The calvaria is the top part of the
skull
The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, the ...
. It is the upper part of the
neurocranium
In human anatomy, the neurocranium, also known as the braincase, brainpan, or brain-pan 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 calvaria (skull), ...
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 minus the mandible is called the ''cranium''. The cavity is formed by eight cranial bones known as the neurocranium that in ...
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 and all land-living vertebrates. The bones are derived from dermal bone and are part of the dermatocranium.
In comparati ...
.
The calvaria is made up of the superior portions of the
frontal bone
The frontal bone is a bone in the human skull. The bone consists of two portions.''Gray's Anatomy'' (1918) These are the vertically oriented squamous part, and the horizontally oriented orbital part, making up the bony part of the forehead, par ...
,
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 overlies the occipital lobe ...
, and
parietal bone
The parietal bones () are two bones in the Human skull, skull which, when joined at a fibrous joint, form the sides and roof of the Human skull, cranium. In humans, each bone is roughly quadrilateral in form, and has two surfaces, four borders, an ...
s. In the
human skull
The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, the ...
, 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 f ...
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 list the word as ''calvarium'', a neuter Latin noun with plural ''calvaria''.
Structure
![Functional architecture of cranium](https://upload.wikimedia.org/wikipedia/commons/3/38/Functional_architecture_of_cranium.jpg)
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 "Bregma". The point at which the two parietal bones and the occipital bone meet is known as "Lambda".
Not only do these landmarks indicate the
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 f ...
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, 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 olfactory bulb. In ...
, 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
The falx cerebri (also known as the cerebral falx) is a large, crescent-shaped fold of dura mater that descends vertically into the longitudinal fissure between the cerebral hemispheres of the human brain,Saladin K. "Anatomy & Physiology: The Uni ...
.
On either side of it are several depressions for the
arachnoid granulations, and at its back part, the openings of the
parietal foramina
A parietal foramen is an opening in the skull for the parietal emissary vein, which drains into the superior sagittal sinus. Occasionally, a small branch of the occipital artery can also pass through it. It is located at the back part of the pariet ...
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. It r ...
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
Th ...
, 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
![Gray564](https://upload.wikimedia.org/wikipedia/commons/a/a5/Gray564.png)
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.
In the cranial bones, the layers of compact cortical tissue are familiarly known as the tables of the skull; the outer one is ...
. The diploë is cancellous bone containing red
bone marrow
Bone marrow is a semi-solid tissue found within the 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 is composed of hematopoietic ce ...
during life, through which run canals formed by
diploic veins. 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 is a ...
.
In popular culture
In many translations of the
Gospels
Gospel originally meant the Christian message ("the gospel"), but in the 2nd century it came to be used also for the books in which the message was set out. In this sense a gospel can be defined as a loose-knit, episodic narrative of the words an ...
,
Jesus
Jesus, likely from he, יֵשׁוּעַ, translit=Yēšūaʿ, label=Hebrew/Aramaic ( AD 30 or 33), also referred to as Jesus Christ or Jesus of Nazareth (among other names and titles), was a first-century Jewish preacher and religious ...
is killed in a place named "
Calvary
Calvary ( la, Calvariae or ) or Golgotha ( grc-gre, Γολγοθᾶ, ''Golgothâ'') was a site immediately outside Jerusalem's walls where Jesus was said to have been crucified according to the canonical Gospels. Since at least the early mediev ...
", a reference to this body part.
References
Further reading
*
External links
*
*
Calvaria
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Skull
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no:Skalletak