posture when on the 'puter

That's a good point Jane. My monitor is too low, never thought of that.

Is your monitor at eye level or are you having to crouch down a little to see it? At work we were all shown how to raise our monitors to a height that's easy to see.
You could put it on a pile of old telephone directories?

Same here Willow now I have a pair of gloves with the end of the fingers cut off.

Get a proper adjustable desk chair. If you have RSI, you can get specially designed and shaped keyboards and mice which are much more comfortable to use than the standard keyboard and mouse. DH has some problems with his arm and swears by them.

I've sat in front of a computer for many years and have found that if I'm not squarely in front of the main monitor I'm using I end up with a bad neck and shoulders. I also have to have the chair at the right height and consciously make myself sit back off the edge of it but I couldn't use an ordinary chair so perhaps you need to invest in a proper one. I'm right handed so my right hand is always cold when I've been using the mouse for long periods.

Charleyg I thought you would have! I've often been surprised, though, by people who have said that they're right/left-handed and wouldn't be able to use the other hand, so they never even tried!

I haven’t used a computer for years I went to a laptop and now don’t use that at all I only use my iPad which I can use sitting, lying standing or whatever

Squiffy yes I have, but I have run out of hands. I am very ambidextrous. I really need to stop for around a week because I had swopped to my right but it was becoming painful also hence the move back to my left.

Charleyg Asking the obvious here, but have you tried swapping hands? I’m left-handed, too, but now use my right. Like many l-handers, I’m fairly ambidexterous, so perhaps you are as well.

Fennel Me too!! I invested in a wedge shaped cushion and have found that it really helps. It makes me sit up straighter because of the way it tilts.

I do also and ended up buying a proper computer chair which does help but like me, you probably spend too much time in front of it. Have you tried adding a pillow or a cushion?

My main problem is tenosynovitis left hand using my mouse- again too much!