General Information About Bones
Apart from very simple animals, it forms the basis of body structure in most living things, determines the general shape and size of the whole body and its individual parts, and also determines the body and various organs. There is a Skeleton that acts as a support.
Human skeleton In very early ages, the skeleton of the human embryo consists of chorda dorsalis and sclerotome extensions made of embryonal connective tissue. After a while, the embryonal connective tissue, which forms the skeleton, takes the form of cartilage tissue. Only some skull bones and the tissue of the clavicle outline develop as connective tissue. 9-10th of intrauterine life. The ossification of the drafts made of cartilage tissue begins in the 2nd week. The ossification of skeletal parts continues after humans are born, takes a very long time, and ends only between the ages of 22 and 25. During this period, various skeletal parts of man consisted of separately ossified parts connected to each other by cartilage tissue. The shape, size and number of the ossified fragments and the cartilage fragments in between vary greatly according to the bone and age.
206 bones of various shapes and sizes form the skeleton that supports the whole body and various organs by being connected to each other in a particular order and system for the human species. The skeleton is also the basis of the body structure and various organs made of soft tissues are based on this principle and all organs are connected to the skeletal parts either directly or through other organs. Bones, which are connected to each other through various movable joints, act as levers while activating our various body parts. Furthermore, by limiting the spaces for the head and thoracic cavities, the bones protect the important organs in these cavities against external influences. Bones must be made of hard, solid and durable tissue in order to support our body, which weighs 60-70 kilograms, to act as leverage during the movements of our rather heavy body parts, and to protect our important organs such as the brain, heart and lungs. If we examine the fine structure of bones, we will see that there are qualities sought in bones in terms of the function of the tissue.
Bone tissue consists of 33% organic and 67% inorganic substances. 86% of inorganic substances are made of calcium phosphate, 10% of calcium carbonate, 1.5% of magnesium phosphate, 0.5% of calcium fluoride and calcium chloride and 2% of alkaline salts. Inorganic substances provide the hardness of the bone, and organic substances provide its elasticity. These two kinds of substances are very tightly connected to each other in the bone tissue, and this close relationship between organic and inorganic substances is seen even in the smallest details of the bone structure.
If we leave any piece of bone in acid for a while, all the inorganic salts in the bone tissue dissolve and disappear from the tissue. A bone treated in this way loses its stiffness, but retains its shape and elasticity. If we destroy the organic matter by burning the bone, the bone still retains its shape, but loses its elasticity and strength, breaks down with a little force and turns into powder. The fact that the bone retained its shape in both experiments shows us that both kinds of substances are incorporated into the tiniest parts of the bone structure.
As in all support and connective tissues, the most important task in terms of function in bone tissue falls to the main substance of the tissue and all the qualities sought in the tissue are provided by the main substance. The basic substance of the bone tissue consists of collagen fibers extending in certain directions for function and the intermediate material that fills these fibers and connects them to each other. This intermediate contains various inorganic salts, the proportions of which we have shown above. These salts are in a state of dispersion in a liquid substance containing albumin. We can compare the structure of bone tissue with that of reinforced concrete construction. Collagen fibers are iron rods used in construction, while the intermediate acts as concrete filling the iron rods. It is to provide the essential material, the qualities of the elements, the relationship between them and the structure, shape of the tissue and the desired properties from the bones. Bone tissue is hard, but at the same time retains some elasticity. This is very important in terms of bone strength and resistance to various effects. If we compare bone with wood in terms of resistance, the resistance of bone against pressure is 8 times higher than that of wood, and its tensile strength is 3 times higher.
Bone cells that make up the main substance made of collagen fibers and the material that fills between them are located in tiny spaces between the main substance. These cavities connect with each other through tiny channels and the extensions of the cells are inserted into these channels. In this way, neighboring cells combine with each other to form a syncytium. This syncytium, which is in the form of a dense network of cells, is present all over the bone. The growth of the bone, its metabolism, the formation of the essential substance, and the amounts and proportions of the various inorganic salts in the intermediate, that is, the events that provide the whole existence and qualities of the bone, all depend on the survival and normal functioning of the bone cells. Bone tissue in terms of structure, according to the condition of the collagen fibers that make up the most important structural elements of the bone tissue. It is divided into two basic groups as fibrinous and lamellar.
In fibrinous bone tissue, collagen fibers extend in thick beams in various directions, sometimes crossing each other, sometimes parallel. Between these beams, which are stuck together with the intermediate containing inorganic salts, there are bone cells and vessels feeding the bone. Collagen fiber beams on the outer surface of the bone are elongated with the fibers in the periosteum covering the bone. For the passage of vessels, thin channels that frequently anastomose with each other are seen. This type of bone tissue is seen mainly in embryonal life and young ages in high-class animals and humans. 3rd-4th in humans. The structure of the bones changes gradually until the age and takes the form of a more technically perfect lamellar structure. In adult humans, the fibrinous structure is seen only in the bony parts of the tendons, muscles, and ligaments. In some lower animals, the fibrinous structure of the bones remains for life.
The basic substance in lamellar bone tissue, namely collagen fibers and the intermediate that binds them together, form thin lamellae with a thickness of 4.5-11 microns. Within these lamellae, collagen fibers are elongated parallel to each other in an inclined state. In long bones, these lamellae are arranged concentrically around a canal called the Haversian canal, which contains vessels and nerves. In this way, 3–8 lamellae wrap around each other from the outside, forming a thin wall surrounding the Haversian canal. Since the collagen fibers in various lamellae have directions and degrees of inclination with respect to the canal axis, crosses occur between the collagen fibers of the various lamellae that surround each other. We can compare the thin wall made of several lamellae surrounding the Haversian canal with a wall made of thin laths crossing each other. In this way, provided that less material is consumed, a more robust and more resistant structure against forces from various directions is obtained at the same time. Small spaces between the lamellae contain bone cells. These cavities are connected with each other on the one hand and with the Haversian canal on the other by means of very thin canaliculi. The protoplasm extensions of the cells are inserted into these canaliculi. In this way, the cells establish a connection with the vessels and nerves passing through the Haversian canal, on the one hand, and among themselves, on the other. The Haversian canal, together with the surrounding lamellae, forms the Haversian column or osteon. Osteons are several centimeters in length and vary widely in various bones and parts of the same bone. Their channels vary between 100 and 500 microns, depending on the width of the Haversian canal and the number of lamellae surrounding the canal. In long bones, the positions of osteons are parallel to the bone axis. Collagen fibers that participate in the structure of the lamellae do not go out of the osteons and do not interfere with the periosteum. Here, the connection between the bone tissue and the periosteum is provided by fibers called Sharpey’s fibers mixed with the bone tissue on the one hand and the periosteum on the other.
Between the osteons, lamellae are seen randomly extending in various directions. These lamellae are called interstitial lamellae. Interstitial lamellae are the remnants of osteons that are partially resorbed during the development of bone tissue and subsequently during continuous changes. These fill the gaps between the haversian columns (osteon). In addition, lamellae suitable for the shape of the bone and parallel to each other are seen near the outer surface of the bones and the inner surface facing the spaces in the long bones. These are called outer and inner lamellae (basic lamellae). There are channels for the vessels coming from the periosteum, extending into the bone in various directions by piercing the main lamellae, and these channels are called Volkmann channels. Volkmann canals are not surrounded by lamellae like Haversian canals. Each Volkmann canal joins with several Haversian canals, and in this way the veins passing through the Volkmann canal supply the fine veins within the Haversian canals with blood. The osteons, which take place in this shape and structure of the bone tissue, are mainly seen in the hard shell parts of the bones (substantia compacta). The substantia compacta is particularly thick in the middle of the long bones. At the ends of long bones and short bones, the substantia compacta only covers the outer surface of the bone in a thin layer. The bone tissue under this layer shows a different structure. Here, there are no osteons that are close to each other, arranged regularly and extending in a certain direction, and therefore the macroscopic appearance of the substantia spongiosa is different. As the name suggests, the structure of the substantia spongiosa is similar to the structure of sponge tissue, and here we see cavities of various sizes, but easily visible, bounded by thin bony partitions of varying state. The cavities contain red marrow (medulla osseum rubra) in living things and fresh cadavers. The cavities are connected to each other through the canaliculi between them. Thin bone partitions that delimit the spaces are made of several lamellae stuck together. Although the conditions of these compartments seem random and irregular at first glance. Thorough investigations on the spongiosa have revealed that the states of these thin bone compartments are arranged according to a certain system and that this system is arranged according to the function of the bone.
Bones are constantly under the influence of two major forces. One of them is the weight and the other is the pulling force of the muscles attached to the bones. The effect of these forces is distributed in the bone, following certain directions. We can show the direction of action of forces with lines. These lines are called bone trajectors. Studies have shown that in the examination of the spongiosa structure of the head and neck parts of the human thigh bone, the bone partitions limiting the spaces here and the states of the thin bone fragments extending inside the thin columnar spaces are adjusted according to the trajectors we have described above, that is, the direction of the force effect. The state of the partitions limiting the spaces has been adjusted according to the directions in which the pressure and tensile force are most effective. Thin pieces of bone extending between and connecting the chambers support the chambers and reinforce their condition. With the application of this system, it has been possible to ensure that the bone is more durable with less material consumption in the human bone as in the machines. If the femur (thigh bone) were made of a continuous and compact tissue, we would not gain much in terms of strength and durability. However, we would have lost a lot in terms of material consumption and the increase in the weight of the bone.
Periosteum consists of two layers that differ from each other in terms of structure and function. The outer layer is made of solid fibrous connective tissue (stratum fibrosum) and is continued at the bone ends by the fibrous layer of the joint capsule that surrounds the joints. Made of soft connective tissue. The layer rich in vessels and nerves is called the cambium layer. During the development of the bone, there are osteoblasts, the cells that make up the bone tissue in the cambium layer. After ossification is complete, the osteoblasts disappear. However, when new bone tissue needs to be made from the cartilages, osteoblasts reappear in the cambium layer. Therefore, the periosteum plays a very important role in bone regeneration. The vessels in the cambium layer are inserted into the bone tissue through the Volkmann canals and bring blood to the thin veins in the Haversian canals.
Occurrence of Bone Tissue
As explained above, bone tissue takes its origin from embryonal connective tissue. The flat bones that make up the cranium and the outlines of the calvicula develop as connective tissue for a while and then ossify directly. In other bone templates, the embryonal connective tissue first takes the form of cartilage tissue. All bone templates remain in this state for a while, and then ossification of cartilage tissues begins at different times for different bones. The ossification event generally takes a very long time, but for certain bones the onset and outcome times of this event are fairly constant.
Ossification of connective or cartilage tissue does not consist of changing the shape of the existing tissue. On the one hand, bone tissue is formed, on the other hand, existing connective or cartilage tissue is destroyed and resorbed. Cells that form bone tissue and take their origin from mesenchyme cells are called osteoblasts. As a result of the activity of osteoblasts, the main substance called obsteoid is formed and collagen fibrins are formed in this substance. After a while, inorganic salts begin to accumulate in the intermediate between the fibrins. As we said above, in human embryonal life and in the 3rd–4th stage. The structure of bone tissue until the age of fibrin. After that, the state of the fibers changes, lamellae and osteons are formed.
Ossification of bone templates made of cartilage tissue occurs in two ways. In short bone drafts, ossification begins in the interior of the draft. This type of ossification is called enchondrol ossification. In long bones, however, ossification begins primarily from the outer layer of the cartilage framework (perichondral ossification). The bone tissue, which is formed by the activity of osteoblasts in the inner layer of the perichondrium, first becomes thin and surrounds the body of the long bones (diaphysis) from all sides in the form of a cuff. This layer of bone becomes thicker and thicker. After a while, the cartilage tissue begins to resorb with the effect of the cells in the connective tissue, which are inserted into the interior of the draft together with the blood vessels, and thus, spaces are formed in the draft. These primary cavities gradually enlarge and merge with each other, thus forming the marrow cavities in the diaphyses of long bones (cavum medullare). These cavities contain yellow bone marrow (medula osseum flava) in adult humans. With the formation of primary cavities in the cartilage framework, ossification at the borders of these cavities, that is, enchondral ossification, as in short bones, begins.
There is also partial perichondral ossification in short bones. When the bone tissue, which starts from the inside and occurs as a result of enchondrol ossification, approaches the outer surface of the short bones, perichondral ossification begins here, as in the long bones, and a bone layer surrounding the outline is formed.
At the ends of long bones. (epiphysis) ossification points occur separately from the diaphysis. Ossification of the epiphyses begins within the outline. A narrow piece of non-ossified cartilage remains between the growing bone tissue and the ossified diaphysis. Since cartilage cells retain their ability to proliferate and grow whole tissue, this cartilage layer is very important for bone growth. Here, the growing cartilage tissue gradually ossifies from the parts close to the diaphysis and is gradually added to the tissue of the diaphysis. In this way, the longitudinal growth of the bone body and eventually the growth of the whole body is achieved. Therefore, this cartilage layer, located between the diaphysis and the epiphyses, plays a very important role in the growth of the sides and the whole body. If this thin layer of cartilage, called the epiphyseal line or growth line (epiphyseal plate), is destroyed, the growth of that bone is retarded. Therefore, the separation of bones from this line at the end of an accident in children causes significant disability.
The growth of bones in thickness occurs with the activity of osteoblasts in the layer of the periosteum, which shows the feature of continuous division, and the addition of new new bone layers. With the ossification of the epiphyseal lines, the growth of the bone and the whole body ceases. Therefore, the ossification of these lines is early. It prevents the body from growing. Being late causes the body and especially the extremities to grow too much.
During development, the structure of bones changes constantly. On the one hand, while new tissues are made, on the other hand, existing tissues are resorbed and in this way, each bone takes its unique shape at the end. Changes in bone tissue continue in adults as well. However, these changes do not occur in terms of shape and size, but rather in terms of the amount and proportion of various substances in the fine structure of the tissue and the main substance. Since the resorption of bone tissue is high in old age, the bones also undergo some changes in terms of shape and the strength of the bones decreases. Hormones have a great effect on the development of bones.
Thyroid gland and the secretions of the anterior lobe of the pituitary accelerate the growth of bones. The internal secretions of the genital glands inhibit growth. If the effect of these secretions occurs at a normal time and at a normal rate, the growth of the bones and the whole body will be normal. The lack of certain secretions, or the premature or too late effect of the effect, causes various abnormalities in growth.
The shapes of the bones are adjusted according to the tasks they perform and in accordance with the general structure plan of the body. Long bones, in addition to carrying weight, also act as leverage. Short bones form elastic and springy columns and domes by joining together through immobile and less mobile joints. Flat bones form solid walls for the cavities that contain important organs. Neighboring organs, especially muscles, have a great effect on the external appearance of the bones. At the attachment points of the muscles, protrusions and protrusions occur on the bones with the effect of the pulling force. They are given various names according to their shape, such as tuberculum, tuberositas, processus, crista and spina. Vessels and nerves passing over the bone form sulci (grooves) in the bone, and vessels and nerves passing through the bone create holes (foramina).
Classification of Bones:
The human skeleton consists of two parts, the axial and appendicular skeleton. There are a total of 206 bones in the human body. However, this number is not fixed. It may vary according to age.
Number of bones in the axial and appendicular skeleton.
These bones can also be classified according to their shape. Accordingly:
1. Long bones: ossa longa
2. Short bones: ossa brevia
3. Flat bones: ossa plana
4. Irregular bones : ossa appendiculare
5. Sesamoid bones: ossa sesamoidea
1. Long bones (ossa longa): Their length is greater than their width. They are found in the extremities. For example: ulna, femur, tibia, metatarsals etc. Each long bone consists of two ends with an elongated body and mostly articular surfaces. The body part is called the diaphysis and the ends are called the epiphysis.
The epiphyses of a developing bone are completely cartilaginous. As soon as epiphyseal ossification begins, they are separated from the diaphysis by a discus epifisiale. The part of the diaphysis adjacent to the discus epiphysiale is wider than the other parts. This includes the broad marginal development line and newly formed bone. This part is called the metaphysis. Metaphysis and epiphysis are bones in adults.
The diaphysis of a long bone consists of a tube made of compact bone. The space in the middle of it is called the cavitas medullaris. This cavity contains the bone marrow. The epiphysis and metaphyses are made up of irregular bone rods and trabeculae that anastomose between them. This is called cancellous bone. Their surface is covered with a thin layer of compact bone. Articular surfaces are usually covered with hyaline cartilage. The connective tissue membrane called the periosteum covers the surface of the bone.
Periosteum consists of an outer -fibrous- layer and an inner osteogenic layer with excess cells. Periosteum is absent at the ends and articular surfaces of the bone. Periosteum provides nutrition and protection of the bone. When the bone is broken, the osteogenic layer is involved in bone formation again. It also provides attachment of muscles and tendons to the bone. The collagen fibers of the tendon are fanned into the periosteum. Some fibers go further in and pierce the bone wall. The inner surfaces of compact bones are covered with a cellular layer called the endosteum.
2. Short bones (ossa brevia): These are bones that are more or less close to each other in thickness, length and width. Numerous in hands and feet. They mainly consist of cancellous bone and a thin layer of compact bone tissue surrounding it. They contain bone marrow. Except for the articular surfaces, they are covered with periosteum.
3. Flat bones (ossa plana): Costas, sternum, scapula and skull bones are included in this group. They are usually in the form of a thin and curved layer. They are made of cancellous bone between the outer and inner two compact layers. They contain bone marrow. The spongy layer in the skull bones is specifically called the diploe. There are many vein canals in Diploe. Some flat bones (lacrimal) consist of only one sheet of compact bone. Articular surfaces are covered with cartilage or fibrous tissue.
4. Irregular bones (ossa appendiculare): They are irregularly shaped, which do not fit any of the above classification. Some skull bones, vertebrae, os coxsa fall into this group. They are mostly made of cancellous bone surrounded by a compact layer. However, many parts are only compact bone. Some of these contain air-filled sinuses. These are specifically called pneumatic bones. For example: maxilla, temporal, frontal, ethmoid bones.
5.Sesamoid bones: The short type bones embedded in the tendon or joint capsule of the hand and foot are called sesamoid bones. Some can easily change the tendon pull angle, such as the patella. Others are the size of sesame or lentils.
Auxiliary bones: These may not be found in every person. They can be short and flat type. Some types of sesamoid bones and bone fragments that are not fused with the epiphysis for any reason are called this. For example: like my os trigon. These types of bones are clinically important because they can be mistaken for fractures on radiograms.
Structures on the Bone Surface
Often there is a processus articularis attached to the bone by a collum. Sometimes, bite-shaped projections called condyls are encountered. The condylars contain the articular surface. The articular surface is covered with hyaline cartilage. Bite-shaped projections that do not contain an articular surface are called epiconyl. Other types of projections that vary greatly in shape and size are called processus, trochanter, tuberositas, protuberantia, tuberculum and spina. Line-shaped projections are called arcus, crista or linea, and line-shaped grooves are called sulcus. The large jaws of the pits are called the fovea or foveola. The large space inside a bone is called the sinus or antrum, and the hole that opens the space inside the bone is called the foramen or ostium. In addition, terms such as canalis, hiatus, aditus, aqueductus are used to describe the different shaped openings in the bone. The flat areas on the bone are called facies, the margins are called margo. Slit or notched parts are called incisura, fissura.
Vessels and Nerves of Bone
Bones have a rich vascular system. Long bones are fed by the following types of vessels.
One or more posterior, nutricia pass through the holes called foramen nutricia in the compact layer of the diaphysis and divide into branches that run longitudinally up to the metaphysis. It nourishes the bone and marrow. Foramen nutrium are found in all bones.
Numerous periosteal vascular branches supply the compact bone. Metaphyseal or epiphyseal vessels, which arise mainly from the arteries supplying the joint, pierce the compact layer and supply the cancellous bone. In bone, the metaphyseal and epiphyseal vessels are separated from their surroundings by a cartilaginous lamina. All these vein types we have mentioned are very important in the nutrition of the development line. If there is a disorder in the blood supply, there will definitely be a developmental disorder.
Epiphyseal and metaphyseal arteries anastomose between them. Infections that come with blood vessels are mostly located at the ends of the bones. The blood flow of the mature bones goes from the inside out. The blood first flows from the medullary artery system to the substantia compacta capillaries and then outwards to the periosteal capillaries. Nerve fibers enter the bone along with blood vessels. Most of these fibers are vasomotor and some are sensory fibers. Nerve fibers terminate in the periosteum and outer layer of vessels. Some of the sensory fibers are pain fibers. The periosteum is extremely sensitive to tearing and stretching.
If the compact layer is entered without anesthesia, an ache and distressing sensation occurs. Entering the spongious bone causes extreme pain. Fractures are extremely painful. Injecting anesthetic into the fracture surfaces is of great benefit in relieving pain.
Painful in a tumor or infection that causes the bone to enlarge. Pain in the bone is felt locally and directly at the stimulation site. However, it is common when the pain radiates or recedes. For example; A pain in the femoral diaphysis can be felt in the lower thigh and knee. There are nerve endings that carry position sense in the periosteum.
Bone Architecture: Architecture ossea
Bones are constantly under the influence of two important factors. One of them is weight, and the other is the pulling force of the muscles attached to it.
The effects of these forces are dispersed in the bone, following certain directions. We can show the direction of action of these forces with lines. These lines are called trajectors.
Anatomists examined the head and neck of the human femur bone and proved that the thin bone is ordered from there according to the direction of impact.
The state of the chambers limiting the cavities in the bone is adjusted towards the directions in which the pressure and tensile forces are most effective. In the regions where the two bones articulate, it is seen on X-ray films that the trajectors in one bone continue in the same way in the adjacent bone.
Variations
Bones vary according to race, age and sex, as well as from person to person.
Female bones are often lighter and smaller. Because they complete their development earlier. Muscular protrusions are more specific in males.
Children’s bones are very flexible. As soon as it is broken, its breaking is like a sapling stick. Their mature bones break like dry wood.
The majority of individual variations pertain to the size, shape and weight of bones. The degree of development of the muscles affects the shape of the bone. If the muscles are strong, the protrusions of the bone are also evident, for example; mandibula’nın prosessus coronoideus’u çiğneme kasları tam geliştiği zaman belirli olur. Kemik yüzeyindeki kabarıntılı veya hatlar gibi sekonder işaretler puberte zamanında belirlenmeye başlar. Bunlar daha çok tendonların tutunduğu yerlerdir. For example; linea aspera bu devirde daha çok kalınlaşır. Eğer ekstremite de bir kemik çıkarılırsa veya doğmalık olarak yoksa komşu kemik hipertrofıye uğrar. For example; fibula çıkarılırsa tibia hipertrofiye uğrar. Tersi olarak kemik üzerine kas faaliyetleri ortadan kalkar veya azalırsa kemik atrofıye uğrar. Felçli hastalarda ve atellerde bu olay görülür. Kemiğin hem organik hem inorganik maddeleri yavaş yavaş kaybolur.
Eğer herhangi bir nedenle eklem kıkırdağını kaybederse bu defa kemik yüzeyi çok sert ve cilalı bir şekil gösterir.
Kemiğin Sağlığı
1. Kemiklerde organik kısmın inorganik kısma göre oranı yaşla birlikte değişir. Çocukluk döneminde organik kısım daha fazladır. Raşitizm ve osteomalazi gibi bazı metabolik bozukluklarda kemik matriksinde kalsifikasyon yetersiz kalır. Kalsiyum kemiğe sertlik kazardırdığı için, kalsifiye olmamış sahalar özellikle fazla ağırlık taşıyan kemiklerde eğilir ve ilerleyici deformitelere neden olur. For example; raşitizm sonucu bacakların yay şeklinde bükülmesi gibi.
2.Kırıklar, günlük hareketlerinde daha dikkatsiz ve daha sert oldukları için çocuklarda gelişkinlere göre fazla oranda görülür. Bereket fidan çubuğu şeklindeki bu kırıklar çabuk iyileşirler. Ancak epifiz diski kırıkları çok önemlidir. Çünkü bu kırıkları iyileşmesi sonucu diafiz ve epifiz daha erken kaynaşacağı için sonuçta kemiğin kısa kalmasına neden olabilir, örneğin; ön kolda radius alt epifızin kırığında radius kısa kalacağından ve ulna boyunca büyümeye devam edeceğinden elin radial devıasyonu gibi bir şekil bozukluğu ortaya çıkabilir. Çocuklarda ve gençlerde epifizlerin diafize birleşmemesi olgusundan tedavi amaçlarıyla yararlanılabilir. For example; diz epifiz diskinin diafizle bağlantısını engelleyecek şekilde yerleştirilen bir metal plak ekstremitenin boyunca uzamasını durdurur. Bu yolla kısa kalmış diğer ekstremitenin boyunun, plak yerleştirilmiş normal ekstremite boyuna ulaşması sağlanabilir.
3.Yaşlılıkta kemiğin hem organik, hem inorganik kısmı azalacağından (osteoporozis) elastiklik kaybolur ve kemikler kolay kırılır bir duruma gelirler. Osteoporozise yaşlı kadınlarda, erkeklere oranla daha sık rastlanır.
Wishing you a healthy day…
Specialist Dr.Ali AYYILDIZ – Veterinarian – Human Anatomy Specialist Dr.(Ph.D.)
