Introduction Replacement of bone defects is an important issue of modern traumatology and orthopedics. With increasing technological advances there is a spectrum of bone-substituting materials, and the choice of the effective option is essential for biomedical research. The objective was to determine the effect of the three-dimensional structure and pore size of tricalcium phosphate based bone substitute materials on osteoconduction using a critical diaphyseal defect of the rat femur. Material and methods A monocortical 7 mm defect was simulated in the middle third of the rodent femoral shaft under anaesthesia and filled with blocks of one of four tricalcium phosphate based materials differing in the number, size and direction of pores. Eight rats from each group were sacrificed at 3 and 6 months, and the newly formed bone was histologically examined and the results compared using statistical methods. Results The bone tissue was shown to grow into the defect area through the pores of the material in all the groups at 3 and 6 months, The newly formed bone measured (11 ± 4) % and (31 ± 6) % of the defect area in the Cylinders group, (14 ± 5) % and (29 ± 4) % in the Gyroid group; (39 ± 5) % and (41 ± 7) % in the Gyroid-150 μm group and (17 ± 7) % and (27 ± 8) % in the Gyroid-50 μm group, respectively. The area of newly formed bone was statistically greater in the Gyroid-150 µm group compared to that in the other groups (p < 0.05, Kruskal – Wallis test). Discussion The effect of the type of architecture of the bone substitute material, the pore size and their relationships are reported in many studies with larger diameter pores (more than 600 μm) improving osteoconduction, and the upper limit of porosity being limited by a decrease in the mechanical properties of the block. The advantages of the Gyroid structure over other types of architectures are described in theoretical and applied research. Structures with pores of different sizes were examined in few studies, and our findings demonstrated the feasibility of using the complex structures and the role in replacing bone tissue. Conclusion The three-dimensional structure of bone substitute materials based on tricalcium phosphate was shown to have an effect on osteoconductive properties, with an additional pore mode with a diameter of 150 μm added to the Gyroid structure leading to significantly greater experimental bone tissue ingrowth in the sample.

BACKGROUND: Femoral neck fractures are among the most common injuries of the human skeleton. If in 2004 in Russia the incidence of fractures of the proximal femur in patients over 50 years of age was 105.9 per 100,000 of the population (and in women this figure was almost twice as high as in men), it is expected that by 2025 the number of victims worldwide will have doubled, and by 2050 it will be almost 4.5 million. Existing osteosynthesis techniques do not take into account the peculiarities of the uneven distribution of bone density in the femoral head, which can lead to the placement of fixators in a deliberately weakened area, reduced strength of osteosynthesis, migration of fixators and, as a result, non-union of the fracture. AIM: To compare the long-term results of dynamic derotation osteosynthesis with the results of femoral neck fracture osteosynthesis with cannulated screws, dynamic hip screws, and V-wires. MATERIALS AND METHODS: The study was based on the analysis of the results of surgical treatment of 259 patients with femoral neck fractures. In the treatment of 114 (44%) patients (study group), the titanium dynamic derotational fixator Targon FN manufactured by Aesculap B. Braun (Germany) was used. The comparison group included 145 (56%) patients who underwent osteosynthesis using a dynamic femoral screw (40 patients), tensioned V-wires (60 patients) or 3 AO screws (40 patients). There were no significant differences in the distribution of patients by age in the groups considered, which was confirmed by pairwise tests using Holm's multiple comparison correction method. RESULTS: In Garden III femoral neck fractures, 59.6% of the study group achieved consolidation compared to 34.5% with dynamic hip screw implantation, 22.7% with V-wires and 28.0% with cannulated screws. In Garden IV fractures, consolidation did not occur in any of the observations. The incidence of avascular necrosis of the femoral head is highest in Garden III fractures: 39.2% with dynamic femoral screw implantation, 30.1% with V-wires, 34.2% with cannulated screws and 21.8% with dynamic derotational osteosynthesis. When evaluating the long-term results in patients with consolidated fractures, claudication of the operated limb was observed (in Garden III type fractures in 64% of cases — when using a dynamic derotational fixator, 65% — when using a derotational femoral screw, 100% - when using cannulated screws and V-wires). The maximum femoral neck offset shortening of more than 15% was observed in 7 patients (39%) with dynamic derotational osteosynthesis, in 6 patients (67%) with dynamic femoral screw implantation, in 5 patients (60%) with cannulated screws and in 8 patients (80%) with V-wires. CONCLUSION: Garden I fractures of the femoral neck do not lead to avascular necrosis of the femoral head. As the angle of the fracture plane increases and the blood supply to the femoral head decreases, the incidence of avascular necrosis increases. The development of claudication in the patients was caused by the reduction in femoral offset length due to osteolysis, which occurred as a result of both the localisation of the fracture plane (fracture factor) and the dynamic function of the implant (fixator factor). Lameness was therefore considered to be the 'payback' for the consolidation of the fracture.

Finite dimensional modeling is the most important method of modeling biological objects. Our goal was to apply this method to build thorax models for patients with pectus carinatum. We presented a workflow for building finite element models from CT scans with the focus on using free open-source software, including 3D Slicer and Ansys Student. We also developed a mechanical model of a flat rib under load and proposed a method for its parameters' identification. The rib is modeled by five rigid rods connected by torsion springs. We took into account the compliance in costovertebral joint by including to the model two cylindrical springs that connect the head of the rib with fixed perpendicular planes (which models that corresponding vertebra is fixed). There is also a torsion spring in the head of the rib that hinders the rotation of the rib in costovertebral joint. The load is applied to the free end of the last rod in the system. We obtained the equations of equilibrium for the described system. Stiffnesses' identification was made from the assumption that small displacements of the first rod's free end and displacements of non-fixed end of homogeneous isotropic linear elastic curved beam are equal.

Background. Free perforating flaps are the most optimal for reconstruction of both upper and lower extremities. However, along with the obvious advantages of these flaps, there are also a number of difficulties associated with their more complex vascular anatomy and, as a consequence, more time-consuming dissection. This determines the need for a more thorough preoperative planning, including the mapping of perforating vessels and development of flap design. At the same time, the problems with intraoperative assessment of perfusion of perforating flaps and their monitoring in the postoperative period have not been solved. For these purposes, several instrumental methods of examination such as MRI and CT angiography, Doppler sonography, ICG and dynamic infrared thermography are used. Aim of the study — to evaluate the capabilities of dynamic infrared thermography (DIT) for mapping of perforating vessels when planning the design of perforating flaps, as well as for assessing their intra- and postoperative perfusion. Methods. We have analyzed the results of using DIT along with CT-angiography and Doppler sonography for preliminary mapping of perforating vessels in the design of 18 perforating flaps (ALT flap — 10, SCIP flap — 8) transplanted in 15 patients from 01.01.2022 to 30.07.2022. DIT was also used in all cases for intraoperative instrumental confirmation of flap perfusion and for its monitoring in the postoperative period. Results. A total of 39 perforating vessels were detected by CT angiography at the point of origin from the main arteries. DIT was used to detect the distal portions of 37 perforating vessels in 15 patients at the marking of 18 flaps. On average, 2.5 per ALT flap and 1.4 per SCIP flap. Thermographic examination time was approximately 10 minutes. Localization of all perforating vessels detected by DIT were first confirmed by Doppler sonography and then visualized intraoperatively during flap dissection. Intraoperatively, perfusion of all transplanted flaps was clearly confirmed by DIT. In the postoperative period, perfusion problems were clinically detected in 3 (16%) flaps and confirmed by DIT: venous stasis — 2 cases, arterial insufficiency — 1 case. In two patients (13%) with a body mass index of more than 35 (corresponding to class 2–3 obesity), the location of perforating vessels could not be determined by thermography and Doppler sonography. Also, in these patients DIT was ineffective for confirmation of flap perfusion intraoperatively and in the postoperative period. Conclusion. This study confirms that CT angiography, Doppler sonography and infrared thermography are complementary methods that allow to detect and visualize perforating arteries from their origin from a main artery to the site of their passage through the deep fascia (CT-angiography), as well as to determine their more accurate projection on the skin surface (DIT and Doppler sonography). DIT is also an auxiliary method for flap monitoring in the intraoperative and postoperative periods, which allows to engage nursing staff in postoperative monitoring.

Kristaps Juris Keggi was born on August 9, 1934 in Riga in the family of surgeon Janis Keggi. In 1944, the family moved to Germany and then to the United States, where Kristaps received his medical education at Yale University. In 1966, he became an associate professor at the University’s Orthopaedic school and focused on hip and knee arthroplasty. In the 70s of the twentieth century, Kristaps Keggi developed direct anterior approach to the hip joint and started to do arthroplasty using a minimally invasive technique. Over the years, he performed more than 10,000 total hip replacements with his technology at hospitals in New Haven and Waterbury, Connecticut, and authored 135 scientific papers and monographs. In 1989, Kristaps became a Clinical professor of Orthopaedics and Rehabilitation at Yale Medical School and in 2008 was elected a Full professor. During this time, he trained hundreds of residents and became the founder of his own orthopedic school. Keggi was known for a variety of innovative technologies that were widely used all over the world. In 1988, Keggi organized a non-profit Orthopedic Foundation to provide educational programs for official academic exchanges between the United States and the republics of the USSR. For 10 years, more than 300 doctors from Russia, Belarus, Ukraine, the Baltic States, Central Asia, Vietnam and East Germany have received scholarships and the opportunity to learn the basics of the hip and knee arthroplasties In parallel, he traveled to the clinics with lectures, seminars and demonstration surgeries. For outstanding services to national healthcare, in 1993 he was elected a Foreign Member of the Russian Academy of Medical Sciences and, subsequently, the Russian Academy of Sciences. In 2012, Professor Keggi was awarded the silver medal “For Medical Dignity and Service to Russian Medicine”. A brilliant surgeon, inventor, scientist and teacher, successful athlete, philanthropist, Kristaps Juris Keggi died on July 4, 2023, leaving in our hearts a feeling of deep respect and vivid impressions from communicating with him.

BACKGROUND: Owing to its clear clinical manifestation, pectus carinatum is often the reason for the initial visit to the doctor of children with several concomitant orthopedic abnormalities. AIM: To identify concomitant orthopedic disorders in children with pectus carinatum and assess their frequency, clinical manifestations, and relationships with various modifiable and non-modifiable factors. MATERIALS AND METHODS: This observational, single-center, cross-sectional study included 147 patients aged 5–17 years with pectus carinatum. Orthopedic examination and radiography of the spine were performed. Categorical values were described by reporting absolute values and percentages in the sample and quantitatively using arithmetic averages and standard deviations. The Student’s T-test and Chi-square coefficient were used for assessing the relationship (p 0.05). RESULTS: In 3/147 (2.0%) children, pectus carinatum was a symptom of genetically confirmed Marfan syndrome. Among 147 children with pectus carinatum, 56 (38.1%) complained of back pain, 125 (85.0%) had a mobile plano-valgus foot, and 108 (73.5%) had postural disorders. Scheuermann disease was detected in 22 (15.0%) children and signs of spinal osteochondrosis in 57 (38.8%). Back pain was associated with sclerosis/usuration of the vertebral end plates. Children who regularly engaged in sports involving forceful load on the back muscles complained of pain less often, regardless of the degree of spine deformity. CONCLUSIONS: Mobile flat foot, sagittal component of posture disorders, and spinal osteochondrosis are common in children with pectus carinatum. Thus, children with keel chest deformity should undergo orthopedic examination and spinal X-ray in a standing position. Because of the high incidence of back pain and its association with insufficient muscular frame development, children with pectus carinatum are recommended to regularly engage in physical therapy and/or sports associated with loads on the back muscles.

In this study, we propose a new phenomenological approach to human chest modeling. We model the chest as an elastic truss consisting of stiff beams connected by spherical joints that hinder the relative rotation of the beams. We used this model to simulate the rib flaring effect, which is a side effect for bracing treatment of patients with pectus carinatum. We used the Ansys software that allowed us to apply finite element method (FEM) to build the model of a chest of a real patient using geometry from the CT scan. We applied a compressive force to a keel of the model and observed the effect of rib flaring. We also examined the applicability of Ansys Mechanical for modeling trusses with beams and spiral springs. For this purpose, we built two simplified models of a system of two beams under compression and then compared the theoretical solution of its equilibrium problem with the solution obtained in Ansys.

Background. The problem of bone defects replacement is relevant nowadays, that is why many scientists create new synthetic bone substitutes, but the ideal material has not been found so far. The aims of the study: 1) to determine the suitability of the monocortical defect model in the rat femur diaphysis with additional prophylactic reinforcement with a bone plate for assessing the biological properties of implanted materials using the commercially available ChronOS material as an example; 2) to assess of the osteoconductive properties of composite materials based on poly(ethylene glycol)diacrylate and octacalcium phosphate with architecture Kelvin and gyroid types on the developed model. Methods. A prospective study, level of evidence II. A monocortical defect of the rat femoral diaphysis (length 7 mm) was produced under anaesthesia in aseptic conditions and fixed with a polyetheretherketone plate and six titanium screws. In the control group, the defect was left empty. In other groups, blocks of one of three materials were implanted сhronOS and composites of poly(ethylene glycol)diacrylate and octacalcium phosphate with 3D-printed Kelvin and gyroid architectures. After 3 and 6 weeks, the rats were sacrificed, and histological examination of the defect zone was performed. The amount of newly formed bone tissue was histometricly assessed, followed by statistical processing of the results. Results. All rats have reached the planned endpoint, and there were no infectious complications or loss of fixation. Histological examination of the defect zone revealed minimal bone growth in the Control group, rather slow bone formation in the Gyroid group, and statistically significantly more pronounced bone formation in the pores of the materials in the Kelvin and Chronos groups. Conclusions. Bone defect in this model was not spontaneously filled with bone tissue and allowed us to study the biological properties of bone substitutes (the ability to biodegrade and osteoconductive properties). The osteoconductive properties of a composite material based on poly(ethylene glycol)diacrylate and octacalcium phosphate with a Kelvin architecture are higher than with a gyroid architecture and are comparable to that of the сhronOS.

We aimed to investigate the effect of 8 weeks of moderate endurance training without considerable mechanical stress on the activation of extracellular matrix (ECM) gene expression in human skeletal muscles. Mechanical stress activates ECM biogenesis in the skeletal muscles, therefore aerobic exercise on a cycling ergometer with concentric muscle contractions only was used in the study. Skeletal muscle samples from m. vastus lateralis were taken from seven young untrained men before and after 8 weeks of aerobic training. Changes in the transcriptome (RNA sequencing) and proteome (shotgun quantitative proteomics analysis) were assessed in the samples; ECM-associated proteins (or matrisome) were determined using the Matrisome DB database. After the training period, a change (mainly an increase) in the content of 14 ECM proteins and 134 mRNAs of ECM proteins was found. The largest increase in protein content was found for collagens type 1 and 3 (1.7 and 2.2 times, respectively), the main proteins of the human skeletal muscle’s ECM, which was consistent with an increase in the corresponding mRNA by 10–20 times. In addition, an increase in the expression of more than a hundred mRNAs of collagens, glycoproteins, proteoglycans, and enzymatic regulators of ECM was found, which occurs simultaneously with an increase in the expression of genes of growth factors (IGF1, PDGFs, TGFB1, MDK, etc.), which play a main role in ECM biogenesis regulation. In conclusion, 8-week aerobic exercise training without considerable mechanical stress is a powerful stimulus for the activation of ECM biogenesis in skeletal muscle.

BACKGROUND: In recent years, the number of children with pectus carinatum tended to increase. The literature describes only a few cases of a combination of keeled chest deformity with a more serious pathology of the spine, i.e., ScheuermannMau disease. AIM: This study aimed to examine the frequency, clinical manifestations, and timely diagnosis of combined structural lesions of the thoracic spine in children with keeled chest deformity. MATERIALS AND METHODS: This observational single-center cross-sectional study included patients aged 517 years with pectus carinatum. Categorical values were described by indicating absolute values and percentages in the sample, and quantitative indicators with normal distribution were described using arithmetic means and standard deviations and 95% confidence intervals. Quantitative indicators without normal distribution were described using the median and interquartile range. RESULTS: ScheuermannMau disease was detected in 11 (9.3%) of 118 children with pectus carinatum. Pterygoid scapulae was noted in 97 (82.2%) children with pectus carinatum, increased cervical lordosis in 93 (79.7%), and sloping, anteriorly adducted shoulders in 99 (83.9%), which significantly hampered the clinical assessment of the extent of thoracic kyphosis. At the time of examination, a rigid thoracic kyphosis was formed in a 16-year-old boy. In younger children (514 years old), ScheuermannMau disease had no clinical manifestations and was detected only during screening X-ray examination, whereas in the older age group (1516 years), 3 of 4 adolescents complained of back pain. CONCLUSIONS: The frequency of ScheuermannMau disease in children with pectus carinatum exceeds the average prevalence in the population. In patients with keeled chest pterygoid scapulae, excess cervical lordosis, and rounded shoulders are associated with the difficulty of the assessment of the magnitude of thoracic kyphosis. Asymptomatic progression of ScheuermannMau disease is typical in younger children with pectus carinatum, and pain syndrome and the clinical picture of the disease develop only by the age of 1516 years. Thus, all patients with pectus carinatum and posture disturbance should undergo a screening X-ray examination of the thoracic and lumbar spine to detect ScheuermannMau disease and initiate treatment in time.

The commentary critically analyzes the strategy proposed by the authors of the article for performing osteosynthesis and describes the system of care for patients with fractures in Moscow. Operating rooms are divided into planned and emergency. And they, in turn, are divided into conventional and hybrid, in which it is simultaneously possible to perform endoscopic, endovascular, and open surgery. Surgeries are performed in order of priority. Highest priority: extra-focal fixation of limb bones and/or pelvis with ex-fix devices; surgery on extremities with impaired blood supply in the distal parts; decompressive fasciotomies with simultaneous external fixation of fragments in ex-fix devices with suspected formation of compartment syndrome; surgeries performed in patients with severe combined or multiple trauma. High priority: open fractures of type 3A and 3B according to the Gustillo classification, requiring primary surgical treatment of wounds and external fixation; closed unstable fractures.

Proximal femoral fractures (PFF) are one of the most common reasons for admission of patients to a traumatological and orthopedic hospital. For the vast majority of patients with PFF, such injury means a loss of the previous degree of mobility. Clinical guidelines are the main working tool of a practicing physician, both a specialist and a narrow practice doctor. Conciseness, structuredness of information about a particular nosology, methods of its diagnosis and treatment, based on the principles of evidence-based medicine, allow to give in a short time one or another answer to a question of interest to a specialist, to achieve maximum efficiency and personalization of treatment. These clinical guidelines include data on the classification, clinical presentation, diagnosis, and treatment of proximal femoral fractures. In addition, they provide methods for the rehabilitation of patients with this pathology.

Introduction Fractures of the distal metaepipheseal fractures of the radius (DMER) have a leading place in the overall structure of upper limb injuries. DMER fractures are frequently associated with soft- tissue injuries of the wrist joint, and namely, the triangular fibrocartilage complex (TFCC). The additional use of arthroscopy of the wrist joint in the treatment of patients with a DMER fractiures reduces the duration of recovery of patients and improves the result of their treatment. The aim of the study was to determine the effect of arthroscopic surgical treatment of TFCC injuries during bone osteosynthesis for DMER fractures on the functions of the upper extremities (extension/flexion of the hand, hand grip strength, pronation/supination of the forearm, DASH index). Materials and methods The study included 68 patients with DMER fractures, who were divided into 2 groups, depending on the treatment of the fracture. After reduction and osteosynthesis, all patients underwent arthroscopy of the wrist joint. If TFCC injury was detected, either a debridement or a TFCC suture was performed. Results TFCC injury was detected in 61.7 % (n = 42). Debridement was performed in 42.9 % (n = 18); suture using the inside-out technique was performed in 47.6 % (n = 20); one patient underwent reinsertion. After 6 months, the function of flexion and extension of the hand was significantly worse in patients with combined TFCC and DMER injuries, but after 12 months, the indicators were similar. The strength of the hand grip and the rotational function of the forearm did not differ between the subgroups. The subjective assessment of DASH after 6 months was worse in the group with TFCC injury, but after 12 months the results were similar. Conclusion Surgical treatment of TFCС injury in intraarticular fractures of the distal radius contributes to the restoration of the upper limb function to a premorbid level 12 months after surgical treatment.

Background. The currently existing techniques for dissection the anterior tibial vascular bundle in the proximal third of the lower leg do not provide sufficient length of the vascular pedicle to rotate the tibial bone graft to the level of the middle third of the thigh. The aim of the study to substantiate the possibility of pedicled transfer to the level of the thigh middle third of two blood-supplied bone autografts on a common permanent pedicle, including the anterior tibial vascular bundle. Material and Methods. The study was conducted on 62 lower limbs of non-fixed (native) corpses. We studied the topographic and anatomical relationship between the anterior tibial vascular bundle and the deep peroneal nerve at the level of the proximal third of the leg. Results. The distance between the tip of the greater trochanter of the femur and the distal edge of the anterior tibial bone graft using a combination of grafts at the same level in men was Me 176.7 [173.7; 193.9] mm, in women Me = 151.6 [146.9; 159.9] mm. An analysis of limb lengths ratios in men and women indicates standard level that can be achieved with graft rotation in each person. Conclusion. Dissection of the anterior tibial vascular bundle at the level of the proximal third of the lower leg allows rotation of the complex of the anterior tibial bone autograft and the autograft of the second metatarsal bone into the area of the middle third of the femur on a single vascular bundle. Prevention of injury to the deep peroneal nerve branches during dissection of the vascular pedicle requires the use of microsurgical techniques and preoperative preparation.

Introduction: Skeletal muscles damage (direct and vicarious) slows down the recovery processes in patients with injuries of the musculoskeletal system. It occurs in the early postoperative period as well. An increase in the rigidity of the skeletal muscle extracellular matrix can reduce pain, tissue swelling, and accelerate the recovery of contractility.Objective: The analyses of the effect of branched-chain amino acids (BCAAs) intake on the expression of IGF1 genes, type 1, 3 and 5 collagen, which are crucial in the composition of the skeletal muscle extracellular matrix, as well as on the muscle membrane damage against the background of chronic damage to skeletal muscles.Material and methods: 12 young healthy male subjects, skiers aged 19 (18; 22) received a placebo treatment (maltodextrin, 100 mg/kg body weight/day; n = 6) or a mixture of amino acids (leucine, isoleucine, valine – 50:25:20 mg/kg body weight/day respectively; n = 6). The treatment was received daily against the background of a large amount of aerobic high-intensity training (up to 22 hours per week). Before and after the amino acids intake a biopsy of the musculus vastus lateralis was performed, and venous blood samples were taken during the experiment.Results: The intake of leucine against the background of training led not only to a pronounced increase in the level of IGF1 protein in blood by 1.5 times (which corresponds to the literature data), but also to a trend towards an increase in the expression of IGF1Ea mRNA by 1.8 times in the skeletal muscle, and a decrease in the level of markers of muscle membranes damage – creatine phosphokinase (CPK) activity and myoglobin. In addition, changes in the IGF1-dependent collagen genes expression strongly correlated with changes in IGF1Ea expression, but not with IGF1 protein in blood (pooled group, n = 12). Thus, the intake of leucine as a part of the essential amino acids can reduce damage to skeletal muscles caused by excessive physical activity, lack of physical activity, or direct trauma.Conclusion: A 10-week BCAAs intake by individuals with documented chronic muscle membrane damage caused an increase of basal levels of IGF1 in blood and a trend towards increased IGF1Ea mRNA expression in skeletal muscle, and also caused a modest reduction in damage of skeletal muscle membrane.

Introduction Shoulder dislocation is one of the most common shoulder injuries and occurs in all age groups. Methods for diagnosing and treatment of the middle and older age groups patients with acute injury currently remain open. Surgical treatment is usually applied only in cases of chronic instability. However, conservative treatment in cases with a missed rotator cuff tear leads to a dysfunction of the shoulder joint and can lead to the development of chronic pain and recurrent shoulder instability. Therefore, it is necessary to develop an algorithm for diagnosing the rotator cuff tear and to find the most optimal methods for its surgical correction. The purpose of the study was to compare the results of conservative and surgical treatment in patients of the middle and older age groups after traumatic dislocation of the shoulder, accompanied by rotator cuff tear. Materials and methods The study is based on a prospective analysis of examination and treatment of 114 patients with shoulder dislocation aged 18 to 89 years. Among all patients with rotator cuff tear, 19 patients were selected for conservative treatment and 24 patients for surgical refixation of the rotator cuff tendons. Results The result of treatment was assessed 12 months after the surgical operation or the injury using ULCA shoulder score, DASH and ASES. It was found the scores of patients who underwent surgery for rotator cuff tear were significantly better than in the patients treated conservatively. Conclusion Therefore, all patients of middle and older age groups with dislocation of the shoulder should be examined for the presence of rotator cuff tear. In case the rotator cuff is torn, surgical treatment is preferred over conservative treatment.

Abstract. Introduction The problem of complications after surgical treatment of pertrochanteric fractures in elderly patients is relevant and far from a solution. Materials and methods The retrospective study was based on the analysis of the results of treatment of 129 patients with pertrochanteric femoral fractures (average age 76 years). All fractures in the early time from trauma were fixed with two types of cephalomedullary nails, either dynamic or static. All patients could not limit the load on the operated limb after surgery because of different reasons. Results The results of treatment were evaluated in 109 patients after one year. In dynamic cephalomedullary fixator group (59 patients), there were 7 orthopedic complications with a functional Harris scale result of 68 points (range, 26 to 94 points). In static cephalomedullary fixator group (50 patients), there were 14 orthopedic complications with a functional Harris score of 56.5 points (range, 15 to 92 points). Discussion Higher results of treatment in the group of dynamic fixator in the condition of full-weight bearing on the operated limb may be associated with the possibility of dynamization of the part of fixator in response to bone resorption in the contact area of bone fragments. The use of dynamic cephalomedullary fixators instead of static ones for treatment of pertrochanteric femoral fractures in elderly patients exercising full weight-bearing leads to a decrease in orthopedic complications (from 28 to 11.9 %) and improves the functional results of treatment.

Objective: Insulin-like growth factor I (IGF1) is an important regulator of collagen and extracellular matrix protein expression. We aimed to evaluate the effect of amino acids (AAs) on expression of IGF1 and IGF1-dependent genes in human myotubes and skeletal muscle and supposed that AAs administration increases IGF1 levels in blood and expression of IGF1 and IGF1-dependent genes in trained skeletal muscle, thereby reducing training-induced muscle damage. Design: Human myotubes were incubated with Arg and Leu for 24 h. Then, the effects of long-term branched chain AAs administration (10 weeks, 0.1 g/kg body mass/day) to volunteers (six subjects per AAs and placebo groups) performing large training volumes regularly (cross country skiers, training twice a day) were examined. Results: Incubating the myotubes with AAs increases expression of IGF1 mRNA isoforms and IGF1 secretion by 2-3 times. In athletes, long-term AAs administration increased basal blood levels of IGF1 (similar to 50%) and expression of IGFIEa mRNA slightly in skeletal muscle. There is no marked increase in expression of COL1A1, COL3A1, COL5A1, and LOX genes in skeletal muscle after AAs administration. However, expression of these genes in the combined group (placebo + AAs; n = 12) significantly correlated with the expression of IGFIEa mRNA in muscle and did not correlate with IGF1 levels in the blood. Conclusions: AAs administration increases IGF1 expression in vitro and in vivo. To obtain more pronounced changes in expression of IGF1 and IGF1-dependent genes in skeletal muscle, it may be necessary to increase the dose and/or duration of AAs administration.

Background. The lack of a system for evaluating the feasibility of new trauma and orthopedic departments in outpatient clinics under construction creating is one of the main reasons for the imbalance in their territorial location. Therefore, one of the most urgent modern tasks in the megalopolis healthcare organization — is to develop a system for effective regulation of the trauma and orthopedic outpatient departments network construction. The purpose of the study is to improve the effectiveness of outpatient trauma and orthopedic care for megalopolis residents. Materials and Methods. In the research process, theoretical (formalization, synthesis, deduction) and empirical (observation, comparison, modeling, measurement) methods were used. A total of 67 emergency trauma outpatient departments in Moscow were sampled and data on their attendance for April 2019 were collected. Results. Creation of a mathematical model of the network of outpatient primary trauma care and a basic algorithm for estimating the average time from the moment a patient received injuries to the time of primary care in one of the emergency outpatient trauma units of the medical organizations of the capital, which can be used by the executive bodies of the healthcare organization cities in solving administrative and economic problems. Conclusion. The developed specialized mathematical algorithm for assessing the existing effectiveness of the already existing emergency outpatient trauma units network and the distribution of new units allows you to create an “ideal” model for the location of these deparments in a megapolis. In the future, this model can be developed taking into account the development of the transport network, the financing of emergency rooms, etc.

Polyethylene glycol diacrylate-based hydmgels filled with calcium phosphates (CaP, Ca/P < 1.5) were stereolithographically fabricated as three-dimensional permeable biocomposites for bone tissue regeneration, probed by several instrumental techniques (including scanning electron microscopy, infrared and UV-vis spectroscopy), and subjected to rheological/mechanical property analysis. As the CaP content increased from 0 to 10 wt%, Young's modulus and mechanical strength increased from 4 to 11 kPa and from 34 to 167 kPa, respectively. Moreover, the enhanced elastic properties and tuneable swelling behaviour of the fabricated composites made them well suited for bone defect filling.