The
Evoluent mouse looks like it places your hand at an almost 90 degree angle, but it is more likely about 70 degrees. If you were to put your hands on the desk while seated, you would find that this is the angle that your hands will naturally rest in, or at least very close.
I used to use a Logitech scroll mouse, but found that after sitting at the desk all day my wrists were really taking a beating. With the typical generic mouse you are forced to rotate your hand too much, regardless of where you place your mouse.
This is the same problem that I am having with my scroll ball. I really like the
CST, but have to bend my hand too much, which after a while is just too problematic. I am currently working with a wedge that tilts the scroll ball to place the hand in a more natural position. A little different, but I will let you know how it works out.
Later........Ms Keyboard