Incidental haemothorax after sublobar resection: did staple line scratch chest wall?

We herein report a case of life-threatening haemothorax that occurred 40 days after pulmonary segmentectomy in a 60-year-old man. The patient uneventfully underwent resection of the apical and posterior segments of the right upper lobe by video-assisted thoracic surgery for early-stage lung cancer. An emergency operation of haemostat for active bleeding from the intercostal artery was successful via a right thoracotomy. The bleeding point was in the vicinity of the staple line dividing the intersegmental plane. This case reveals that scratch by staples can cause haemothorax through incidental injury of the intercostal artery.