There are probably multiple different causes for RSI in programmers, but for me, a regular keyboard is fine. Even my slouch is fine. I type with my elbows on the table and it's fine. It's the mouse that killed me. A handful of years after graduating from college, I thought my programming career was over because the pain in my neck and shoulders was so bad I couldn't type. I went to a bunch of doctors, neurologists, p…
It was the mouse for me as well. It started to cause sharp pain on the underside of my right elbow. The problem seemed to be the numeric pad on the right side of the keyboard, which pushes the mouse slightly further away from my body, stretching my arm slightly further out. The solution was to switch my mouse to the left side, where it could be slightly closer to my body. It took a few months of getting used to, but…
A concerted programme of golfer's elbow exercises and creating a split keyboard as described have dealt with the pain.
I am now using a Slimblade trackball and not getting on with it: it causes different pain and 3 months in I am still not accurate.