I don't think that is true. Kevin Bozic at UCSF and James Herndon the program director at Harvard have MBAs and they are very active orthopaedic surgeons in academic settings. If anything, i think that would be a strong point on your application because several programs give their residents lectures on the business aspect of ortho and how to manage an ortho pracice when you graduate.
A piece of advice: As you progress through med school, you will hear a lot of things many of which are not true. Just work hard in whatever you are doing, have faith in your capabilities and you will be fine.

I agree with tornmeniscus. Beware of what people tell you. Whomever told you they'd look at you funny as a would-be-surgeon with an MBA is a dumbass. That's the most absurd thing I've ever heard. What...if you're a surgeon, you can't have other interests or skills?

PS My chairman has his MBA as well.

I am a resident with a MD/MBA degree. A MBA will actually make your application more attractive as most will be impressed that you did both at the same time. It is a definite advantage when you start looking for jobs academic or private.

There is absolutely no question that the MD/MBA will be an asset not only during your search for residency, but also later in your career.

I completed an MD/MBA program, as did two other residents in our program. While there are certain individuals who will question your motives and will give you a hard time, the vast majority of interviewers will understand the indispensable utility of an MBA throughout your career as a surgeon, and they'll respect your ambition. Further, it will serve as an interesting focus for discussion during the interview.

Please feel free to PM me to talk more.