The picture is a press shot of Post Malone with YouTuber Garand Thumb (real name Michael Jones), a U.S. Air Force Veteran who has been posting videos on gun and military culture since May 2006.

Garand Thumb. It’s often said that there are two types of Garand shooters, those who have gotten M1 thumb (a.k.a Garand thumb) and those who will. But what is this so-called injury, ...