Osteodystrophy

Osteodystrophy - pathological process in the bone tissue, which is based on local metabolism. In osteodystrophy is a reorganization of the bone structure, reflected mainly in increased resorption of bone items and replacement of fibrous tissue. Consequently osteodystrophy can be accompanied by deformation of the bones, pathological fractures, the appearance of zones of perestroika (see Looser zone of perestroika). Osteodystrophy develops in human nutrition in connection with diseases of the digestive system, beriberi, General metabolism disorders, poisoning with chemical substances, endocrine diseases.
For diagnosis osteodystrophies need an x-ray. The main x-ray characteristic of most forms osteodystrophies is the rebuilding of bone structure is osteoporosis (see). When fibrous osteodystrophies the x-ray revealed swelling of the affected Department bones, the emergence krupneishii patterns, thinning of the cortical layer, the substitution of conventional patterns many cysts, delimited bone partitions.

Osteodystrophy (osteodystrophia; from the Greek. osteon - bone + dystrophy) - pathological changes in bone tissue, coming as a result of violations of interstitial metabolism. In view of the many and varied conditions of occurrence of these violations to osteodystrophies carry many diseases and conditions of the skeletal system. The feature is the contrast inflammatory and neoplasticeskih processes, which is of great practical importance for recognition. General morphological basis osteodystrophies (see below) is the rebuilding of bone structure, reflected in most cases excessive in comparison with the rate of resorption of bone cells and formation of new bone is different from predshestvovali original structural features.
Certain types osteodystrophies (intoxication fluorine, bismuth and lead to kidney failure in adults, idiopathic hypercalcemia) is characterized by extremely strong formation of bone substance.
GBS connection with reorganization of the bones again arise characteristic deformation (bending, flattening, partial atrophy, and sometimes pathological fractures). When the number of O. there is a local rebuilding of bone tissue, leading to violation of the integrity of the bone with education Looser zone of perestroika (see).
There are the well-known problems of delimitation Acting from osteodysplastic (see) because of their remarkable similarity between them. In practical terms, is much more important to have in mind not so much the differences Acting from osteodysplastic many differences between both groups of pathological processes from diseases other nature (primarily inflammatory and tumor). True osteodistrofije should be considered processes caused by: 1) toxic factors with long-term intake (professional and home) of certain chemicals (toxic poisoning); 2) nutritional disorders (intestinal, liver, gallbladder, gastric, pancreatic O., avitaminosis, hypervitaminosis a); 3) endocrine disorders (giperparatireoidizm, thyroid, pituitary, O.); 4) internal diseases and common metabolic disorders (nephrogenic osteopathy). To these diseases attach also angioneuroticeski osteodystrophies (violations of neurotrophic character).
For the vast majority of these diseases are largely common are the similarities of the mechanism of their development, the long duration of the course, the slow growth of morphological and clinical phenomena. Angioneuroticeski same disorders usually characterized by the severity of current and clearly marked transient nature of the changes (so-called acute bone atrophy of sodeca); from this point of view they should be considered separately (see the Bone).
When most osteodystrophy clearly, the relationship between changes in bone skeleton with the General condition of the body or with diseases other anatomical and physiological systems.
Pathological anatomy. When osteodistrofia caused by diseases of the liver, intestines, major changes bones are predominant osteoporosis (see). In many cases, developing osteomalacia (see)when absorbable
the bone structure is delayed osteoid. When the so-called hungry osteopathy is increased resorption of bone, providing income from the bones into the blood calcium, necessary for maintenance of ionic balance. Resorption of bone substance occurring in both of its components - protein and mineral, not compensated by building new bone structures. In persons with incomplete skeletal growth hungry osteopathy may be complicated by the disorder.
In avitaminosis And violated encontrarnos and periosteal bone formation, which affects mainly in the growing organisms. Decreases cell proliferation germ cartilaginous plates, violated the correctness of their location in the columns, reduced bone formation of beams of the metaphysis, they are not longitudinal to the GSP bones as normal and parallel to sprout records. Last prematurely closed, leading to stunting. When hypervitaminosis And observed giperostos in the field of divisov long bones.
With a lack of vitamin C had been a violation of collagen and, in particular, bone formation. Resorption of bone tissue is not compensated by the formation of new bone substance is developing osteoporosis. In adults osteoporosis is most pronounced at the border rib cartilage and bony part, explains multiple fractures of the ribs with a shift of the sternum. Microscopically mainly in the field of germ zones in persons with unfinished growth of bone of the beams of rare, thin, often seen their fragments. If the fracture is thinned cortical layer that separates the epiphysis from diaphysis. In young children in scurvy in these areas there are massive hemorrhage. In interosseous spaces develops nizhnovreklama osteogenic fabric, however, maturing it to the bone is rather imperfect.
Changes in the bones when the thyroid goiter caused by a sharp intensification of metabolic processes, including intraosseous, and expressed enhanced rebuilding of bone. Young organisms hyperthyroidism causes acceleration of bone growth. In some cases, over time, can develop expressed osteoporosis (see). PA soil his arise pathological fractures. In cases of hyperthyroidism, accompanied by a lack of vitamin D, bone substance has the character Stevenage that entails complications of the disorder. Microscopically strengthening of perestroika bones impact osteoclastic resorption, increasing number of pasting lines, which creates a mosaic pattern of bone beams. Intercostals space filled fibromyomas osteogenic cloth. Often these changes are very reminiscent of the parathyroid osteodystrophy (see) and therefore one microscopic examination sometimes difficult to differentiate these diseases. In case of lack of vitamin D, the need in which thyrotoxicosis increased, on the edges of bone structures and interosseous spaces appears osteoid. Hypothyroidism caused by congenital hypoplasia (aplasia, hypoplasia) thyroid cancer, slowing down processes age of perestroika bones. In cortical bone is poorly expressed Astondoa structure, to deep age remains a large number of inset (interstitial) plates. These bones are less strong, they observed microfractures, there deformation (see Osteochondropathy). Germ cartilaginous plates prematurely closed, bone growth slowed and stopped that causes dwarfism.


From osteodystrophy due to toxic effects of the greatest importance osteodystrophies from the effects of lead, fluorine. Most of replacing poisoning salts of lead affects bone children. Lead salts are deposited in the bone substance is growing bones, especially in the area of pre-calcification and adjacent metafizare region, accompanied by osteosclerosis (Fig. 1). Especially sharply pronounced osteosclerosis in the bones, intensively growing in the period of lead exposure on the body. The removal of lead salts from the body is hampered because of salt entering the blood of biodegradable bone structures, again recorded novoobrazovaniya bone substance. Intoxicated with fluorine see the osteosclerosis (see) or rarefication bones with simultaneous periosteal hyperostosis (Fig. 2). Sometimes bone substance has the character of osteoid. In the periosteum and ligaments see the accumulation of salts, lime coming obviously from the bones when they are ratifikatsii. The clinical picture osteodystrophies extremely diversified both in public and private symptoms. In clinical practice the most convincing signs of a majority of O. detected by x-ray.
The dominant symptom in x-ray picture of many osteodystrophies processes (rickets, renal osteodystrophy, hypothyroidism, parathyroid O., osteomalacia) is osteoporosis (Fig. 3). Very indicative sclerotic reaction is found in many of the bones of the skeleton, such as fluorosis (Fig. 4).
Find radiographically violations epigastralna growth are found for diseases such as rickets (Fig. 5), children scurvy, renal O., Hypo - and tereos, pituitary dwarfism. These changes can result resorption zone prior calcification, for example in renal Acting or, on the contrary, braking its resorption at children's scurvy (Fig. 6). X-ray picture of giperostos most sharply expressed in akromegalia. Focal decrease of bone density (Fig. 7) in many bones found in such systemic diseases as xanthomatose, chlamydia. Zone of perestroika Looser arise in rickets, neurotrophic disorders, parathyroid osteodystrophies. In General the nature of such pathological processes, as O., morphological and clinical manifestations of disease can develop only in a separate bones.

Fig. 1. The osteosclerosis in metafizare area when lead intoxication.
Fig. 2. Ratifikacija and periosteal giperostos tubular bones intoxicated with fluorine.
Fig. 3. Osteoporosis and deformation of the femoral bone in renal osteodystrophies.
Fig. 4. The osteosclerosis pelvic bones with fluorosis.
Fig. 5. Resorption zone prior calcification in rickets with the expansion of the so-called rachitic zone.
Fig. 6. Braking resorption zone prior calcification at children's scurvy (the scheme of x-rays).
Fig. 7. Focal depression of the skull bones when xanthomatose.