Being that you will be taking physio, talk to them about the importance of continuing to sew, and what would be advisable. Even better, if you could get an occupational therapist involved, as s/he would be able to help figure out how the ergonomics for your particular issues.
Some stand up sewing and quite like it ...... probably a bit awkward at first, but we can all learn new tricks!
That being said ... before you go to the expense of a different set up, I would really recommend working with the trained professionals and be sure that what you change to is better for your overall condition, and not run the risk of making matters worse.