This is getting off topic but I hope that it helps the AI people who suffer from trigger finger as a side effect of the medication. But I will respond to help the golfer friend and anyone else who wants to understand better.

The doctor inserted a needle into the palm right below the finger. (This part is not a medical explanation—just an “in the ballpark” of my understanding.) Then he moved it up and down. Apparently, there is something around or near the sheath that the tendon passes through that makes it get hung up. So I don’t know if he was scraping inside the sheath or around. He did that until he felt a release. He did all the fingers that were making a clicking noise and had the potential to lock up. (He has a limit to how many he will do at the same time.) If this method hadn’t worked on the one that was completely frozen closed, then he would have scheduled surgery. To unlock that finger because it had been stuck many days over a holiday weekend (and urgent care would not touch it—normally my husband would be able to work it back open on his own, but not this time) he gave it a cortisone shot, numbed it, and then frighteningly pulled it open. This was done days prior to the doing the scraping. It seems to be a condition for my husband but so far, he hasn’t had any new triggers in 4 years. He left with a little soreness but no real pain. It was amazing.