Delayed massive hemothorax due to a diaphragmatic laceration caused by lower rib fractures.

A delayed hemothorax requiring surgical treatment is considered a rare minor thoracic injury. We experienced four cases of delayed massive hemothorax due to a diaphragmatic laceration caused by lower rib fractures. A computed tomography scan on admission revealed multiple rib fractures in all patients, and at least one fractured lower rib was severely displaced, which injured the diaphragm. The duration between the injury and the diagnosis were 14 h-30 days. Emergency surgical treatment was performed, and intraoperative findings revealed a diaphragmatic laceration with oozing due to injury caused by the edge of a fractured rib. After the operation, all patients were successfully discharged.