A minor point, but in the patient Q&A, get his contact info and the name of his MD.

The sprain is the obvious injury. It would be worth while to do a head to toe survey to be sure he didn't crack a rib, ding his head, etc. in the course of the trip and fall. Multiple injuries are more common with longer falls than the usual sprained ankle, but you want to be sure. Poeple who catch a fall on their outstretched hands often ding their wrists.