It is also called floating chest wall, which is one of the clinically serious closed chest trauma, and the mortality rate can be as high as 16%~42%, due to multiple rib fractures, or multiple rib fractures combined with rib and rib cartilage junction separation or combined with sternal fractures, the injured part of the chest wall loses rib support and softens, forming a floating chest wall, which is depressed inward during inspiration and protrudes outward during inspiration, forming a “paradoxical respiratory movement” opposite to the healthy chest wall. Chest wall direction opposite to the “anomalous respiratory movement”, so that both sides of the chest pressure imbalance, mediastinum swing back and forth with breathing, affecting blood return, causing circulatory disorders, leading to and aggravating shock caused by death, so when the patient suffers from the symptoms of shackle chest need to go to the hospital as soon as possible for diagnosis and treatment, so that it can be cured as soon as possible. Diagnostic criteria: 1, after severe chest trauma, extensive damage to the chest and back, deformity with severe respiratory distress, even if there is not yet obvious paradoxical breathing (especially in obese patients), the possibility of the formation of conjoined thorax should be considered. 2, the scope and degree of chest wall softening, reflecting the severity of shackle chest; the wider the scope of chest wall softening, the more serious the paradoxical breathing and respiratory distress, rescue measures should be taken immediately. 3, the broader the range of chest wall softening, the more serious the paradoxical breathing and respiratory distress patients, more combined with intra-thoracic organ damage. At this time, while dealing with the shackled chest, we must closely observe the changes in the condition (respiration, blood pressure, blood gas analysis, etc.), and conduct corresponding examinations and take timely rescue measures. 4, for patients with combined multiple injuries outside the chest, often ignore the presence of inconspicuous shackle chest. Information can be obtained from the patient’s dyspnea, degree of cyanosis, thoracic deformity and atypical paradoxical breathing. 5, under the examination of chest X-ray can not only understand the severity of shackled chest, but also can find out the type and specific situation of injury of intra-thoracic organs, such as pericardial effusion, mediastinal pneumothorax, etc. 6.The severity of hypoxemia and the abnormalities of other blood gas items in the blood gas analysis examination are important for the diagnosis and treatment of shackled chest and improvement of respiratory disorders.