The parietal bone, like all other structures of the human body, has its own anatomical features. They are due to the tasks, the implementation of which is entrusted to this area of the skull.
Anatomical structure of the parietal bone
Currently, this aspect is known very, very well. The parietal bone is a kind of quadrilateral. This structure has a flattened shape.
The parietal bone is paired. Both of them have absolutely no difference. The parietal bone left and right are connected to each other by their upper edges. They are called sagittal. These edges are fastened with a seam of the same name. The frontal and parietal bones are connected in front. In this case, the first of them is slightly wedged into the second. This is due to the fact that the frontal edge of the parietal bone has a somewhat concave shape.
The lower edge of this anatomical structure is called squamous. It is so called because of the slightly changing surface in this place. This edge connects the parietal bone with the temporal.
There is also an occipital margin. It borders on the bone of the same name. This edge has a slightly convex shape.
Besides this, the parietal bone also has 4 edges. The one that is located between the occipital and temporal bones is called the mastoid. Above it is the occipital angle. Between the frontal and temporal bones is a wedge-shaped angle. 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. Such 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 are a large number of arterial furrows. They are necessary for additional protection of the vessels that supply blood to such an important organ as the brain.
On the inner surface of the parietal bone in the region of the mastoid angle is the groove of the sigmoid sinus.
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 protection of the central organ of the entire nervous system from various kinds of blows and other traumatic influences.
Another important function of the parietal bone is to protect the brain from low temperatures. Also this role inthe hairline also performs to a certain extent.
About the 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;
- different kinds of injuries.
Osteoma
She is a benign tumor. Its feature is the so-called exophytic growth (that is, outward). Because of this, it does not pose a serious danger to human he alth. Only a cosmetic defect can become the main trouble here. Such a benign tumor grows extremely slowly.
Diagnosis of the disease is carried out using X-ray examination, as well as computed tomography.
As for the treatment, it is carried out at the request of the patient by removing part of the parietal bone. In the event that this area exceeds 2 cm in area 2, then the resulting hole is closed with a special material.
Cephalhematoma
This pathology in the vast majority of cases develops during childbirth. This happens when the skull of the baby born and the birth canal of his mother interact. As a result of the constant mechanical impact that is exerted on the parietal bone during childbirth, hemorrhage occurs under the periosteum. In children, coagulation abilities are much less than inadults, so cephalohematoma can grow over several days. At the same time, due to the anatomical features of this area, such a pathological process never goes beyond the parietal bone.
Diagnosis of cephalohematoma is based on a routine examination, as well as an ultrasound examination.
In the case of minor hemorrhages, treatment may not be required. Over time, the resulting cephalohematoma will resolve on its own. 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, there is also damage to the skin, 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. There are no clinical manifestations of this pathology. This is the reason for the fact that most often this deviation from the norm becomes an accidental finding in the process of X-ray or computed tomography of the skull, appointed for completely different reasons.
Treatment of hyperostosis is not required. It not only does not harm he alth, but does not even appear as a cosmetic defect.
Injuries
Most often, the pathology of the structure of the parietal bone is traumatic. In the vast majority of cases, the defect occurs precisely in the place where the force is applied. In this case, fractures of the parietal bone haveseveral 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 involve the division of the parietal bone into several separate parts. In this case, only a certain part of it usually suffers.
