Watch patients interact with healthcare providers, even on television or in the movies. When a tiny little break is barely discernible on an X-ray, the healthcare provider will point it out—usually with a ball-point pen—and say, “here’s the fracture.”
Why not say “Here’s the break?” Probably because it doesn’t sound doctorly. The same healthcare provider is going to walk out of the room and tell their colleague that the patient broke their whatever. Healthcare providers like to sound educated, but they let their guard down with peers.
To be fair, while you can use both break and fracture as either nouns or verbs, break sounds more like an action and fracture sounds more like a thing.