[Gertm]

You just described my exact work setup.

A couple more suggestions:

- Try to get your screen at eye level. If you can avoid having to look down all the time, you'll put much less strain on your back.

- Your forearm and upper arm should be making an angle close to 90 degrees.

- A little footbench or something you can lean on with your feet, so you don't have your legs dangling or being folded up underneath your chair.