Among other things.
Sister-in-law is a doctor and she said one of her first ever shifts in the OR(?) was someone with a degloving injury. They cut a "pocket" into your abdomen, stick your hand in there, and then cut your hand out when it heals. With a foot, they sew it to your ass. I don't recommend google image searching this btw...
Warning: Gross (Click to show)
As far as I understood, the skin on an appendage is totally removed in a degloving incident. Degloving is exactly what it sounds like, but with skin instead of a glove. A ring will pull skin off a finger if it gets caught on/in something, for example.
Hands and feet are too complicated for skin grafts, so they sew them into the body and skin eventually attaches to the appendage. They cut out the hand/foot and tada, the skin is now attached. It heals better on the abdomen/ass because there's a relative surplus of skin there? I'm not a doctor, but I think that's the gist. Pretty gross stuff.
I've worked with a guy with a similar injury. I used to build cabinets for a living. A former coworker of mine tattooed a wedding band on his finger because it's kinda dumb to wear a ring and run shit through a tablesaw all day.
I put a 3" nail through my hand once. Don't work with my hands anymore.