Object: the limited contact multiplanar fixation of diaphyseal fractures of the shin bones. Aim: theoretically substantiate and optimize the method of limited contact multiplanar osteosynthesis of diaphyseal fractures of the shin bones. Methods: theoretical, conceptual modeling, mathematical modeling (finite element method), roentgenologic, clinical, statistical. The concept of a limited contact multiplanar osteosynthesis in tibia fractures was improved, the methodology of its implementation was elaborated. On the basis of this concept, a new method of surgical treatment of fractures of shin bones was developed and a device for fixation of bone fragments has been refined. The quantities of fragments' micromotion were obtained at the models of transverse, oblique and comminuted fractures of the tibia diaphysis after various kinds of osteosynthesis. In the case of transverse fracture improved device for fixation of bone fragments allows large axial displacement of fragments (0.0026-0.2903 mm) under axial load than full-contact plate (0.0023-0.2395 mm). The reduction of micromotion of fragments after preliminary stabilization of oblique and comminuted fractures of the tibia using one or two reposition screws was proved. There was for the device for fixation of bone fragments - from 0.0019 to 0.0516 mm, for full-contact plate - from 0.0041 to 0.0675 mm. Under the action of flexion force the fixating device of bone fragments provides them rigid fixation also. New knowledge of the interactions in the system "fixating device - fragments" was obtained. It was proved that the fixing device of bone fragments provides multidirectional micromotion of fragments. The advantage of multiplanar fixation over a single-planar fixation for fractures of the shin bone was provides theoretically and experimentally confirmed. Status stress of plate of bone fragments was studied. The dependence of stress on the fixing device design, the characteristics of the fracture, the load was analyzed. Studies was shown that fixation of transverse fractures with a device for fixation of bone fragments provides less stress the central part of the bones (0,44017·107 Pa) even in the fragment fixation with three screws than the contact plate (0,62752·107 Pa). Tension plates, screws, bone fragments after fixation of comminuted fractures using reposition screws and device for fixation of bone fragments was smaller (0,11612·109 Pa) as compared with the results obtained by employing the full contact plate (0,13386·109 Pa). This creates optimal conditions for reparative regeneration. The received information is important for preoperative planning design retainer. The feasibility of a differentiated application of the device for fixing bone fragments to limited contact multiplanar osteosynthesis for fractures of the shin bone was substantiated. Clinically on examples of different fractures of shin bones using improved apparatus for fixing bone fragments high efficiency developed method of limited contact multiplanar osteosynthesis was proved. On the basis of the proposed principles of construction of devices for limited contact multiplanar osteosynthesis original multifunctional fixing devises for osteosynthesis of diaphyseal fractures of shin bones was improved. The advanced fixing devises that allows a stable osteosynthesis of diaphyseal fractures of shin bones of any complexity was offered for practical health. Creating of stable system "device - bone" allows avoid postoperative immobilization, accelerate and optimize the rehabilitation period. Opportunity to choose the optimal design, micromotion fragments and its regulation can control the process of bone repair, to determine treatment strategy that improves the quality of life of patients, reducing the duration of their disability. For the first time an opportunity to reduce the number of nonunion fragments after fractures of shin bones. For the first time an opportunity to reduce the number of nonunion fragments after fractures of shin bones. Improved device for fixation of bone fragments for limited contact multiplanar osteosynthesis allows to optimize choice of design for a particular fracture, provides better recovery of the anatomy and function of the damaged segment without external immobilization. Results of the study are introduced into clinical practice Gorlovska city hospital № 2, SI "Dnepropetrovsk sixth clinical hospital", Torez central city hospital, Drohobych city hospital № 1, Chervonograd central city hospital, Torchin district hospital, Kamenka-Bug central district hospital, Korosten central city hospital, Bug central district hospital. Traumatology and orthopaedics.
