post-thoracotomy pain syndrome (PTPS) and its social consequences have been inconsistently investigated as most studies were either small sized, focused on a limited number of risk factors or included heterogeneous surgical procedures. The current objectives were to obtain detailed information on the consequences of PTPS after thoracotomy and video-assisted thoracic surgery (VATS) from homogenous unselected nationwide data, and to suggest mechanisms for the development of PTPS.