Morphologic, morphometrical and histochemical proprieties of the costal cartilage in children with pectus excavatum.

Pectus excavatum (PE) is the most frequent anterior chest deformity occurring in approximately one of 1000 live births. Despite the excellent achievements in the treatment of the disease, the etiology of PE is yet to be clarified. It is believed that the cause for PE is an intrinsic costal cartilage abnormality leading to an overgrowth of the cartilage, which pushes the sternum backward. Several histological studies revealed contradictory results and failed to identify a clear structural abnormality of the costal cartilage responsible for the apparition of PE. In this article, we focused on identifying the microscopic disturbances of the costal cartilage in patients with PE. We obtained cartilage samples from 29 children with PE and 18 control cartilage samples. The samples were subjected to morphologic, morphometrical and histochemical assess. The results indicate a young, immature pattern of the cartilage matrix with a normal cell/matrix ratio. These results sustain the theory that the cause of PE is to be found inside the costal cartilage and the most plausible cause is a global overgrowth of the costal cartilage.