"Closed” means that the fractured ends of bone did not penetrate the skin. Even a well-healed sternum can hurt for a very long time, even indefinitely. The occasional pain is a nuisance but is not necessarily a sign of less than optimum healing. Another chest x-ray, specifically of the sternum would answer that question. If it has not healed properly, surgical intervention with wiring might be indicated. However, such therapy should not be considered, simply on the basis of a chest x-ray. Severity of symptoms must be taken into account and the description provided suggests that the recurrent pain is mild and not at all disabling.