A small anecdote ...
For a long time, many months, I was pressing the middle mouse button (the wheel) with the last joint on my index finger. I did not realise I was doing this, it just happened that that part of my finger was closest to the apex of the mouse wheel when I wanted to click it.
I middle click to open web pages in a new tab, and that happens on GH a lot. A very lot
Then that joint on my index finger became really sore. So sore that I could hardly touch anything with the end of that finger.
For a week or two I discovered so many thing that I did with my index finger, from opening cupboards and drawers, grabbing a box to life or move it, middle clicking (obviously), lifting the lid of rubbish bins ... the list went on.
I could not do any of those without a sharp stabbing pain from that joint.
Careful inspection and gentle rubbing of the area did not reveal any discolouration or swelling, so I resolved to try not to use that finger much, if at all, for a while and see if it got better.
It was pretty much at that point that I discovered how I used to middle click.
After a month or two, I stopped noticing any discomfort in that joint. Now I can do everything I used to do, including middle clicking with that joint, without any discomfort.
It seems to me that repeatedly (hundreds of times a day) middle clicking on that particular spot caused me an injury. I don't know where it would have gone if I hadn't found out what I was doing.
I still use the same mouses, keyboards and so on, but with that small change in habit, my finger is again happy.