Definition
The skull (Latin: cranium) is the bony part of the head, the skeleton of the head, so to speak.
Bony structure
The human skull consists of many bones, which however are firmly fused together by the bone sutures (sutures). These sutures belong to the false joints. In the course of life, these sutures gradually ossify and are then called synostoses.
Directly after birth, however, the bone sutures are not yet fully formed in some cases. There are gaps in the bones, the so-called fontanelles, which is why the head of newborns still feels soft in certain places, since there is no bone here yet. During the first years of life, the fontanelles normally close up in a certain way. However, if the bones grow together incorrectly in the further course of life, characteristic changes in the shape of the head occur, for example
- Scaphocephalos (“tooth-shaped”) or to
- Trigonocephalos (triangular).
Classification
For anatomical purposes the skull is divided into two parts: The cranial skull consists of 8 bones: In addition, in the Neurocranium, the roof of the skull (skull calvaria) can be distinguished from the base of the skull. There is direct contact between the skull and the spinal column via two head joints. The spinal cord emerges through an opening in the base of the skull and runs in the spinal canal in the spine to the coccyx.
The bones of the cerebral skull house our brain and are an important protection of the brain against external influences. For this purpose, the brain does not lie directly on the bone, but is embedded once again in a liquid (the cerebrospinal fluid or liquor) so that shocks or similar can be absorbed more easily.
- The brain skull (Neurocranium) and
- The facial skull (Viscerocranium).
- The unpaired occipital bone (Os occipitale),
- The paired parietal bone (Os parietale),
- The paired temporal bone (Os temporale),
- The unpaired sphenoid bone (Os sphenoidale),
- A part of the frontal bone (Os frontale) and the
- Unpaired ethmoid bone (Os ethmoidale).
