Traumatic ruptures of the diaphragm occur most frequently at blunt injuries of the abdomen or thorax as a component of polytraumatism. At the acute stage they present a serious diagnostic problem since signs of polytrauma are predominant. The authors report 3 cases of traumatic rupture of the diaphragm with thoracotomy as the therapeutic approach. The first patient presented with severe polytraumatism and shock, rupture of the diaphragm, pericardium and lungs, along with serial fracture of the left ribs. The second patient was not in shock, he had suffered serial fracture of the left ribs and fracture of the pelvis. In both these cases of blunt injury to the thorax, careful examination of the patients resulted in early diagnosis and surgery. The third patient presented with open injury of the right side of the thorax, injured diaphragm and liver, serial fracture of the ribs, fractured sternum, and was in a state of deep shock. There was no mortality, all three patients recovered.