No that's not true in my experience. I've done research and publications in general surgery, radiology, and ortho. Ortho was the only one in my experience that I had rejected (multiple times, at that). My PI in ortho had a similar history of rejections and settling to publish in lesser journals.
My rejected project was a clinical project - I imagine basic science/transitional ortho projects may be easier to get published than clinical research.
This is just my experience and may not be representative of the field versus others as a whole. If ortho is what you want to do, then do research in it. However, if you want a field that's "easy to publish in", all fields have shoddy journals that take the rejections of the bigger journals. Find a PI at your institution that has a good publishing history.