I had a bad back and got a HAG H09 with the medium back but a long seat tube. I worked at home for several years in it. Now retired if my back hurts, sitting in it is the best remedy! Works for me.
Also set up your workplace correctly. First adjust chair so that feet are lightly on the floor. Bend your arms by your sides at 90deg. Where your hands are there should be you desk/keyboard. I have 2 bricks under each leg of my desk to make that work. Then your monitor at eye level - I have a laptop screen lower but a second monitor as main work place at eye level. Works for me.
Also set up your workplace correctly. First adjust chair so that feet are lightly on the floor. Bend your arms by your sides at 90deg. Where your hands are there should be you desk/keyboard. I have 2 bricks under each leg of my desk to make that work. Then your monitor at eye level - I have a laptop screen lower but a second monitor as main work place at eye level. Works for me.