The diaphragm is the major muscle of respiration. Innervated by the phrenic nerve, the diaphragm is the musculotendinous boundary between the negative-pressure thoracic cavity and positive-pressure abdominal cavity. Upon diaphragmatic contraction, the chest wall expands and the increase in the negative intrathoracic pressure required for inhalation is produced. As the diaphragm plays an essential role in respiratory mechanics, any form of diaphragmatic rupture and subsequent herniation of intra-abdominal contents can be associated with significant morbidity and mortality.
Diaphragmatic hernias can be classified as either congenital or acquired. While congenital diaphragmatic hernias occur due to an embryological defect in the diaphragm and…show more content… Penetrating trauma usually leads to smaller tears in the diaphragm approximating the size of the penetrant. Blunt trauma, however, may be viewed as indirect injury and caused by a sudden increase in intra-abdominal pressure. This results in larger radial tears of the diaphragm. Motor vehicle accidents account for greater than 90 percent of the total blunt diaphragmatic ruptures seen, with the remaining 10 percent due to crush injury. The increased intra-abdominal pressure, as a result of these two mechanisms, overcomes the normal tensile strength of the diaphragm causing it to…show more content… This is likely because patients may initially present with vague symptoms related to their recent trauma, but none that directly suggest an injury to the diaphragm. In one series of delayed diagnosis of traumatic diaphragmatic rupture, 19 percent had their injuries missed even after an initial laparotomy. Late presentation of traumatic diaphragmatic injury may occur at any time after the patient's discharge from hospital, but most likely to manifest when herniation occurs . The greater the time delay to presentation, the longer the defect can mature and the more likely herniation becomes. Post-traumatic hernias have been described presenting 40 years or more after the initial