They call this elbow dislocation "Nursemaid's elbow". I guess because nursemaids were always dragging about their uncooperative tots. The doctor popped her elbow back in place and she screamed for a while afterward. We came home and she still wasn't using her arm. So the next morning we went back into the ER to have it checked again. The doctor tried doing the pop-it-back-in maneuver a couple of more times and then wrapped it up in a splint and sent us home with a number to call if it didn't improve. After being home for about an hour she demanded that I take the splint off and she gradually started using her arm again.
It's still tender, but it's much much better. Now, if only she would stop dangling when we hold her hand. I have to make sure that I only hold her right hand and that I let her drop when she buckles her legs.