General information
Ossification is the formation of boils. A distinction is made between the formation of bone from connective tissue, which is called desmal ossification, and chondral ossification, in which bone is formed from existing cartilage. Usually, ossification is a natural process that builds up the incomplete skeleton, especially in childhood.
However, increased ossification can also occur in the context of diseases, which can cause problems if the bone grows where it is not intended. In order to understand ossification, it is very helpful to know the structure of a bone, so here are some basics about bone. Basically there are different forms of bone, on the one hand the typical tubular bones, which are, as the name suggests, elongated.
Typical representatives are the humerus, which the medical profession calls humerus, or the femur, which is called femur. These bones are filled inside with bone marrow that is very well supplied with blood. In addition, there are also so-called flat bones, which are rather two-dimensional, such as most skull bones.
Then there are so-called “sesamoid bones”, which look rather roundish and untypical, for example the kneecap or some hand bones. In addition, there are exotic bones like the air-filled bones, which are hollow inside, these are the bones of the facial skull, which contain the paranasal sinuses. The head of tubular bones is called “epiphysis”, the transition to the actual “tube” is called metaphysis and the tube itself is called diaphysis.
The individual bone consists of a fine periosteum that completely surrounds it. This contains the “Compacta” or “Corticalis”, a particularly dense bone structure that gives the bone its strength. The fibers of the tissue are uniformly aligned, which further strengthens them.
Inside there is a looser structure called “cancellous bone”, which means spongy. On the very inside is the bone marrow cavity. In it there is either fat marrow or blood-forming red bone marrow, which is very well supplied with blood.
The bone tissue itself is a mixture of inorganic and organic substances and a quarter of water. The inorganic parts consist mainly of hydroxyapatite, which is composed of calcium and phosphate. In addition, the organic collagen is also present in the bone.
This is a protein that also occurs in the skin. Between the bone tissue there are individual cells, the so-called “osteoblasts” and “osteoclasts”. The osteoblasts produce the bone substance and are connected to each other by fine tubules.
The osteoclasts in turn are the antagonists and break down the bone. As mentioned above, the bones are uniformly arranged in the compacta. This is why they are also called lamellar bones.
They are the typical bone structure. In a fracture, on the other hand, a meshwork bone is formed first, in which the fibers of the tissue grow crosswise. Only gradually does the bone gradually become lamellar bone again, which can then regain its full stability.
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