Children in forceful impacts suffer twice as many pulmonary contusions as adults with similar injury mechanisms, yet have proportionately fewer rib fractures. The rates of certain types of injury mechanisms differ between children and adults; for example, children are more often hit by cars as pedestrians. Some differences in childrens physiology might be advantageous (for example they are less likely to have other medical conditions), and thus they have been predicted to have a better outcome. However, despite these differences, children with pulmonary contusion have similar mortality rates to adults. History
In 1761, the Italian anatomist Giovanni Battista Morgagni was first to describe a lung injury that was not accompanied by injury to the chest wall overlying it. Nonetheless, it was the French military surgeon Guillaume Dupuytren who is thought to have coined the term pulmonary contusion in the 19th century. It still was not until the early 20th century that pulmonary contusion and its clinical significance began to receive wide recognition. With the use of explosives during World War I came many casualties with no external signs of chest injury but with significant bleeding in the lungs. Studies of World War I injuries by D.R. Hooker showed that pulmonary contusion was an important part of the concussive injury that results from explosions.Pulmonary contusion received further attention during World War II, when the bombings of Britain caused blast injuries and associated respiratory problems in both soldiers and civilians.
It was first proposed in 1965 that this respiratory insufficiency is most often due to injury of the lung rather than to the chest wall,  and a group led by J.K. Trinkle confirmed this hypothesis in 1975. Hence the modern treatment prioritizes the management of pulmonary contusion. Animal studies performed in the late 1960s and 1970s shed light on the pathophysiological processes involved in pulmonary contusion. Studies in the 1990s revealed a link between pulmonary contusion and persistent respiratory difficulty for years after the injury in people in whom the injury coexisted with flail chest. In the next decade studies demonstrated that function in contused lungs improves for years after the injury. References
External links

Chest Trauma - pulmonary contusion, trauma.org