Funnel chest is a congenital and often familial condition commonly known as collapsed chest, more common in males than females (4:1). The cause of funnel chest is unknown and is thought to be genetically related, being a companion dominant inheritance; in addition, rickets, which is caused by vitamin D deficiency causing calcium, phosphorus, and other minerals to not be deposited on the bones, in some cases causing deformities of the legs and in others causing deformities of the pediatric thorax. Funnel chest is a progressive lesion that may be present at birth, but often becomes more pronounced and detected by parents only after a few months or even years. The external appearance is characterized by a sunken anterior chest, anterior extension of the shoulders, a slight hunchback and a prominent epigastrium. I. What are the symptoms of funnel chest? 1) Funnel chest is very easy to find clinically, the deformity is obvious at a glance, i.e. the sternum, rib cartilage and part of the rib cage are depressed towards the spine to form a “funnel shape”. Children often present with a distinctive weak posture: forward neck, rounded cut shoulders, and a potted abdomen. 2) A mild funnel chest can be asymptomatic, while a more severe deformity compresses the heart and lungs, affecting respiratory and circulatory functions. Children with reduced lung capacity are prone to recurrent respiratory infections, which affects their physical development; older ones can have dyspnea, rapid pulse, palpitations, and even pain in the precordial region after activity, and some patients can also have arrhythmias, as well as systolic murmurs. 3) Funnel chest is sometimes combined with pulmonary dysplasia, Marfan syndrome, asthma and other diseases, which often become intolerable deformities when combined. Diagnostic tests of funnel chest: 1) X-ray chest examination: the lower sternum is depressed backward, and the distance between it and the spine is shortened; the heart shadow is mostly displaced to the left side of the chest, and there is an obvious radiographic translucent area in the middle of the heart shadow, and the right heart margin often overlaps with the spine; lateral chest film can see the sternal body is obviously bent backward, and the lower end of the sternum can reach the anterior edge of the spine in some cases. 2) Chest CT film: it can clearly show the severity of thoracic deformity and the degree of heart compression and displacement. 3)Electrocardiogram (ECG): it shows inverted or bidirectional P waves of V1, and there can also be right bundle branch conduction block. 4)Cardiac catheterization: can be traced to diastolic slopes and plateaus, the same as seen in constrictive pericarditis. 5) Cardiovascular angiography: shows right heart compression malformation and right ventricular outflow tract obstruction. C. Why does funnel chest need treatment? 1) It seriously affects the physical beauty and can cause inferiority complex and self-containment in young children. 2) It affects the function of the body such as heart and lungs. Fourth, funnel chest treatment: mild funnel chest can be improved by strengthening nutrition and exercise; if it is caused by vitamin D deficiency, calcium and vitamin D can be supplemented, and more sunshine; if it is a serious funnel chest and affects the physical and mental development of children, it is necessary to go to the hospital for examination, and for children with moderate and severe funnel chest, surgery is appropriate to correct the deformity. (I) Traditional surgery: 1) Riboplasty: applicable to unilateral deeper funnel chest that does not involve the sternum. 2)Sternal elevation: this method may be less popular because of the possibility of paradoxical breathing after surgery. 3)Sternal rib elevation: particularly suitable for younger patients whose rib cartilage rib bones are all relatively tender. 4)Sternal reversal with inferior vascularization and tipped sternum: this method does not cut off the arteries and veins in the thorax and the blood circulation of the rectus abdominis sternum can be kept normal, which ensures the normal growth and development of the sternum after surgery, the chest wall is stable after surgery, and patients without paradoxical breathing can go down to the floor as soon as possible, with satisfactory results of deformity correction. 5) Sternal reversal with rectus abdominis: This method cuts off the arteries and veins in the thorax and retains only the rectus abdominis as the source of blood supply. 6) In addition, there are also sternotomy without a tip, sternotomy with overlap, etc. (B) Minimally invasive surgery Minimally invasive Nuss surgery for funnel chest is to implant a tailor-made metal plate (Pectus Bar) under thoracoscopic guidance to push outward the sternal depression to do corrective surgery all the inwardly concave deformed rib cartilage is also pushed outward with the metal plate, neither cutting the ribs nor cutting the pectoralis major muscle. The metal plate is left in the body for about 2 to 5 years and then removed. The minimally invasive Nuss procedure has been called a revolution in chest wall orthopedic surgery because of its small and concealed incision, short operative time, minimal bleeding, early activity, no free chest wall muscle flap, no removal of rib cartilage or sternum, and long-term maintenance of chest extension, expansion, flexibility and elasticity. Since Nuss surgery is a minimally invasive and easy-to-grasp surgical technique, it is rapidly accepted by pediatric surgeons and thoracic surgeons around the world because it minimizes surgical trauma, reduces postoperative pain, shortens postoperative recovery time, lowers surgical costs, bleeds less, and does not require blood transfusion compared to traditional surgical treatments for funnel chest (such as sternal reversal) with open chest, while ensuring surgical results. The procedure is indicated for patients with funnel chests in the age range of 3 to 50 years, as well as for patients who have failed to be treated with conventional surgery.