When I was your age I also wanted to be an orthopedic surgeon. You should be thinking "what will make me the best at my career" rather than "what will give me the best chances of getting into med school."
Why don't you ignore everyone and go talk to some orthopedic surgeons about what would give you the best background? I did, and I chose mechanical engineering and biology. I've had every advantage you can imagine over my peers in med school, especially when it comes to research, attending respect, and actual future ability to improve the field.
What has always irked me is that pre-meds, (and pre-pre-meds) think that getting into med school is this huge accomplishment and that's where all their focus lies. Very few actually think about "huh, I wonder what residency is like" or "what is the life of a physician?" You have no idea what you're getting into, and it becomes apparent during the interview process.
Med school is not an accomplishment - it's just a formalized way to learn how to prepare yourself for residency. Lots of idiots get in from every type of background. Immerse yourself, and learn about all the bad and the good.