Osteoarthritis (from the Greek. osteon - bone and arthron - joint) - chronic diseases of joints, characterized by degenerative-dystrophic changes of all its tissues (including bone, articular cartilage, ligaments, tendons endings and other soft tissues). Earlier this disease is called osteoarthritis, however, correct term osteoarthritis, as it reflects the nature of the lesion.
There are primary and secondary osteoarthritis. Primary osteoporosis occur independently old or old age, and for no apparent reason in relatively young (Hesse O.). Are affected in varying degrees, all of the joints; in large joints (especially in the lower extremities) changes generally expressed more sharply than in small ones. To primary and are rarely observed forms of O. arising in athletes and athletes due to overload or over-training individual joints.
Secondary osteoarthritis are the consequences of the previous joint diseases traumatic, inflammatory or another etiology. In this regard, in secondary O. often there are isolated lesions mostly a particular joint. Multiple lesions result transferred common diseases (rheumatism, influenza, intoxication and other). However, in these cases, along with uniform defeat all the joints larger ones due to the increased functional load may be more modified.
Differential diagnosis between primary and secondary osteoarthritis can be conducted on the basis of careful study of history, especially the nature and course of previous diseases. In practical work differential diagnosis often encounters the well-known problems.
Recognition Acting mainly based on the data of x-ray studies. The main method of investigation is x-ray of the joint is straight and lateral projections. Sometimes to recognize some of the diseases of joints is almost enough snapshot only one projection. Usually radiograph in the second projection, as tomography or stereolithography could be a valuable help to clarify some details, and the nature and location of pathological changes in tissues of the joints. So, for example, tomograms, reflecting the different layers joint tissue, can detect changes in the articular cartilage and soft tissues, accompanied by calcification and Otomi small bony prominences and "bills". Stereolithography give a clear picture about intra - or extra-articular localization calcified foci and intracavitary location necrotic or calcified areas of articular cartilage. In the choice of auxiliary methods of research (tomography, stereolithography) should be guided first of all data conventional radiography and individual features of the clinical picture of the disease.
X-ray picture of osteoarthritis largely a reflection of pathological changes of the joints, most dramatically expressed in the articular cartilage. Along with decreasing thickness of the articular cartilage (due to its atrophy) is razvlechenie its main substance, fat and vacuolar degeneration of cartilage cells, accompanied by rejection in the joint cavity pieces degenerated and nekrotizirovannah cartilage substances. As a result, the articular surface of the epiphyses cracks, Uzury and more or less large defects cartilage cover. Simultaneously marked focal lime deposits in the basic layer of articular cartilage, and therefore the frontier zone of calcification (the so-called bone reflex record cancellous epiphysis) hardens and thickens. Especially intensive calcification of the base layer of the articular cartilage in peripheral areas, respectively places of attachment of joint capsule and ligaments to the bone.
Calcified cartilaginous parts are further subject to ossify, resulting in the formation of the regional bone growth, the so-called bone beak, spikes, ledges, and other Such degenerative-dystrophic changes in the cartilaginous elements, accompanied by calcification of the articular cartilage and cause his thinning and, consequently, the narrowing of the x-ray of the joint space. Due to the fact that these processes are quite uneven in different parts of the articular surface, edges of epiphysis glenoid acquire in the x-ray image Jaggy and the gum-forepart is missing.
Bone epiphysis also undergo degenerative changes, expressed in varying degrees of osteoporosis, against which the x-ray visible racemose education (Fig. 1 and 2) from subtle to fairly large, clearly emerging in CT. Along with osteoporosis in advanced stages, especially at the secondary osteoarthritis, are often observed and atrophic changes in the articular ends of the bones. All these changes cartilage and bone of the epiphyses are accompanied by the deposition of salts of lime in the soft tissues of the places of attachment of the joint capsule, ligaments, tendons, and other Such phenomena, combined with pronounced changes in the articular cartilage, leading to the flattening and deformation articular head and depression and disturbance of the function of the joint. Calcified tissues, bone bills, spurs and other calcified education are microtransactions damage, accompanied by bleeding and reactive inflammation, which in turn strengthens degenerative-dystrophic processes articular elements and their subsequent calcification. The study of the series of x-rays produced in different periods of the disease, allows to visualise the development dynamics of the Acting, especially the phenomenon of increasing the deformation and calcification joint tissue.
Clinic and treatment of osteoarthritis - see Arthrosis.

Fig. 1. Secondary osteoarthritis of the left knee after suffering a nonspecific arthritis. Articular gap narrowed. Subchondral area epiphyses sealed. On the background of osteoporosis visible kistevidnyi education. The epiphyses deformed.
Fig. 2. Primary osteoarthritis of the right shoulder. Pronounced narrowing of the joint space. The contours of the joint edges bones underlined. Kistevidnyi education in the humeral head, foci of calcification of soft tissues.