The parietal bone, like all other structures of the human body, has its own anatomical features. They are caused by those tasks, the implementation of which is entrusted to this region of the skull.
Anatomical structure of the parietal bone
Currently, this aspect is known very, very well. The parietal bone is a kind of quadrangle. This structure has a flattened shape.
The parietal bone is paired. Both of them have absolutely no differences. The parietal bone left and right are connected to each other by their upper edges. They are called sagittal. These edges are fastened with the same seam. The frontal and parietal bones are connected in front. In this case, the first of them wedges into the second a little. This is due to the fact that the frontal edge of the parietal bone has a slightly concave shape.
The lower edge of this anatomical structure is called scaly. It is so named because of the surface changing somewhat at this place. This edge connects the parietal bone with the temporal bone.
There is also an occipital margin. It borders on the bone of the same name. This edge has a slightly convex shape.
In addition, the parietal bone also has 4 edges. The one that is located between the occipital and temporal bone is called mastoid. Above it is the occipital angle. A wedge-shaped angle is located between the frontal and temporal bones. A little higher from it is the frontal angle.
"Surface" anatomy
The parietal bone does not have a flat structure. The fact is that its outer surface is convex, and the inner, on the contrary, is concave. A similar anatomical structure of the parietal bone is due to the need for a relatively tight fit to the brain.
The outer surface is relatively smooth. As for the internal, it is quite heterogeneous. The fact is that on this surface there is a large number of arterial furrows. They are necessary for additional protection of blood vessels supplying such an important organ as the brain.
On the inner surface of the parietal bone in the area of the mastoid angle is a sigmoid sinus groove.
The functions of the parietal bone
First of all, it is part of the skull. The main task of this bone is to protect the skull from any damaging effects of the external environment. First of all, we are talking about the patronage of the central organ of the entire nervous system from various kinds of strokes and other traumatic effects.
Another important function of the parietal bone is to protect the brain from low temperatures. Also, to a certain extent, the hairline also performs this role.
About pathology in the structure of the parietal bone
This area often becomes the place of formation of one or another pathological process. Currently, the most common of these are the following:
- osteoma;
- cephalohematoma;
- hyperostosis
- all kinds of injuries.
Osteoma
It is a benign tumor. Its feature is the so-called exophytic growth (i.e. outward). It is because of this that it does not pose a serious danger to human health. The main nuisance here can only be a cosmetic defect. Such a benign tumor grows extremely slowly.
Diagnosis of the disease is carried out using x-ray studies, as well as computed tomography.
As for the treatment, it is carried out according to the treatment of the patient by removing part of the parietal bone. In the event that this section exceeds 2 cm 2 in area , the resulting hole is closed with a special material.
Kefalogematoma
This pathology in the vast majority of cases develops during childbirth. This occurs during the interaction of the skull of the baby being born and the birth canal of his mother. As a result of the constant mechanical effect that occurs on the parietal bone during childbirth, hemorrhage occurs under the periosteum. In children, the coagulation abilities are much less than in adults, so the cephalohematoma can grow over several days. At the same time, due to the anatomical features of this region, such a pathological process never goes beyond the borders of the parietal bone.
Diagnosis of cephalohematomas is based on a routine examination, as well as an ultrasound scan.
In the case of minor hemorrhages, treatment may not be required. Over time, the resulting cephalohematoma resolves independently. If the amount of blood is large enough, then it is necessary to remove it with a puncture. In cases where, in addition to cephalohematoma, damage to the skin also occurs, it is necessary to conduct a course of treatment with antibacterial drugs, otherwise significant complications may occur.
Hyperostosis
This deviation from the norm is the formation of excessive layers on the surface of the parietal bone. As a result, it turns out to be somewhat thicker than usual. Such a pathology does not have any clinical manifestations. This is due to the fact that most often this deviation from the norm becomes an accidental finding in the process of radiography or computed tomography of the skull, appointed for completely different reasons.
Hyperostosis treatment is not required. It not only does not harm health, but does not even manifest itself as a cosmetic defect.
Injuries
Most often, the pathology of the structure of the parietal bone is traumatic. In the vast majority of cases, a defect occurs precisely at the place of application of force. In this case, fractures of the parietal bone have several varieties at once:
- linear
- depressed;
- comminuted.
Linear fractures suggest the formation of a crack. Usually this is preceded by a serious compression of the skull from the outside. Depressed fractures are characterized by the presence of a part of the bone deflected into the cranial cavity. As for comminuted fractures, they suggest the division of the parietal bone into several separate parts. In this case, usually only some specific part of it suffers.