I was diagnosed with tendonitis in my right thumb in November 2019. Since then I have been using a brace on and off to handle the flair ups of pain. When I was wearing it at work I noticed my computer mouse was next to impossible to actually use, and I ended up learning all the keyboard functions I could. To fix the mouse problem I found this, and ever since I have purchased a second one for my home office too. If you are like me and live on the computer all day long during the week, this is a great investment to make. There are other great brands too!