Will an x-ray show if there was a broken bone that had healed?

A lot of the resulting x-ray views of a healed bone depend on the severity and type of break. If it were a small fracture, there could be little or no evidence of the injury. More serious fractures of breaks will leave a darker line of scar tissue. Unset breaks will may result in an offset healing with bones mending, but not straight or properly. Severe bone scarring may take the form of lumps or tumor looking masses. Of course any break requiring screws or plates will show any remaining hardware and scarring or marking of the holes drilled for placement and securing, as well as the scarring from the healed bone.