A "pulled elbow" (sometimes called a nursemaid's elbow) is subluxation of the radial head at the elbow (or, if you are being very technical, subluxation of the annular ligament). It usually occurs in kids aged 1-4.

The name pulled elbow literally describes the mechanism of injury in most cases - typically it's a child who is about to run onto a road or fall or something and someone grabs their hand and pulls, or when you are lifting a child up by the hands - and POP you've got a subluxation that needs to be reduced!

There are two main techniques to reducing a subluxed radial head. Basically in one you pronate the hand and in the other you supinate it and then in both you then flex the arm. Both are painful for the child.