to feeling better soon but you really need to look into those tables to help you ease some pain and tension.