The thorax has protective (mobile) walls around the vital cardiorespiratory viscera.
This protection prevents palpation except for transmitted input and (implied) movement.
The regions that make up the module are walls and contents. Impalpable contents emphasize the importance of surface knowledge.
Where all the major viscera share a sensory supply (T4/5), knowledge of neurosomes is the only way to truly make sense of referred pain.
The concealed nature of thoracic viscera makes investigation more likely.
Pneumothorax may be spontaneous or traumatic.
Spontaneous pneumothorax is common in young males. It is probably related to a congenital or acquired defect. Both lungs are affected with equal frequency. In patients over 40, it is usually caused by chronic airways disease.
The leak may be localized if adhesions are present - more likely, it is generalized. The negative intrapleural pressure becomes positive and the elastic recoil of the lung causes it to collapse towards the hilum. An open passage between lung and pleural cavity creates a bronchopulmonary fistula. If the passage closes off, air will be reabsorbed.
If the soft tissue around the passage acts like a valve (air sucked into the space but not expelled), a tension pneumothorax is present.
Presenting symptoms are dyspnea and pain.
Physical signs vary with the severity, as does the treatment.
Complications include hemothorax and those of the actual traumatic cause.
Foreign bodies within the thorax may be bronchial or esophageal. They come to rest in these structures if they pass through the more proximal narrowings.
Intrabronchial foreign bodies are relatively common in children (though the anatomy is different). Objects include bones, teeth, nuts and small toys.