To reduce overuse of my (left) hand, I systematically started to introduce rules and focus of attention. Rarely is it necessary to find some other product that I can use.
Computer mice are known to pose a possible risk for overuse and carpal tunnel syndrome. So finding good mice is one thing, finding good keyboards a second thing - but putting the hosed arm to good use the best.
Cherry sells a "compact keyboard" with a built-in trackpad on the right side. Turns out that this really activates the damaged arm because as I already know from my cell phone and tablet, the stump is good for taps, slides and all things touchpad and trackpad.
Buy Cherry compact keyboard
The keyboard is neither hard to obtain nor hard to connect.
- AMAZON.COM Cherry G80-11900 Series Compact Keyboard. G80 TOUCHBOARD 104KEY PS2 BLK 16IN KEYB TCHPAD US MX GOLD KEYSW PP-KB. PS/2 - QWERTY - 104 Keys - Black - English (US)
- AMAZON.DE Cherry G80-11900 Tastatur Touchpad USB 2.0 deutsch
Video demo of compact keyboard usage
As you can see the accessibility of trackpad function is rather smooth.