Chest Wall Deformities

Chest wall deformities may be congenital or acquired and may be divided into three categories. The most common category is the group of deformities in which there is rib overgrowth causing either adepression (Pectus Excavatum) (Fig. 25.1) or protrusion (Pectus Carinatum) (Fig. 25.2) of the anterior chest wall. The second category of deformities is due to failure of normal development (aplasia or dysplasia). The aplasia may be midline causing bifi d sternum, in which there is partial or complete failure of midline fusion of the sternum resulting in ectopia cordis (Figs. 25.3 and 25.4). In addition to the sternum, there may be aplasia of the associated structures, such as the heart, pericardium, diaphragm and anterior abdominal wall (Pentalogy of Cantrell). The aplasia may also be unilateral with an absence of ribs, pectoralis muscles and breast tissue as seen in Poland's Syndrome (Fig. 25.5). The third category of deformities is due to trauma or pressure effects. Too early and extensive rib resection for pectus excavatum may destroy growth centers and result in acquired asphyxiating chondrodystrophy (Fig. 25.6). Abnormal pressure effects and spasticity as seen in patients with severe cerebral palsy may result in very abnormal chest confi guration.

Chest wall deformities are frequently familial with several members of one family affected. The incidence of connective tissue disorders such as Marfan's Syndrome and Ehler's-Danlos Syndrome is markedly increased in patients with chest wall deformities. As a result, systemic weakness of the connective tissues and poor muscular development of the thorax, abdomen and spine is common and scoliosis is present in up to 19% of these patients.