MX Vertical
Used by 4 peoplelogitech.com ↗

“Honourable mention: My Logitech MX Vertical mouse, it really helped me get rid of wrist pain.”
Torben Bökemeyer Interview, Illustrator, game artist · via Uses This 
“I started getting some wrist problems using regular mice a year or two ago, so I carry at Logitech MX Vertical around most of the time.”
James Goldie Interview, Data journalist · via Uses This