i had wrist pain several years ago too.
i got a gel wrist pad.
now i have a natural (split key) keyboard. but the palm rest is hard plastic =( which does tend to cause some discomfort.
i also have a gel wrist pad for my mouse.
how i type: i sitting such that the armrests of the chair allow me to rest my elbows on them while maintaining a straight forearm wrist combination. this way, my elbows are supported, which means less strain on the arms, and the wrists are not in an awkward position.
some people type with their arms too close to their body, which is not good at all.
the best split keyboard would be one where the keys are situated FURTHER apart than they are now, allowing the arms to maintain that armrest position, as if not typing... that is, the forearms don't reach INSIDE to be in front of the body for typing.
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ergonomics helps folks... chair, keyboard, mouse... you should be able to use EVERYTHING without strain. the shape of the mouse location of the mouse should be such that it fits your hand, and you don't have to reach too far for it. the keyboard should be located as per the guides you have read...
you can't rig a tablet as a touch keyboard... the sensor field is fixed, you touch any part of the tablet, and the cursor moves to that spot of the screen.
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CTS is caused by pressure to the bottom of the wrist... where all those nerves and blood vessels go to and from your hand. if you examine the wrist, you can feel 2 bumps, which are bones, between is the tunnel. imagine someone constantly putting pressure on a pressure point, it's not good.
a gel wrist pad would eliminate much of the pressure on the tunnel.