This air usually enters the pleural space through a hole in the lung or through an injury in the chest wall. In these young men, the increased length of the chest may somehow contribute to bleb formation in the lungs.
Cigarette smoking is also a factor in most patients.
About 20,000 new cases of spontaneous pneumothorax are diagnosed each year in the United States. For example, trauma from a car accident or a stab wound can allow air into the pleural space, causing the lung to collapse. Pneumothorax also can occur when the lung or chest wall is damaged during a medical procedure. In tension pneumothorax, air accumulates under pressure inside the pleural space. Pneumothorax related to menses - This rare form of pneumothorax occurs in otherwise healthy women during menstruation.