Logitech MX ERGO - Page 29

Five key muscles are used while moving a mouse or a
trackball, and can be involved in potential injuries (e.g.
epicondylitis).
The less they work, the more relaxed and comfortable the
user is.
Upper trapezius
Extensor
carpi
Flexor
carpi
ulnaris
Thumb
abductor
Thumb
adductor