Are the Bones of the Cranial Vault in Newborns Connected to Each Other by Sutures?

The skull of a newborn differs from the skull of an adult in many aspects, including the shape of the sutures and the presence of fontanelles. The sutures in an adult's skull that connect adjacent bones are fixed fibrous joints “synarthroses”. The edges of the bones are serrated like sutures. On the other hand, in newborns these joints are flexible and slightly mobile with wide gaps where more than two bones meet. These gaps are called fontanelles, and they close later as the baby grows. Fontanelles are of great clinical importance in monitoring normal growth and checking for diseases that may affect children. Although the joints of the cranial bones are quite different in newborns than in adults, some authors call them sutures in both cases. This may be inaccurate, and a distinction must be made between the terms in both cases, which may express quite different structures. Therefore, we suggest calling them fibrous joints with an interosseous membrane rather than sutures in newborns.