Cranial synchondroses occur where separate centers of ossification occur within a continuous mass of hyaline cartilage. These neighboring centers enlarge to encroach upon one another. The intervening cartilage functions as a proliferative growth spacer during the bones development. In most instances these cartilage spacers are eventually replaced by the developing bone and the two bones fuse together. In the skull the synchondroses occur with in the developing chondrocranium forming the early support for the rapidly developing brain. They occur within and between the occipital, temporal, sphenoid, and ethmoid bones.

Synchondroses cranii

Synchondroses crâniennes