I recently injured my TFCC while working out. It turns out it was slowly developing over a long time. After it tore, I realized it hurt while I used my normal mouse (Logitech G9x).

I switched to a trackball (M570) and still found that the angle of my wrist to be sub-optimal. I created this 3D printed part to provide an almost 90 degree angle for my wrist. To my surprise, it works very well. The only issue is that you need to provide an anti-slip surface to place the part on. I thought others would find this useful to either avoid injury or ease wrist pain.

I uploaded my SolidWorks file where you can edit the extrude-cut sketch (currently set to "XXX") to have your own initials on the support.