I am sorry that you have issues. I am not a Computer Wiz, but my experience with standard Mice & Trackballs are they make them to fit comfortably in the hand, so that thumb will always be a mile away from fingers. There are other type of corded mice that might work for you. This is a Trackball that fits on your index finger and you control pretty much everything else with your thumb. Some presentation devices might work for you also.