My WIP notes on an ergonomic mouse. The 'ol right wrist and forearm is acting up, so the Apple Trackpad that I've been flicking my fingers over isn't cutting it. I'm always findng myself with my wrist cocked back, hovering over the trackpad. There's a lot of tightness in my right forearm and wrist, and I've got that "hot" tennis-elbow feeling, along with some weakness in my grip.

general info: should you switch to a trackball?

Wirecutter says:

In a survey published by trackball maker Kensington, respondents listed their top three reasons for switching to a trackball:

I'm looking for #2 most primary. Space is not an issue, and I can deal with a lack of speed and accuracy if it's better for the wrists.

Trackballs can be useful for people with a repetitive strain injury in their shoulder or wrist because using one of these devices requires different muscles than using a mouse. Ergonomicist Alan Hedge pointed out to us that a trackball is most useful if it helps you keep your hand in the correct position: "The key to safely using either a trackball (or a mouse) is to operate the device with the hand in a neutral posture (this means the hand is straight and level, not bent up, down, left or right, or twisted)." This neutral position is easier to maintain with a trackball because unlike a mouse, a trackball doesn’t move. Hedge continued, “Rather than extending the hand upwards to allow the fingers to move the ball, it is better to use flat fingers or the palm of the hand to rotate the ball.”

I have wondered whether the wrist should be in it's "natural" position, rather than neutral: if I simply hang my arms down at my sides, they are not paralell with my body line, which the "neutral" mouse seems to encourage. But Alan doesn't think this is a problem.

Trackballs come in two variations: finger-operated and thumb-operated. Finger-operated trackballs place the ball in the center, so you can use them right- or left-handed. And they often have a larger ball, which makes it easier to fling the cursor across a larger space, such as on a 4K monitor or across multiple monitors. Thumb-operated models look more like traditional mice but typically have a trackball on the left side, so they’re comfortable only for people who mouse right-handed (which is almost everyone). Since thumb-operated trackballs look and feel more like a traditional mouse, with a scroll wheel set between two top buttons, they’re easier to get the hang of. But their smaller ball requires more effort to move the cursor across the screen, so they’re better suited for use on single monitors or low-resolution displays.

I'm liking the idea of left-handed mousing. Why not spread the wear out over two hands? And probably the finger-operated version is best, since I'm working with three screens. And this looks juicy:

Since trackballs often have four (or more) buttons, they’re easier to customize than trackpads, which rely on gestures for basic actions.

Haven't gotten into mouse customization yet!

And Alan claims that the flat, finger-operated balls are safer:

Thumb-operated trackballs don’t work for everyone. “Overuse of the thumb can result in de Quervain’s tenosynovitis, where extending the thumb becomes a painful movement,” Hedge told us. "A finger-operated trackball allows for the finger to be flat and for it to slide back and forth over the ball to move the ball, which will reduce injury risk." That notion tracks with our testing experience: We found that finger-operated trackballs encouraged better ergonomics—full arm movements and neutral wrist posture—compared with thumb-operated models. We’ve also seen complaints online about thumb pain from using thumb-operated trackballs, but we didn't experience any pain in our testing. And many people have used thumb-operated trackballs for years or even decades with no problems.

Oh, here's a nice surprise:

We found trackballs more precise than trackpads and more usable for design work or anything else that required accuracy.

I thought I'd be giving up accuracy over the trackpad.

Wirecutter's "Best Trackballs" article

Finger-operated trackballs with center-mounted balls work for both right- and left-handed people and encourage better wrist posture, while thumb-operated trackballs are more similar to traditional mice and therefore easier to get the hang of. (For more information, see Should you switch to a trackball? below.)

Wirecutter says that the Kensington Expert Mouse Wireless Trackball is best, noting:

The Kensington Expert Mouse Wireless Trackball is the best finger-operated trackball because:

logs

2022-11-09

A few thoughts:

  1. when I use the trackpad, my right arm is in front of me, and I have issues with that shoulder: it sits more forward that the left. putting it again and again in that position is probably not ideal!
  2. use the space bar or vim browser plugin to navigate web pages (using an external mouse encourages this because I don't want to move my arm from the keyboard to the mouse)