[Cloverleaf skull and other malformations of the skull. Pathology and clinical aspect].

Malformations of different parts of the cartilage results in achondrogenesis II, thanatophoric dwarfism and in metatropic dwarfism. Whether the base of the skull or the cranial-distal skeleton are affected, both together or separately, depends upon the localization of the defect within the cartilage. The different types of the cloverleaf syndrome are characterised by a defect of vessels and cartilage that affect the chondrocranium and the cranial-distal skeleton in different grades. The mal-development of the vessel-system is particularly marked in the upper back of the calotte.