Objective. To investigate the effect of local injection of platelet rich plasma (PRP) on periosteal bone formation in a rat model of femoral atrophic non-union. Methods. The study was conducted on 11 rats. Atrophic non-union was modelled by performing a mid-shaft femoral osteotomy with intramedullary Kirschner wire fixation, followed by periosteal stripping (2 mm) at both ends of the osteotomized bone and their separation with a silicone spacer. On day 7 post-surgery, 5 animals received a local PRP injection into the injury zone. Radiography was performed at weeks 2 and 4. After 8 weeks, euthanasia was performed, and the operated femurs were harvested for histological analysis. Results. In the atrophic non-union model, a loose connective tissue capsule of varying thickness without signs of inflammation was found around the spacer in all rats. Acellular areas were identified within the cortex. The structure of the periosteum and endosteum near the osteotomy site was disrupted. In 5 out of 6 animals, no signs of bone formation were observed near the spacer from either the periosteal or endosteal zones. Following PRP injection, a higher density of capillary-type vessels was observed within the capsule. Areas of cartilage with hypertrophic chondrocytes were identified, indicating endochondral ossification. In 4 rats, formed bone tissue was recorded on the fragments, predominantly on one side, in both periosteal and endosteal zones. The bone tissue was cancellous in the periosteal zone and woven bone in the endosteal zone. Conclusion. Local PRP injection into the injury zone on day 7 in a rat model of femoral atrophic non-union with previously disrupted periosteum positively affects periosteal bone formation at the fragment ends.

The bone healing impairment, such as non-union fractures after injuries of long bones, lead to loss of working capacity and result in significant financial costs, which emphasizes the socioeconomic significance of the problem. However, it is not known which method of modeling the non-union bone fractures is more optimal for further research into the effectiveness of biological therapy aimed at treating bone healing impairment. For a detailed study of methods of non-union fracture treatment of, it is necessary to determine the developed animal models. The objective was to analyze the existing animal models of fracture nonunion in long bones in vivo and to consider the possibility of their further use to evaluate the effectiveness of the use of modern biotechnologies for the in the management of fracture nonunion. It was found that the majority of developed animal models of atrophic long bone non-union were created using small animals, namely rats, mice, and rabbits. A more common method of modeling bone non-union is performing an osteotomy with the formation of a defect of different widths between the bone fragments and subsequent removal of the periosteum proximal and distal to the osteotomy site; damage to the endosteum or removal of bone marrow. Also, in such animal models, researchers use a silicone spacer, a polysulfone plate, or a latex-silicone foil to physically prevent fracture union. In these animal models, studies using mesenchymal stromal cells, platelet-rich plasma or bone morphogenetic protein-2 (BMP-2) have already been conducted for the management of non-union bone fractures. At the same time, the clinical results of the application of various biological therapies are ambiguous, which determines the conduct of further experimental studies, in particular, in vivo. However, there are disagreements about which in vivo modeling methods give a reproducible result and prevent bone union, which determines the need for further analysis of existing modeling tools for conducting research in this direction.

A promising method of regenerative medicine is the saturation of allografts with platelet-rich plasma (PRP). Objective. To evaluate the course of metabolic processes after filling a hole defect in the distal metaphysis of the femur with allogeneic bone implants in conditions of additional local administration of allogeneic PRP. Methods. In the model of a hole defect in white rats with the filling of the defect with an allograft, as well as with additional local stimulation of PRP on the 7th day; on the 3rd and 7th days and on the 1st, 3rd and 7th days in blood serum, the content of glycoproteins (GP), chondroitin sulfates (CST), total protein (TP), calcium (Ca), activity alkaline phosphatase (AlP) and acid phosphatase (AcP). The results. 14 day. In the 3-month rats, under one stimulation, an increase in TP and Ca, a decrease in AcP was observed, with two stimulations there was a 1.11 times smaller GP, 1.13 times larger TP and 1.43 times Ca compared to those in rats without stimulation. During three stimulations, the GP was 1.24 times lower than that in animals without stimulation. In the 12-month rats in comparison with the data of rats without stimulation, 1.15 times higher GP, Ca, AlP activity, and 1.44 times more AcP were noted. 28 days of the 3-month rats for one injection exceeded the data of animals without stimulation by 1.34 times for GP, and were inferior to them by 1.31 times for AcP. In the 12-month rats, compared to these animals without stimulation, with three injections, a 1.19 times greater TP was noted. 90 d. In the 3-month rats for one injection showed 1.24 times less CST with 1.28 times lower AlP compared to data from rats without stimulation. 12-month rats exceeded the data of the group without stimulation by 1.43 times for AlP. Conclusions. In rats with an alloimplant (especially at 12 months), an increase in connective tissue formation markers and a decrease in LF activity were observed. Filling the defect with an alloimplant led to an increase in inflammation indicators and an increase in markers of bone tissue formation.

In orthopedic and trauma surgery, bone defects are an increasing clinical problem in daily practice. To fill them, many advantages have bone allografts (BA), namely a large stock of transplantation material. Purpose of the study: to evaluate changes in bone mineral density (BMD) of the femur of rats after filling a distal metaphyseal defect with an bone allograft in combination with the simultaneous administration of mesenchymal stromal cells (MSCs) or platelet-rich plasma (PRP) depending on age. Methods. The model of the hole defect in the metaphysis of the femur in rats (aged 3 and 12 months) investigated BMD in terms of filling BA, including, with the simultaneous administration of MSCs or PRP during surgery. Results. In rats with an unfilled defect — the immutability of BMD during the experiment. Compared with 3-month-old rats in 12-months-old rats with BA BMD was 1.11 times higher on the 14th day (p < 0.05), and on the 90th day it was 1.11 times lower (p < 0.05), on the 28th day it was not differed. In the 3-month-old rats with A and MSC showed a 1.20-fold lower BMD (p < 0.05) on the 28th day, and on the 90th day BMD did not differ compared to the group with BA. BMD in 12-monthold rats with BA and MSC did not differ from the group with BA. In in 12-month-old rats with BA and PRP BMD was 1.18 times (p < 0.05) higher on the 28th day and on the 90th day — 1.14 times (p < 0.05) compared to the BA group, and in 3-month-old rats did not differ for all terms. Conclusions. In the case of filling a bone defect with a bone alograft in 12-month-old rats, the increase of BMD of the femur is slower than in 3-month-old rats. The use of BA with MSCs in younger rats causes a delay in bone regeneration on the 28th day, but does not disrupt this process, according to BMD on 90th day compared to rats with BA, and in older rats does not significantly change BMD during the study. Filling defect BA with PRP promotes the growth of femoral BMD in older rats from the 28th d ay, b ut i n y ounger r ats it d oes n ot c ause significant changes compared to the group with BA.

Mesenchymal stem cells (MSC) can be used to facilitate reparative osteogenesis. In the case of critical-size defects, MSC can attach to allogenic bone implants (AlloI) that serve as a matrix. Objective. Analyze the morphological features of reparative osteogenesis in critical-size defects in femurs of rats (3 and 12 months old) when the defects are filled with MSC along with AlloI. Methods. 60 white lab rats, 3 months (n=30) and 12 months (n=30) old were used. Defects (3mm in depth, 3mm in diameter) were created in the femoral metaphysis of each rat, and filled with AlloI in the control groups and with AlloI and adipose-derived MSC in the experimental groups. Each group contained 15 rats of a particular age. 14, 28, and 90 days after the surgery, histological studies were conducted. Results. The area of AlloI decreased with time. 14 days after the surgery, in the experimental group, the area of AlloI was 1.6 times greater in 3-month-old (3mo) rats than in 12-month-old (12mo) rats. In comparison to the control, the area of AlloI was greater 14 days after surgery in 3mo rats and 28 days after surgery in 12mo rats. 14 and 28 days after the operation, the area of connective tissue was greater in rats of both experimental groups than in the control. For the 3mo rats, the same was true 90 days after the operation. The area of newly formed bone was 1.6 times lower in 3mo rats than in 12mo rats 14 days after the operation. 90 days after the operation, the area was 2.3 greater in 3mo rats. For 12mo rats, the highest area of bone tissue occurred 14 days after the surgery, and subsequently did not significantly change or differ from the control. For 3mo rats, the area of bone tissue was lower than control 14 and 28 days after the surgery, but greater than control 90 days after the surgery. Conclusions. The use of MSC along with AlloI to fill traumatic bone defects causes slower bone formation and excessive formation of connective tissue, independent of the age of the recipient.

Bone defects that do not heal on their own are a significant problem in orthopaedic and trauma surgery. One of the approaches to its solution is the use of bone alloimplants (AloI). Objective. On the basis of the analysis of biochemical indicators of the metabolism of connective tissue in the blood serum of laboratory rats, the course of metabolic processes after the filling of the defect in the metaphysis of the AloI femur was evaluated. Methods. A model of creating a transcortical defect of critical size (diameter 3 mm, depth 3 mm) in the metaphysis of the femur of 3- and 6-month-old rats was used. In animals of groups I (n = 15, age 3 months) and III (n = 15,12 months) the defects were left unfilled, II (n = 15, 3 months) and IV (n = 15, 12 months) — filled with structural AloI. After 14, 28 and 90 days, the content of glycoproteins, total chondroitin sulphates (CS), protein and calcium, activity of alkaline and acid phosphatases in blood serum was investigated. Results. The introduction of AloI leads to an increase in the content of glycoproteins for all periodsof observation in rats of both age groups. 14 days after implantation in 12-month-old rats, compared to 3-month-old rats, a 1.30 times higher level of CS in blood serum was determined (p = 0.008), which is due to their higher content in the area of connective tissue implantation; the activity of alkaline phosphatase decreased by 1.80 times p = 0.016) and acid phosphatase by 1.50 times (p = 0.018), which indicates a delay in the formation and reorganization of bone tissue. However, the level of CS under the conditions of the establishment of AloI on the 90th day was lower compared to the correspondinggroups without plasticity of the defect: in 3-month-old rats by 1.44 times ( p = 0.008), in 12-month-old rats by 1.52 times (p = 0.008). Conclusions. According to the indicators of biochemical markers of connective tissue metabolism, the use of AloI for plasticity of defects of a critical size in the metaphysis of the femur of rats leads to the activation of bone regeneration with a greater manifestation in younger recipients compared to groups with an unfilleddefect.

Mesenchymal stem cells (MSCs) are used for the improvement of the repair of allografts. Aim. Based on the analysis of cytokines and proteins of the extracellular matrix in the blood serum of laboratory rats, to evaluate the course of metabolic processes after filling a defect in the femoral metaphysis with allogeneic bone implants saturated with MSCs. Material and Methods. On the model of a transcortical defect in the metaphysis of the femur, the content in the blood serum of 3 and 12 months white rats of interleukin-1 (IL-1), interleukin-6 (IL-6), transforming growth factor-b (TGF-b), osteocalcin (OC) and osteopontin (OP) on the 14th, 28th and 90 days was investigated. Results and Discussion. Use of MSCs in 3-month-old rats led to an increase in IL-1 concentration: 0.300(0.269; 0.329, 0.308(0.273; 0.339), 0.295(0.271; 0.319) pg/ml of IL-1 for the 14th, 28th and 90th days, respectively, which higher than the level of rats without MSCs by 1.69 (p=0.008), 1.37 (p=0.008) and 1.46 (p=0.008) times, respectively. For 12-month-old rats: IL-1 (0.414(0.387;0.437), 0.426(0.389; 0.448) and 0.407(0.368;0.423) pg/ml on the 14th, 28th and 90th days, respectively), which exceeded the data of rats without MSCs in 1.69 (p=0.008); 1.38 (p=0.008) and 1.46 times (p=0.008). In the blood serum of rats with MSCs TGF-b: 3-month: - 1.826(1.637;2.015), 1.379(1.247; 1.568) and 1.675(1.476;1.893) ng/ml on the 14th, 28th and 90th days, respectively, which was 1.57 (p=0.008), 1.98 (p=0.008) and 1.51 (p=0.008) times less than the data of the comparison group; 12-month-old - 1.976(1.749; 2.234), 1.492(1.218;1.734) and 1.813(1.636;2.028) ng/ml on the 14th, 28th and 90th days, respectively, which is less than the level of rats without MSCs of 1.50 ( p=0.008), 1.92 (p=0.008) and 1.51 (p=0.008) times. When introducing MSCs OP: 3-month-old rats - 13.55(12.90; 14.04), 14.14(13.43;14.87) and 14.12(13.75;14.77) ng/ml, which was higher than in rats without MSCs in 1.11 (p=0.008), 1.11 (p=0.008) and 1.17 (p=0.008) times; 12-month-old - 15.26(14.70; 15.81), 16.38(15.88; 16.91) and 16.06(15.53; 16.67) ng/ml, which is more than the comparison group 1.11 (p=0.008), 1.16 (p=0.008) and 1.22 (p=0.008) times; Conclusions. Saturation of allografts with MSCs led to an increase in biochemical markers of inflammation from the 14th day. Bone remodeling in rats with MSCs was characterized by lower activity. In 12-month-old rats in comparison with 3-month-old animals we noted more active inflammation, with a slowed activity in bone remodeling.

The increase in injuries and gunshot wounds because of the war in Ukraine makes it imperative to find methods for optimizing bone regeneration and filling large-size bone defects. Aim. Study morphological features of reparative osteogenesis when critical size femoral bone defects in rats in the early reproductive and mature stages are filled with allografts saturated with blood plasma growth factors (GF). Methods. Defects (3 × 3 mm) were created in the distal femoral metaphysis of 60 white laboratory rats, 3-months-old (n = 30) and 12-months-old (n = 30). The defects were filled with bone allografts saturated with GF in the two experimental groups (AlloG+GF), and unsaturated bone allografts in the two control groups (AlloG). All groups contained 15 rats of each age. At 14, 28 and 90 days after the surgery, 5 rats from each group were sacrificed, and histological analyses were performed. Results. In the AlloGgroups, excessive formation of connective tissue was observed 14 and 28 days after the surgery, most evident in the 3-monthold rats. In the AlloG+GF groups, bone formation was delayed at 14 days independent of age, while at 28 and 90 days, the area of bone trabeculae did not differ from the values in the AlloG groups. Throughout the experiment, decreases in allograft area (almost all of it was replaced by bone after 90 days) and connective tissue (completely absent in 3-month-old rats after 90 days) were observed in both AlloG+GF groups. The area of bone trabeculae increased in the period from 14 to 28 days. Conclusion. Saturating allografts with blood plasma growth factors facilitates an increase in the rate at which allografts are replaced by bone tissue, independent of the recipient’s age. However, excessive formation of connective tissues in the defect 14 and 28 days after the surgery, especiallyin 3-month-old rats, may negatively affect the mechanical properties of the bone, which should be considered in clinical practice.

The purpose of the study was to analyze estimated biochemical parameters of mineralization in the blood serum of laboratory rats, to evaluate the course of metabolic processes in bone tissue after filling the defect in the metaphysis of the femur with allogeneic bone implants. Materials and methods. The work uses a model of creating a transcortical defect in the femur metaphysis of a critical size in white rats. Indicators of mineralization of bone tissue in the blood serum of white rats were studied: the content of total protein, calcium, alkaline and acid phosphatase activity, the ratio of alkaline to acid phosphatase activity, as well as the degree of mineralization, were calculated. Based on the results of a biochemical study of the blood serum of 3- and 12-month-old experimental rats with a critical size defect in the metaphysis of the femur with filling of the defect with bone alloimplants and without filling, it was determined that the introduction of alloimplants into the defect zone of the femoral metaphysis led to an acceleration of the course of mineralization of bone tissue in experimental rats of both age groups. Results and discussion. The introduction of alloimplants into the defect zone of the femoral metaphysis led to an acceleration of bone tissue mineralization in experimental rats of both age groups. Thus, on the 28th day when alloimplants were introduced, the ratio of alkaline and acid phosphatase activity in 3-month-old rats was by 1.26 times higher than the corresponding indicator in experimental animals without defect filling (p=0.008), as well as by 1.34 times – the level indicator on the 14th day. Both in the conditions of using alloimplants to fill the defect, and in the case of an unfilled defect for both age groups, the maximum manifestation of markers of bone tissue formation was recorded on the 28th day of the experiment, and the values of this maximum were higher in the group of animals with alloimplants. If in the case of an unfilled defect on the 90th day there was a sharp decrease in the analyzed indicators, which indicates the actual cessation of the mineralization process, then under the conditions of using alloimplants the decrease was less pronounced, which is a sign of the continuation of these processes. In 3-month-old animals with an unfilled defect, the stages of mineralization processes passed faster and these processes were more developed at the same time. The ratio between the activity of alkaline phosphatase and acid phosphatase in blood serum has proven to be a more informative and sensitive indicator than the degree of mineralization. Conclusion. Treatment of experimental rats with a critical size defect in the metaphysis of the femur with alloimplants leads to the detection of biochemical signs of activation of regenerative processes in them, but this activation quickly decreases in intensity, is insufficient and requires additional strengthening due to certain external influences

Insufficient bone regeneration is a common issue for patients with extensive bone damage, therefore the use of allografts is required.With increasing life expectancy, there is a higher risk of bone repair issues after fractures or orthopedic surgical intervention.We studied incorporation and remodeling of structural allografts in critical size metaphyseal femur defects in 52 rats aged 3-month-old and 12-month-old who underwent surgeries creating a bone defect, which was either filled with a structural allograft (3-month-old -3moAllo; 12-month-old -12moAllo) or left empty (3-month-old -3moE; 12-month-old -12moE).Histological analyses were performed 14, 28 and 90 days after the surgery.The percentage of bone and fibrous tissues, and allograft relative to the defect area was evaluated.The transmission electron microscopy was carried out 14 days after allograft implantation.When the defect was empty, slower bone regeneration was observed in 12moE rats versus 3moE, leading to sufficient irregularities in the anatomic structure of the femur 90 days after the surgery.When a structural allograft was used, the area of the fibrous tissue was larger in the defects of 12moAllo compared with 3moAllo rats 90 days after surgery.No age-related differences were found in the allograft remodeling and structures of the osteocytes, osteoblasts, and osteoclasts over the observation period.Evident issues with bone regeneration were found in critical size defects both of 12moE and 12moAllo rats.However, the allograft use allowed the bone maintaining anatomic structure 90 days after the surgery.

In this research, thin nanostructured Zr and ZrO 2 coatings were deposited onto polypropylene mesh implants for hernia repair surgery by using vacuum-arc evaporation in pulsed mode in a Bulat-type facility. The structure, surface morphology, phase composition of the obtained coatings has been investigated by means of optical and scanning electron microscopy, energy-dispersive spectroscopy (SEM + EDS), X-ray diffraction analysis (XRD), X-ray fluorescent analysis (XRF). The experimental and clinical study on rats considering tissue response to the subcutaneous implantation of synthetic polymer endoprostheses with bioinert coatings has been carried out. The choice of a set of biochemical tests was due to the need to identify the intensity of the inflammatory process after implantation (glycorotene content) and assess the functional status of the liver (ALT, AST) and kidneys (urea, creatinine) and basic metabolites such as glucose total protein and cholesterol. The use of these indicators assessed the toxic effects of the implanted coated meshes.

Bone loss and significant acetabular defects remain one of the major problems in revision hip arthroplasty. A promising material for grafting of bone defects can be materials based on allogeneic bone after various types of processing, combining optimal properties for osteoregeneration. Objective. To analyze the results of acetabular reconstruction with bone implants «OMS-A» in the case of revision arthroplasty. Methods. The results of examination and treatment of 57 patients (33 women and 24 men) were analyzed. The patients’ age at the time of hospitalization ranged from 24 to 81 years. Patients were diagnosed on the basis of a combination of clinical ma­nifestations of the disease, laboratory data, radiography, computed tomography with 3D reconstruction. According to the classification of W. G. Paprosky, the largest group consisted of type I defects — 25 patients (44 %), II — 13 (23 %), III — 19 (33 %). For the reconstruction of the acetabulum, 21 patients (37%) we used fragmented cortical-cancellous pieces (CGP), 28 (49 %) — volumetric bone implants (OCI), 8 (14 %) — a combination of CGP and OCI. All patients underwent revision hip arthroplasty with an anterolateral approach according to Harding. The resulting acetabular defect was tightly filled with an allografts. Results. X-ray and G. A. Gie results were assessed as good in 36 patients (63 %), satisfactory — in 14 (25 %). The manifestations of infection associated with the use of bone implants «OMS-A» have not been determined. The necessity for repeated surgery in order to restore the acetabulum occurred in 7 patients (12 %). Conclusions. Тhe clinical efficiency of bone implants «OMS-A» for the reconstruction of the acetabulum according to the classification of W. G. Paprosky was: with type I defect — 92 %; with type I and type defect — 92.3 %; with type II and type defect — 78.9 %.

The number of elderly people is constantly increasing all over the world. They are most often the patients who need orthopedic surgeries like arthroplasty, osteosynthesis and others. It is knownthat the process of bone regeneration depends on the patient’s age. However, certain characteristics of bone regeneration process depend on the age remain unclear, which is important for developingthe best strategies for treatment of elderly patients. Objective. Тo identify age-related features of bone regeneration and to establish possible ways of influencing them in order to optimize the boneregeneration in elderly patients. Methods. Literature search was performed in the PubMed database. Inclusion criteria were original experimental and clinical studies in English. The search depth is accepted for 20 years. Results. It has been experimentally and clinically shown that bone tissue regeneration slows down with age, which is more pronounced in women. According to scientific information, this involves two signaling pathways — Notch and Wnt/β-Catenin, the activity of which is suppressed with age. However, the regulation of regeneration is a cascade of signaling pathwaysand macromolecules. The expression of growth factors after fracture changes at older age compared to a younger one. In particular,a decrease in the expression of TGFβ-1 was clinically revealed. In addition, in older patients after fracture, an increase in macrophage colony-stimulating factor and VEGF was recorded. It has been experimentally established that a combination of a slowdownin bone tissue regeneration with a decrease in the content of Indian Hedgehog, Sonic Hedgehog, BMP-2, 4, -7 proteins and MMP-9 in bone callus has been established. Among the ways to overcome the delayed bone regeneration in elderly patients can be the use of modern technologies of cell and gene therapy, inhibitors of macrophages, biologically active factors at certain stages of bone regeneration. For cell therapy, it is important to take into account the age of the cell donor because of the high probability of functional disorders in cells from older donors.

The paper describes a practical method for real-time measurement of active power in a dielectric barrier discharge by calculating a Lissajous figures based on the Manley formula. Such a method is very useful for controlling the output ozone concentration in ozone generators taking into account the active power in a DBD reactor. A dielectric barrier discharge (DBD) in atmospheric pressure air was excited by a high-voltage pulse power supply. The active power of the reactor was estimated from the area of the Lissajous figure formed by the V-Q traces, which is directly proportional to the energy consumed per cycle at voltages of 8 and 12 kV, respectively.

Bone loss and significant acetabular defects remain one of the major problems in revision hip arthroplasty. A promising material for grafting of bone defects can be materials based on allogeneic bone after various types of processing, combining optimal properties for osteoregeneration. Objective. To analyze the results of acetabular reconstruction with bone implants «OMS-A» in the case of revision arthroplasty. Methods. The results of examination and treatment of 57 patients (33 women and 24 men) were analyzed. The patients’ age at the time of hospitalization ranged from 24 to 81 years. Patients were diagnosed on the basis of a combination of clinical ma­nifestations of the disease, laboratory data, radiography, computed tomography with 3D reconstruction. According to the classification of W. G. Paprosky, the largest group consisted of type I defects — 25 patients (44 %), II — 13 (23 %), III — 19 (33 %). For the reconstruction of the acetabulum, 21 patients (37%) we used fragmented cortical-cancellous pieces (CGP), 28 (49 %) — volumetric bone implants (OCI), 8 (14 %) — a combination of CGP and OCI. All patients underwent revision hip arthroplasty with an anterolateral approach according to Harding. The resulting acetabular defect was tightly filled with an allografts. Results. X-ray and G. A. Gie results were assessed as good in 36 patients (63 %), satisfactory — in 14 (25 %). The manifestations of infection associated with the use of bone implants «OMS-A» have not been determined. The necessity for repeated surgery in order to restore the acetabulum occurred in 7 patients (12 %). Conclusions. Тhe clinical efficiency of bone implants «OMS-A» for the reconstruction of the acetabulum according to the classification of W. G. Paprosky was: with type I defect — 92 %; with type I and type defect — 92.3 %; with type II and type defect — 78.9 %.

Finding the optimal graft for filling bone defects and optimizing reparative osteogenesis are actual problems of orthopаedics and traumatology. The peculiarities of the restructuring and the biocompatibility of plastic materials saturated with bioactive factors of blood serum are poorly understood.Objective: to study the morphological features of reparative osteogenesis when using allo- and xenografts in combination with the bioactive factors of blood serum for the filling of rabbit humerus defects.Methods: аn experimental study was conducted on the 20 rabbits of the Californian breed (6 months old), which were implanted of cancellous allograft or xenograft in combination with bioactive factors of blood serum in the defect of the proximal metadiaphysis of the humerus. Allo- and xenografts with a diameter of 7 mm, a length of 10 mm were made from the humerus of donor rabbits and pigs and immersed in autologous serum with bioactive factors for 20 minutes immediately before the surgery. Histological analysis was performed after surgery on the 21th and 90th days.Results: іn the case of the use of allografts on the 21th day of observation, the process of their restructuring, the formation of the new bone and the beginning of its remodeling were recorded. On the 90th days after implantation, a complete restructuring of the allografts and the filling of the defect with a lamellar bone were established. When using xenografts, their replacement was established with predominantly fibrous tissue, which for 21th days occupied more than a third of the defect area, and for the 90th, more than half. The relative area of the new bone tissue was 1.8 and 8.2 times less compared with the use of the allograft (p < 0.01), respectively.Conclusions: аllografts rearrangement is faster compared to xenografts, and for 90th days the defect is filled with lamellar bone tissue. Slowed rearrangement of the xenograft is associated with the formation of fibrous tissue around it.

Научная новизна статьиВпервые проанализированы методы выявления слабых А и

Methods: The results of examination and treatment of 11 patients (8 boys, 3 girls, age from 5 to 16 years) were analyzed. The diagnosis was made on the basis of a combination of clinical manifestations of the disease, laboratory test data, X-ray and pathomorphological studies. Distribution by localization of the pathological focus: proximal femur 6 (54.5%), humeral 2 (18.2%), calcaneal 2 (18.2%), pubic 1 (9.1%). Indications for surgical treatment: the presence of a massive focus of bone tissue destruction in the loaded area, a high risk of a pathological fracture, pronounced long-term pain syndrome. All patients underwent marginal resection and chemical treatment of SBC, the defects were filled with osteoplastic material.

Objective: on the base of literature we analyzed different methods of mesenhymal stem cells using for optimization of bone regeneration.Methods: we reviewed publications for the last 90 years from electronic data base PubMed, MEDLINE, thesis, articles, manuscripts and other relevant science sources of medical information. We have found more than 200 scientific works, 86 were included for analysis.Results: mesenhymal stem cells have unique abilities — to differentiate into soft tissue cells and multiply in vitro, they possess immune modular and immune suppressive effects. It gives possibility to use them for therapeutic method in regenerative medicine for bone osteogenesis. In review we presented sources of mesenhymal stem cells, ways to get bone marrow puncture and its transplantation, mesenhymal stem cells culturing and possibilities to differentiate them into certain direction. We gave examples of independent and complex (with different implantation materials) using of mesenhymal stem cells. It was shown that mesenhimal stem cells transplantation had positive influence on bone regeneration process, it enlarge osteoblast differentiation, volume of new formed bone tissue and decrease the terms of bone formation. Advantages of mesenhymal stem cells using are minimal invasive procedures and possibility to enlarge number of cells during culturing. But during culturing cells become older and the growth slows down. Creation of bioconstructions on the base of different matrix can facilitate introduction into defect area and create a graft with required shape and size. Choice of material for matrix is debated issue. So further studies of complex bioengineering constructions which will possess peculiarities of bone tissues are go on.

The issues of bone regeneration remain relevant even with the active development of biotechnology. The use of platelet-rich plasma to optimize osteoporosis is one of the promising directions in modern medicine.Objective: to performa comparative analysis, to generalize and systematize the results of studies on the classification, methods of obtaining and the possibility of using plasma-enriched platelets in animal experiments, and also in clinical conditions.Methods: publications over the past 20 years have been analyzed from the electronic databases of PubMed, Medline, abstracts, articles, abstracts, dissertations and other relational sources of scientific and medical information. Over 200 works have been found.Results: based on the information collected, the following issues were highlighted: receiving and classifying platelet-rich plasma, studying the effect of platelet-rich plasma on cells in vitro, and the possibility of combining platelet-rich plasma with biomaterials in animal experiments. In addition, the possibility of using platelet-rich plasma to restore bone tissue in a clinic in vivo is considered. It has been established that the use of platelet-rich plasma is one of the most promising modern methods for optimizing bone regeneration. The safety, efficacy and cost-effectiveness of platelet-rich plasma use are well documented in scientific literature. However, the main disadvantage of platelet-rich plasma is insufficient strength characteristics, which is a very important parameter for using it to fill bone defects, especially of critical size, in the case of osteotomy and surgical treatment of cancer. In this regard, the combination of platelet-rich plasma with osteoplastic materials, mesenchymal cells and growth factors is of particular interest. However, there are many controversial issues that require additional studies to create a transplant with properties that are as close as possible to the biological characteristics of the bone.