EA-6B1,
To answer your question, answer all questions truthfully, honestly, and to the best of your knowledge - but more importantly, answer them as specifically as possible. For instance, I remember a question on the flight physical form that asks about surgeries, major illnesses, or broken bones that you have had in the last 2 or 4 years (I can't remember which time frame) - If you broke your arm five years ago, don't volunteer that information unless they specifically ask for it..
I don't know what your surgery was or what bones you broke - as long as you demonstrate to them that it does not hinder you - that you have full range of motion, etc, you should not have a problem. I had broken my arm six times when I was a kid and broke my left clavicle my third year in college (three years ago) - I also had surgery at 9 mos. and 11 years of age - The flight surgeon passed me.
Something to think about - when you contract with the Marines, you sign a waiver giving them permission to review your medical record - I don't know how that works, but I assume they can find out about your broken bones and surgery. Take my advice with a grain of salt, but being truthful up front seems a lot less painful