How can you tell if elbow is broken?

An x-ray: The best way to diagnose a fracture a bone or joint is my getting an x-ray. This coupled with an evaluation by an orthopedic surgeon will establish the diagnosis and determine the treatment plan.

X-ray: An x-ray would be the best thing.

Exam and xray: If you have persistent, severe pain and a sufficient mechnism in which you could have fractured your elbow (such as a fall), then an exam and xray to see if you have fractured your elbow would be strongly encouraged.

With X-ray, : History and physical exam - yes.