Beijing:
A 26-year-old man in China suffered an unusual injury - he yawned so hard that his lung collapsed. Ou, from Wuhan in China's Hubei Province, likely ripped a hole in his lung when he stretched and yawned in the morning, doctors said.
Ou felt a sudden pain in his chest but ignored it.
However, he had to go to the Central Hospital of Wuhan when the pain intensified and he couldn't breathe, 'Global Times' reported.
Doctors discovered Mr Ou had suffered from spontaneous pneumothorax, or when a small air pocket in the lung breaks and leaks air into the cavity surrounding the lung.
Chen Baojun, director of cardiothoracic surgery at the hospital, said that while there are many causes for pneumothorax, tall and thin men between 18 and 30 years of age are known to be susceptible.
Ou is 1.8 meters tall and weighs 60 kilogrammes, doctors said.