Idiopathic spontaneous rupture of an intercostal artery.

Spontaneous rupture of an intercostal artery is exceptionally rare without an inciting event such as trauma or nontraumatic arterial wall weakening. This report details the diagnosis and treatment of a 47-year-old man who presented with a spontaneous hemothorax from an intercostal artery. There are very few reports in the literature documenting spontaneous intercostal artery rupture without associated illness or injury.