I was usually using a screwdriver to do this, but at some point that wasn't working. I had to use my hands. I told my dad to hold on, but he didn't hear me, and by thumb got smashed. I ended up losing most of my thumbnail from that accident. Even though some of my nail hadn't been lost, my body apparently thought all of it was, so when my thumbnail started growing back, I actually had a full thumbnail growing over a partial thumbnail. This pattern has continued to this day.