don't worry about it. the papers will look good no matter what they are in. shows you are interested in research. of the pubs/posters on my CV: three are general surgery, only one is ortho. This has not been a problem at. I have been asked: "were you considering gen surg?" a few times. Just be honest and say originally thought you wanted to do neuro surg and then later discovered that ortho is awesome and couldn't see yourself doing anything more rewarding... you could even mention this in your personal statement. in my PS, i wrote how i didn't decided to do ortho until midway through my third year.
now that you have decided though, get at least one pub/poster in ortho. get involved in something now! if would be best to have at least something ortho on your CV.