Nearthrosis

Description:

Nearthrosis (pseudoarthrosis; a synonym a pseudoarthrosis) — disturbance of a continuity of a bone with development unusual for the department of mobility given it.

Nearthrosis symptoms:

The crack between the bone fragments forming a nearthrosis is filled not with a bone callosity, but connecting fabric. At long existence of a nearthrosis mobility in it can increase, the neoarthrosis (a new joint) in which there are a capsule, the joint cavity containing synovial fluid is formed, and the jointed ends of a bone are covered with a cartilage.

Characteristic symptom of nearthroses — pathological mobility of a bone in its unusual department, a thicket throughout a diaphysis. Degree of this mobility is various: from scarcely noticeable before movements with a big amplitude. In some cases the clinical symptomatology can be poorly expressed or be absent (for example, at a nearthrosis of one bone of a two-bone segment). Axial loading during walking at a nearthrosis of the lower extremity as a rule causes pain. Inborn nearthroses, for example bones of the lower extremities, most often shins, are shown when the child starts walking. Big pathological mobility is characteristic of them, than at the acquired nearthroses.

At establishment of the diagnosis are guided in addition to clinical data, by the term necessary normal for an union of this type of a change. After the expiration of this term speak about in a slowed-up way the growing together or not accrete change, and later the doubled or bigger term — about a nearthrosis. Crucial importance for diagnosis of a nearthrosis has X-ray inspection. Roentgenograms carry out surely in two mutually perpendicular projections, sometimes use additional slanting projections, and also a tomography. Main radiological signs of a nearthrosis: lack of the bone callosity connecting the ends of both fragments; curve and smoothing of the ends of fragments or their conical shape (atrophic nearthrosis); fusion of a marrowy cavity on the ends of fragments (development of a switching plate). Quite often the end of one fragment has the hemispherical form and reminds an articular head, and the end of another will be bent like a joint hollow. At the same time on roentgenograms the joint crack (neoarthrosis) clearly is visible. A thickening of bone fragments in a nearthrosis crack zone, uneven contours of the crack, its small width are characteristic of a hypertrophic nearthrosis. For assessment of intensity of processes of an osteogenesis in a zone of a nearthrosis use a radionuclide research.

Nearthrosis reasons:

Distinguish the inborn and acquired nearthroses. It is considered that pre-natal disturbance of an osteogenesis is the cornerstone of inborn nearthroses. The acquired nearthroses in most cases — the complication of fractures of bones caused by disturbance of an union of fragments. The acquired nearthroses are subdivided on hypertrophic, atrophic and normotrofichesky. For formation of a nearthrosis considerable discrepancy of bone fragments after their reposition, the insufficient immobilization or its premature termination, excessively early load of the damaged extremity segment, suppuration in a change zone, local disturbance of blood supply of bone fragments matter. Less often a nearthrosis osteotomies are formed after orthopedic bone operations, for example, and at pathological changes.

Treatment of the Nearthrosis:

Treatment of a nearthrosis, generally operational also depends on type and localization of a nearthrosis. Various methods of an osteosynthesis, as a rule in combination with bone plastics are used.