I've been using the ErgoDox and
my personal variations on that design for about 18 months.
Just recently I've discovered pain in the fleshy part of my thumbs, which I'm now convinced is caused by this design coupled with my current key layout. I'm no good with anatomy but from looking at google images, I think the pain is in my abductor pollicis brevis muscle.
Has anyone else had trouble with overworked thumbs using the 'Dox or one of the now numerous variations?
I think in my case I've 'improved' the ergodox too much! Instead of the thumb clusters being too far away, they're now too close. Specifically, my placement of the space keys on the bottom row of an ergodox (which I did because the ergodox thumb cluster was too far away) has lead to my continually curving my thumb inward to press both space and FN.
I'm
hoping that a remapping of keys to put space where my current backspace/enter keys are and some related shuffling will alleviate the problem. At least for long enough to build a new board.
This begs the question, if we ignore the issue of potentially overlapping other keys, what is the
ideal placement of the primary thumb key, assuming a flat keyboard? I say flat meaning I'm not dealing with contoured curved keyboards, the thumb keys here are in a flat plane with the rest of the keys.
Paying extra attention to my thumbs because of this issue, I've noticed that now (and perhaps before too?) my left and right thumb 'resting' spots are actually different. At rest, my left thumb sits comfortably on the space/fn key of ZusDox1 and ZusDox2. My right thumb however rests most comfortably just to the side of that key, between it an enter.
There are a few other minor issues with this design so I'm willing to make version 3, but I'd like to take some of the guess work out of thumb key placement. I'm not sure how to go about doing that though. Hopefully someone here (Jacobolus?) can give me a pointer or two about the workings of thumbs so that I can determine the best spot without going through multiple iterations of fully build keyboards.
I'm also now looking once again into multi-part designs which will let me put the thumb in a different plane, however given that the pain seems to have been triggered by the inward-curling of my thumb, I'm not totally convinced that pressing keys with that motion is going to help!