How do you tell if a finger is broken?

X-rays. Sometimes, it is grossly evident that a finger is broken because it is deformed, but this is certainly not always the case. If you are concerned that your finger may be broken, i would suggest seeing an orthopaedic surgeon for an exam and x-rays.
Pain, swelling. Decreased motion, ecchymoses ( black and blue) deformity, crepitance ( crunchy bone sounds) and finally an x-ray.

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How do you tell if your finger is broken or jammed?

See your doctor. Your doctor will perform a physical exam and consider ordering an x-ray if he/she feels that the finger may be broken. Read more...