Thoracoscopic findings of an asymptomatic solitary costal exostosis: is surgical intervention required?

We report a case of a 21-year old male with an asymptomatic solitary costal exostosis incidentally detected on a chest X-ray. The exostosis originated from the costochondral junction of the left fourth rib and protruded into the thoracic cavity. Exploratory thoracoscopy showed that the exostosis had scratched the adjacent pericardium and visceral pleura. A 5.5-cm long rib segment including the exostosis was excised. This report describes that the thoracoscopic findings of an asymptomatic costal exostosis originate from the costochondral junction, demonstrating that this condition may cause more extensive thoracic organ injury than expected.