I'm sure this is possible/has happened, but I would think it to be a relatively uncommon event, seeing as most ortho interviews occur during Dec/Jan and (IMO) that would be too late to be doing an away in the specialty you wish to match.
Having said that, I don't think it would be a big deal - everyone has to interview, and if there is no way around a certain date that is during another ortho away, so be it.