On June 12, I injured my left thumb getting a lawnmower reassembled. The friend who had helped me transport the mower back from the repair shop, didn't see that my thumb was in between the handle bar when he yanked it into position. My thumb got smashed. It hurt like hell. I was lucky it wasn't worse.
Every day since I've been massaging and stretching it trying to get it to feel the same as my right thumb. Progress has been slow, but today it actually feels noticeably better. One thing I've done recently is to really stretch it harder than before and force myself to go through whatever pain there is. So that's it - seven months of daily massaging and stretching to try and undo a split second. Be careful doing yard work, and wear gloves!