The calvaria is the top part of the

skull The skull, or cranium, is typically a bony enclosure around the brain of a vertebrate. In some fish, and amphibians, the skull is of cartilage. The skull is at the head end of the vertebrate. In the human, the skull comprises two prominent ...

. It is the superior part of the

neurocranium In human anatomy, the neurocranium, also known as the braincase, brainpan, brain-pan, or brainbox, is the upper and back part of the skull, which forms a protective case around the brain. In the human skull, the neurocranium includes the cal ...

and covers the

cranial cavity The cranial cavity, also known as intracranial space, is the space within the skull that accommodates the brain. The skull is also known as the cranium. The cranial cavity is formed by eight cranial bones known as the neurocranium that in human ...

containing the brain. It forms the main component of the

skull roof The skull roof or the roofing bones of the skull are a set of bones covering the brain, eyes and nostrils in bony fishes, including land-living vertebrates. The bones are derived from dermal bone and are part of the dermatocranium. In com ...

. The calvaria is made up of the superior portions of the

frontal bone In the human skull, the frontal bone or sincipital bone is an unpaired bone which consists of two portions.'' Gray's Anatomy'' (1918) These are the vertically oriented squamous part, and the horizontally oriented orbital part, making up the bo ...

occipital bone The occipital bone () is a neurocranium, cranial dermal bone and the main bone of the occiput (back and lower part of the skull). It is trapezoidal in shape and curved on itself like a shallow dish. The occipital bone lies over the occipital lob ...

, and

parietal bone The parietal bones ( ) are two bones in the skull which, when joined at a fibrous joint known as a cranial suture, form the sides and roof of the neurocranium. In humans, each bone is roughly quadrilateral in form, and has two surfaces, four bord ...

s. In the

human skull The skull, or cranium, is typically a bony enclosure around the brain of a vertebrate. In some fish, and amphibians, the skull is of cartilage. The skull is at the head end of the vertebrate. In the human, the skull comprises two prominen ...

, the sutures between the bones normally remain flexible during the first few years of postnatal development, and

fontanelle A fontanelle (or fontanel) (colloquially, soft spot) is an anatomical feature of the infant human skull comprising soft membranous gaps ( sutures) between the cranial bones that make up the calvaria of a fetus or an infant. Fontanelles allow ...

s are palpable. Premature complete ossification of these sutures is called

craniosynostosis Craniosynostosis is a condition in which one or more of the fibrous sutures in a young infant's skull prematurely fuses by turning into bone (ossification), thereby changing the growth pattern of the skull. Because the skull cannot expand perpe ...

. In Latin, the word ''calvaria'' is used as a feminine noun with plural ''calvariae''; however, many medical texts incorrectly list the word as ''calvarium'', a neuter Latin noun with plural ''calvaria''.

Structure

The outer surface of the skull possesses a number of landmarks. The point at which the frontal bone and the two parietal bones meet is known as the bregma. The point at which the two parietal bones and the occipital bone meet is known as the lambda. Not only do these landmarks indicate the

in newborns, they also act as reference points in medicine and surgery. The inner surface of the skull-cap is concave and presents depressions for the convolutions of the

cerebrum The cerebrum (: cerebra), telencephalon or endbrain is the largest part of the brain, containing the cerebral cortex (of the two cerebral hemispheres) as well as several subcortical structures, including the hippocampus, basal ganglia, and olfac ...

, together with numerous furrows for the lodgement of branches of the meningeal vessels. Along the middle line is a longitudinal groove, narrow in front, where it commences at the frontal crest, but broader behind; it lodges the superior sagittal sinus, and its margins afford attachment to the falx cerebri. On either side of it are several depressions for the

arachnoid granulations Arachnoid granulations (also arachnoid villi, and Pacchionian granulations or bodies) are small outpouchings of the arachnoid mater and subarachnoid space into the dural venous sinuses of the brain. The granulations are thought to mediate the d ...

, and at its back part, the openings of the parietal foramina when these are present. It is crossed in front by the

coronal suture The coronal suture is a dense, fibrous connective tissue joint that separates the two parietal bones from the frontal bone of the skull. Structure The coronal suture lies between the paired parietal bones and the frontal bone of the skull ...

and behind by the

lambdoid suture The lambdoid suture, or lambdoidal suture, is a dense, fibrous connective tissue joint on the posterior aspect of the skull that connects the parietal bones with the occipital bone. It is continuous with the occipitomastoid suture. Structure T ...

, while the

sagittal suture The sagittal suture, also known as the interparietal suture and the ''sutura interparietalis'', is a dense, fibrous connective tissue joint between the two parietal bones of the skull. The term is derived from the Latin word ''sagitta'', meaning ...

lies in the medial plane between the parietal bones.

Layers

Most bones of the calvaria consist of internal and external tables or layers of compact bone, separated by

diploë Diploë ( or ) is the spongy cancellous bone separating the inner and outer layers of the cortical bone of the skull. It is a subclass of trabecular bone. In the cranial bones, the layers of compact cortical tissue are familiarly known as the ...

. The diploë is cancellous bone containing red

bone marrow Bone marrow is a semi-solid biological tissue, tissue found within the Spongy bone, spongy (also known as cancellous) portions of bones. In birds and mammals, bone marrow is the primary site of new blood cell production (or haematopoiesis). It i ...

during life, through which run canals formed by

diploic vein The diploic veins are large, thin-walled valveless veins that channel in the diploë between the inner and outer layers of the cortical bone in the skull, first identified in dogs by the anatomist Guillaume Dupuytren. A single layer of endothel ...

s. The diploë in a dried calvaria is not red because the protein was removed during preparation of the cranium. The internal table of bone is thinner than the external table, and in some areas there is only a thin plate of compact bone with no diploë. Calvarial bones are supplied by endosteal and periosteal sheaths which are innervated by the nociceptors, sensory, sympathetic, and parasympathetic nerves. Horizontal section of the mouse pups showed that the density of nerve fibers was highest in the region of forehead, temples, and the back of head which crossing the frontal, parietal, and interparietal bones. In the calvarial innervation in the adult mouse, CGRP-labeled fibers and peripherin were seen in the sutures, emissary canals, and bone marrow but not in diploe. Nerve fibers passing through the emissary canals and cavity of bone marrow provided the branches of periosteal and dural nerves whereas fibers from the sutures gave out to the dural nerves. File:Gray769.png File:Gray1196.png

Development

In the fetus, the formation of the calvaria involves a process known as

intramembranous ossification Intramembranous ossification is one of the two essential processes during fetal development of the gnathostome (excluding chondrichthyans such as sharks) skeletal system by which rudimentary bone tissue is created. Intramembranous ossification i ...

In popular culture

In many translations of the

Gospels Gospel originally meant the Christian message (" the gospel"), but in the second century AD the term (, from which the English word originated as a calque) came to be used also for the books in which the message was reported. In this sen ...

Jesus Jesus (AD 30 or 33), also referred to as Jesus Christ, Jesus of Nazareth, and many Names and titles of Jesus in the New Testament, other names and titles, was a 1st-century Jewish preacher and religious leader. He is the Jesus in Chris ...

is killed in a place named "

Calvary Calvary ( or ) or Golgotha () was a site immediately outside Jerusalem's walls where, according to Christianity's four canonical gospels, Jesus was crucified. Since at least the early medieval period, it has been a destination for pilgrimage. ...

", a reference to this body part.

References

External links