[A sharp edge of the fractured ribs caused the aortic injury at body-position change: a case report].

The reported patient was a 37-year-old male, who got a blunt chest trauma by a motor vehicle accident. Chest X-ray and computed tomography of the chest revealed bilateral multiple rib-fractures, pneumo-hemothorax, lung contusions, but no evidence of mediastinal hematoma. Since respiratory distress with a flail chest was observed, the patient was placed on an artificial ventilation, and thoracocentesis were also done on both sides, while the hemodynamics was fairly maintained with blood transfusion. On the 10th hospital day, however, he suddenly fell into a deep shock with the left hemothorax by changing the body position. Emergency thoracotomy demonstrated the laceration of the descending aorta, that was considered to be made by the sharp edge of the fractured left 8th rib, which correspondingly protruded into the thoracic cavity toward the aorta. The repair of the aortic injury and the resection of the rib edges were performed. He was discharged on the 45th hospital day. In cases with a blunt chest trauma, the majority of the causes of the traumatic aortic injury are reported to be "deceleration injury". Although the considered mechanism of the traumatic rupture of the thoracic aorta in this case is extremely rare, it should be taken into a consideration for treatment of the cases with a blunt chest trauma and multiple rib-fractures.