For me using the mouse caused me much pain. The fine positioning and operating the buttons were required conflicting muscle groups to cooperate. My solution is

For me using the mouse caused me much pain. The fine positioning and operating the buttons were required conflicting muscle groups to cooperate. My solution is to have a trackball for the right hand and a mouse with the optical window taped up for the left hand. Thus positioning and clicking / operating the wheel no longer require conflicting muscles to act. For me it was a revelation to actually slow down and watch out which micro-motion lead to which source of pain. Once I could sense the twitches, etc I could change my environment to better suit my physiology.