I wanted oncology too, fresh out of school. I drove up to Nashville to interview on winter break my senior year, hoping that's where they'd place me.
"We'd like to hire you for 11 South, the neurology and neurosurgery floor", said the nice recruiter.
I don't remember what I said, but I wasn't doing cartwheels at the prospect. He then pointed out that it was medical AND surgical - a selling point, I guess. To which I, naive 21 year old that I was, said, "OK".
Fast forward 6 months, and I am off orientation, in charge, and hating the stupid floor, because I don't have a clue about how to determine a neuro change from say, a stubborn old man who is feigning sleep. The residents are already tired of me, and it's only July. As time went on, though, it got better, I got better, and you know what? Neuro is everywhere in nursing. That first assignment has stood me in good stead over the years.
I finally did oncology, about 5 years later. Really liked it, but no full time positions available and left after 3 months for telemetry, and eventually SICU, where I think I'll stay.
I imagine that ortho will be the same for you. There's a lot of basic med surg there, and frankly, most of those folks are going to get better and leave the hospital fairly soon. In the meantime, you're learning all about mobilizing patients, how NOT to screw up a hip or knee replacement, and oh boy, will you know a thing or two about pain control. Probably never going to be your dream job, but hey! Fake it till you make it. At least for the interview.
Good luck! I hope you get where you want to be. Keep us posted.