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Preoperative planning of surgical treatment is an important stage of preparation for surgical treatment in traumatology and orthopaedics, which makes it possible to emphasise the peculiarities of the clinical case, prevent possible problems during surgery and reduce the risks of postoperative complications. The leading method of diagnostics for further planning of surgical treatment nowadays is radiological studies, primarily radiography and computed tomography. The results of radiological studies allow a sufficiently qualitative assessment of the zone of interest, planning of the required degree of correction and placement of fixing metal structures and endoprostheses. At the same time, when planning, the doctor relies mostly on the knowledge of the norms of anatomical relations and structures. And in the case of a multitude of possible treatment options, the doctor relies on his or her own medical experience to make a choice. This article presents a developed generalising methodology of preoperative planning in traumatology-orthopaedics, which includes biomechanical analysis and methods of accumulation and processing of quantitative data of clinical cases along with the usual methods of preoperative planning for doctors. The methodology brings together into a single system the criteria for evaluating the success of treatment by applying three classes of criteria: geometric (anatomical), biomechanical and clinical. The methodology allows the physician to perform biomechanical modelling of the proposed treatment options and quantitatively evaluate them on the basis of comparison of stress-strain states arising in the «bone-implant» system as a result of each of the planned options. The methodology allows to determine successful treatment options and to predict changes in the patient's quality of life after treatment. The presented methodology includes a mechanism for accumulation of quantitative data on clinical cases and quality control of the used biomechanical models.

Deviation of the first toe to the outside, interconnected with the deviation of the first metatarsal bone to the inside, occurs in 46% of patients of the older age group and is called valgus deformity of the first toe. The negative impact of this pathology on the quality of life of patients is the reason for seeking medical help, the gold standard of which is surgical correction, and the basic surgical technique is osteotomy (sawing the bone and fixing its fragments with implants) of the first metatarsal. At the same time, an ideal osteotomy should provide initial stability in the early postoperative period. However, a large number of ways to perform osteotomy, as well as the advantages and disadvantages of each of the surgical techniques, do not allow to consider one of them as the most successful. In this regard, the aim of the work was to develop and validate a biomechanical model of osteotomy of the first metatarsal bone to analyze its stability and reliability depending on the type of osteotomy, the degree of displacement of bone fragments, as well as the number of fastening screws. In this study, biomechanical modeling of the most commonly used variants of osteotomy of the first metatarsal bone of the foot in the surgical treatment of its valgus deformity was carried out. For this purpose, 10 models of osteotomies of a separate first metatarsal bone were created, which were then subjected to static loading to analyze their stress-strain state and assess their success. Successful (stable and reliable) treatment options were identified, as well as unsuccessful ones. Two of the ten options considered were unsuccessful – scarf type osteotomies with displacement of bone fragments by 2/3 of its diameter and fixed with a single screw. It was revealed that osteotomies of the chevron type showed higher stability in comparison with scarf osteotomies. As a result, we note that in this study, numerical experiments were conducted for the first time to compare the stability and strength of the most commonly used variants of osteotomies based on a single bone model. A biomechanical model of scarf osteotomy of the first metatarsal bone has been developed and validated on the basis of mechanical experiments.

Russian clinical guidelines for the treatment of diseases and injuries of the musculo-skeletal system contain references to the need for careful preoperative planning. In Russian medical organizations, as a rule, the traditional approach to preoperative planning is used, which implies the use of acetate implant templates along with X-ray films. At the same time, representatives of the leading clinics of trauma and orthopedic profile in Russia are of the opinion that digital preoperative planning is a high-precision method for selecting the size of implants, as well as other parameters required for their installation. It is believed that preoperative digital planning and virtual placement of implant templates should be integrated into the preoperative management of implantation patients as a standard procedure. A survey of experts, traumatologists and orthopedists, showed the need for the introduction of computer systems for preoperative planning, which also provide biomechanical support for the decision made and predict treatment results. In this regard, the concept of support systems for making medical decisions in surgery of the spine-pelvic complex has been developed, which lies at the core of the program platform Aссord, which is the basis for the development of preoperative planning systems in surgery of the spine-pelvic complex and large joints. This paper presents the results of the development of the concept, as well as its approbation. The concept developed and presented in this article also opens up opportunities for creating systems to support medical decision-making in other areas of surgery on its basis.

The influence of hydrogen saturation of steel specimens on the results of their standardized testing for resistance to hydrogen cracking has been carried out. The simulation took into account the hydrogen skin effect observed when metal samples being charged with hydrogen in various electrolyte solutions. The classical decohesion model of hydrogen embrittlement HEDE was used. It was shown that, despite the microscopic skin depth, the effect led to a dual fracture pattern, when the specimen’s cross-sectional view exhibited both a hydrogen brittleness area and a normal destruction one. The comparison of calculated results with experimental ones showed the strong influence of the hydrogen skin layer on the results of standardized metal testing. This skin effect plays a significant role in the destruction propagation over a metal sample and should be taken into account when conducting industrial tests, simulations and experimental studies.

The quality of solving the problem of biomechanical modeling largely depends on the created solid-state model of the biological object under study. Building a model based on computed tomography data for a particular patient is possible both in manual mode (software packages for processing medical images) and using automated tools for building a model (image segmentation), which significantly speeds up the process of creating a solid model, in contrast to the manual mode. The complexity of the automated approach lies in the reconstruction of a segmented image into a solid model suitable for biomechanical modeling. As a rule, automatic segmentation is hampered by the presence of anatomical pathologies, noise, and the presence of implants in the images of a digital study. The article proposes a method for creating a solid model from a point cloud obtained from computed tomography data using convolutional neural networks SpatialConfiguration-Net and U-Net. The results of the implementation were applied in the development of the "Module of Solid Models'', which is included in the prototype of the medical decision support system SmartPlan Ortho 3D, which is being developed at Saratov State University within the framework of the project of the Foundation for Advanced Research. The system is included in the register of Russian software.

Patient-specific biomechanical modeling requires not only the geometric model of the studied object of a particular patient, but also the mechanical properties of its tissues. Quantitative computed tomography provides the initial data for geometric modeling, as well as data on X-ray density (Hounsfield units) of the object. It is known that Hounsfield units correlate with mineral density of the scanned objects, as well as with their strength properties. The aim of this study was to determine the relationship between Hounsfield units and Young's modulus values of human femoral heads spongy tissue. This study was conducted on samples of femur bones spongy tissue. The tissue was obtained from patients who underwent total hip replacement for coxarthrosis. Samples were scanned on a Toshiba Aquilion 64 computed tomograph and then subjected to uniaxial compression on an Instron 5944 universal testing machine. As a result of the study, the average Hounsfield units were obtained for each sample, as well as the Young's modules values. Regression dependencies were calculated linking the Hounsfield units and the Young's modulus values of samples of femoral heads spongy tissue in different types of diseases. The obtained dependences allow one to determine Young's modulus value of femoral heads spongy bone noninvasively for a particular patient, depending on his disease, and using it in the process of preoperative planning. Also, the obtained dependencies can be used in biomechanical modeling of diseases and injuries of vertebral-pelvic complex of a particular patient treatment and can be implemented in medical decision support system in surgery of vertebral-pelvic complex.

The purpose of the work was to substantiate the possibility of using rolled foamed polyethylene with a sheet thickness of 50 mm or more as thermal insulation for low-rise frame buildings. This goal was achieved by conducting experimental studies to determine the physical, mechanical and operational properties of foamed polyethylene, assessing the material's resistance to climatic influences and a full-scale assessment of the thermophysical characteristics of the material and the state of structures at the facility. The most significant results are: the results of determining the operating temperature range taking into account mechanical loading and tendency to creep; the results of assessing the effect of the reflective layer; the results of determining the tensile strength of the material on the surface and on the welded joint; field test results. It has been established that products based on foamed polyethylene are resistant to both climatic influences and mechanical loading, the material in the temperature range from minus 60 ° C to + 60 ° C has high operational resistance. The effect of the reflective layer applied to the foamed polyethylene on the mechanical characteristics of the material is insignificant, but it contributes to an increase in the thermal resistance of the insulating shell. Strength characteristics ensure the integrity of the seamless insulation envelope. The significance of the results obtained lies in the substantiation of the technical feasibility and economic feasibility of developing system solutions for the integrated insulation of frame buildings with rolled polyethylene foam.

Quantitative computed tomography along with densitometry is used to assess mineral density and strength of bone tissue. Raw data obtained by computed tomography are converted by software using convolution kernels. It is known that the use of convolution kernels can significantly change tissue density, which is measured in Hounsfield units. The beam-ardening effect is described in literature: when x-ray passes through an object, the absorption of lower-energy x-ray photons occurs. Therefore, scanning objects �in the air� without surrounding soft tissues of the human body gives distorted Hounsfield units relative to their real values. This work is aimed at assessing the effect of various convolution kernels, beam-hardening effect, as well as other CT scanner settings for Hounsfield units. In this work, we studied samples of trabecular bone tissue of the femoral heads and calibrated samples of an aqueous solution of dipotassium hydrogen phosphate with known mineral density. Trabecular bone tissue samples of the femoral heads and calibrated samples of an aqueous solution of dipotassium hydrogen phosphate with known mineral density were scanned on Toshiba Aquilion 64 scanner. The samples were scanned in various modes: at different tube currents, �in the air� and inside the calibration phantom. The resulting images processed by the FC17 and FC03 convolution kernels were analyzed. It was shown that tube current magnitude practically does not affect the Hounsfield units. Different convolution kernels demonstrate significantly different Hounsfield units when scanning the same samples �in the air�. It has been confirmed that the beam-hardening effect significantly affects the Hounsfield units and should be considered when evaluating bone mineral density. No differences were found in measurements �in the air� and in the phantom at a significance level of 5 percent for the FC03 kernel, which confirms the fact that FC03 is intended to correct the beam- ardening effect. An ambiguous relationship was noted between the Hounsfield units and the mineral density for low-density samples when scanned with the FC03 kernel. FC17 kernel, in comparison with FC03, is considered more preferable and suitable for assessing bone mineral density. However, pre-calibration with phantom is required for a wide range of preset mineral densities. Regression dependencies were obtained for recalculation of Hounsfield units from experiments �in the air� to Hounsfield units of the same samples scanned in surrounding tissues (in the phantom).

Aim: development of information exchange methodology between the main participants of health branch in providing of medical care for traumatology and orthopedic patients at the base of specialized registers design. Material and Methods. Analysis and systematization of 31 registers of medical information in the field of traumatology and orthopedics functionality placed in Federal Institute of Industrial Property, European Patent databases, developers' web-sites were made. Search depth was designated from 1979 and was defined by the date of the earlier found information source. Results. Analysis of specialized registries has shown that most of it (70.9%) are mono-nosological and contain information about diagnostic and treatment measures provided at the level of a medical institution. It was developed a methodology of specialized registry of medical information functionality including the information of applied medical devices, pharmaceutical preparations, medical technologies, rehabilitation programs, medical care evaluation results methodology which let operate with the data forming in information systems of the main health branch participants. Conclusion. Proposed information exchange methodology determines the necessity of integrated target-oriented registry development. Its practical use let increase management decisions quality influencing the achievement of health branch participants objectives.

The article presents key provisions of the integral-institutional paradigm, which is a new tool for analyzing institutional development. In the new paradigm, the market and razdatok (nonmarket economies) are viewed as universal development mechanisms. As a result of institutional evolution, during which the razdatok and the market improved their forms, a new reality is being formed in the 21st century, which is no longer in opposition to market and razdatok economies, but in their integration. Integration of the market and razdatok leads to the formation of either a quasi-market model or a contractual razdatok. The key properties of these basic institutional models of the 21st century are analyzed. The quasi-market is the reason for the rent-oriented motivation and stagnation of the economy, while the contractual razdatok is a new universal model leading to dynamic growth. The main result of the paradigm is the justification of the possibility of Russia's transition to the open access social order.

Aim of this study was to investigate the clinical efficacy of the device tuning fork in the treatment of patients with metabolic syndrome. The study included 22 women with metabolic syndrome (age 52-75 years). The average body weight of patients - 92.3 ± 15.2 kg, body mass index - 37.2 ± 2.7, the duration of obesity - 21 years. The results obtained confirm the effectiveness of information-wave therapy in the presence of the metabolic syndrome. It is shown that combined treatment of the metabolic syndrome without the use of information-wave therapy is not accompanied by improvement in basic biochemical parameters. The study observed no deterioration in carbohydrate metabolism, electrolyte abnormalities in patients in both groups.

Some characteristic peculiarities of the 5'-end and 3'-end structures of pre-mRNA isolated from nuclear RNP particles have been investigated: presence of triphosphorylated nucleotides on the 5'-ends, as a characteristic of the primary product of transcription; presence of modified 5'-ends -- blocked and methylated structures -- caps; presence of poly(A) blocks attached to the 3'-end of pre-mRNA during post-transcriptional transformation of the latter. It was shown that pre-mRNA isolated from nuclear RNP particles contained triphosphorylated nucleotides as well as a "cap" structure at the 5'-ends. On the 3'-ends of pre-mRNA from nuclear RNP particles isolated in the presence of a RNAse inhibitor, the presence of poly(A) blocks have been shown. These poly(A) structures are separated very easily from pre-mRNA during mild RNAase digestion. This is the reason why they are not detected in 30S monoparticles, containing pre-mRNA fragments connected with one informofer. Almost all poly(A) complexes in this condition are combined with proteins and have the sedimentation coefficient of about 14S. It was concluded that formation of nuclear pre-mRNA containing RNP-particles take place just after the onset of RNA synthesis. All processing steps occur with pre-mRNA packed in nuclear RNP particles.