X-ray symptoms and skeletal syndrome

Pathological processes that develop in the musculoskeletal system lead to various and highly polymorphic radiographic manifestations. However, on the one hand, the same diseases, depending on the individual characteristics of the patient and the stage of the disease, can cause various symptoms, and on the other - the pathological states, which are opposite in nature and prognosis, are sometimes accompanied by very similar changes. In this regard, assess the radiographic data should only be taken into account the clinical picture and the results of laboratory studies. It should also be borne in mind that the radiograph showing only the mineralized basis of the bone can be normal in cases of soft tissue damage to the musculoskeletal system. As a consequence, during the course of many diseases, a latent ("X-ray-negative") period is isolated. Such patients need to make other radiation studies - CT, MRI, sonography, osteoscintigraphy.

The main abnormalities observed during X-ray examination can be grouped as follows:

1. changes in the position, shape and size of bones;
2. changes in the surface of bones (their contours on radiographs);
3. changes in bone structure:
   • violation of the integrity of bone beams;
   • restructuring of the bone structure;
   • osteolysis and osteonecrosis;
   • destruction and sequestration of bone tissue;
4. changes in the x-ray joint space.

The first group of signs almost does not need explanations. Changes in the position of the bones can be both an anomaly of development, and a consequence of fractures and dislocations. The change in the normal shape of the bone occurs with developmental abnormalities or occurs due to a decrease in bone strength (with vitamin deficiency, bone demineralization, etc.). To change the value of bone leads to its destruction or neoplasm. Thickening of the bone is usually called hyperostosis. It is formed as a result of increased functional load or excessive overgrowth and ossification of the periosteum in disorders of blood circulation, intoxications, inflammatory lesions. Uniform reduction of bone occurs with its underdevelopment or atrophy. The cause of atrophy is most often the limitations of the locomotor function of the skeleton and neurodystrophic disorders.

Changes in the external surface of the bone are observed during the destruction of the cortical layer of inflammatory or tumor origin. In addition, the bones may have protrusions associated with developmental disorders (exostoses) or inflammatory process (osteophytes), but most often changes in bone contours are due to structural changes in the periosteum.

Normally, the periosteum is not visible on radiographs, but in pathological conditions it often calcifies and ossifies. Depending on the nature of the process (inflammatory or non-inflammatory), it is called periostitis or periostosis. In inflammatory lesions, the periosteum moves away from the bone surface with exudate and calcifies. This is the so-called detached periostitis. It has the appearance of a delicate, narrow, discontinuous band located some distance from the contour of the bone. Then the mass of calcified periosteum increases and it sometimes takes the form of fringe from the portier ("fimbriated", or "lacy", periostitis). When bone tumors - sarcomas - ossification of the periosteum, removed from the edges of the neoplasm, - periostitis in the form of a peak, and also ossification along the vessels going from the periosteum to the bone (they are not quite accurately called acicular periostitis) are observed. We add that sonography allows you to detect changes in the volume of the periosteum and the accumulations of blood or pus under it in the "roentgenogenous" period.

Changes in bone structure occur primarily in fractures and are expressed in the break of bone beams and trabeculae : a line appears in the bone, or a gap, a fracture having a different direction and extent. With neurodystrophic lesions, there may be bone resorption, in which the images show an irregular shape of the defect of the bone substance with vague boundaries. Osteonecrosis develops in the bone supply disorder. The necrotic area appears more dense against the background of the surrounding bone. Bone beams in the area of necrosis do not withstand the usual load and are compressed, which leads to bone deformation and an even greater increase in the intensity of its shadow.

In a number of diseases, destruction occurs-the destruction of bone beams and whole bone sites and their replacement with pus, granulations, or tumor tissue. On the roentgenogram, the focus of destruction looks like a bone defect. The contours of fresh destructive foci are uneven, while the edges of long-existing foci become smooth and compact. Destruction often leads to the rejection of bone fragments and their necrosis. Such freely lying and necrotic pieces of bone are called sequesters.

Great importance in X-ray diagnostics has a symptom of restructuring of the bone structure. Under the restructuring of bone is understood any change in bone structure, accompanied by the appearance of a new structure in place of the preceding one. Distinguish between the physiological and pathological restructuring. Physiological refers to all types of changes in bone structure that arise in the process of normal life activity of a person under the influence of certain conditions of work and life, playing sports. Such restructuring takes place in the bone system of a healthy person throughout life. It is characterized by the balancing of the processes of creation and bone resorption. Pathological restructuring can occur as a result of dystrophic, inflammatory and other processes and is usually accompanied by a predominance of processes of resorption or neoplasm of bone elements.

The most common is one of the types of adjustment - osteoporosis (bone thinning). It is expressed in a uniform decrease in the number of bone beams in a unit of bone volume. On roentgenograms, osteoporosis is manifested by increased bone transparency, thinning of the cortex and expansion of the medullary canal, an emphasis on the contours of the cortical layer around the entire bone. In the spongy substance of the epiphyses, metaphyses and in flat bones, a large-plexus bone structure is observed. Osteoporosis can be spotty in nature and can appear as separate small or larger areas of enlightenment or be diffuse and uniform. In terms of length, there are 4 forms of osteoporosis: local, regional, widespread and systemic. Local osteoporosis is a limited area of rarefaction of the bone structure: this is usually the initial manifestation of bone destruction. Regional is called osteoporosis, which captures the whole anatomical region. As a rule, the rarefaction of the bone structure is determined at the articular ends of the bones with arthritis. Osteoporosis is common, spreading to all the bones of one limb, which is usually associated with impaired blood circulation or innervation of this limb. Systemic osteoporosis affects the entire skeleton.

Osteosclerosis is defined as a change in bone structure, in which there is an increase in the amount of bone substance per unit bone volume. In the spongy substance, a finely-looped structure is defined up to such that the bone pattern is indistinguishable. In the long bones, there is a thickening of the cortical layer and narrowing of the medullary canal.

Osteosclerosis may be limited or systemic. The latter form is relatively rare: in some congenital diseases (marble disease), poisoning with fluoride compounds (fluorosis). Multiple areas of osteosclerosis in the bones are identified with intoxication with heavy metals, some types of leukemia, deforming osteodystrophy, renal osteodystrophy, osteoblastic metastases of cancer.

The kind of perestroika is the so-called Lozer adjustment zones. They develop in those cases when the normal bone is subjected to excessive stress or the physiological load is applied to the pathologically altered bone (for example, with vitamin deficiency). At the same time, acute aseptic necrosis occurs in the area of overload. Most often, it manifests itself as a transversal or obliquely extending band of enlightenment in the bone, in which the bony beams are no longer visible. If the load is stopped and immobilization is carried out, the periosteum and endostomium produce a semblance of bone callus and a new structure is formed that can withstand the increased load. Otherwise, a real fracture ("stress fracture") may occur.

The change in the x-ray joint gap is a sign of joint damage. Uniform narrowing of the joint gap most often indicates a dystrophic condition of the articular cartilage. Uneven narrowing is observed with arthritis and can be combined with the destruction of the closing plates and the subchondral layer of the jointed bones. In fibrotic ankylosis, the disappearance of the terminal bone plate is determined, and in bone ankylosis - the transition of bone beams from one epiphysis to another.

Not all radiologic symptoms of injuries and diseases of the skeleton are listed above, but it is clear from the foregoing how many diverse and non-standard combinations of them can be observed in real life. Although the X-ray image of the bone seems to be demonstrative and understandable, a good overall clinical preparation and a pedantic analysis of radial semiotics are required to accurately recognize its lesions from the physician.