Gonarthrosis is one of the topical orthopedic problems. One out of three all orthopedic patients are affected by knee osteoarthritis. Multiple studies demonstrate that this condition occurs most frequently in working-age population. Having studied the results of surgical treatment in 324 gonarthrosis patients, we have elaborated a differentiated approach to knee arthroplasties. A unicondylar arthroplasty is expedient for young patients; if flexion contracture of a knee exceeds 15°, we recommend a PLC non-preserving prosthesis; if a lesion of a tibial process exceeds 10 mm, we used a prosthesis with a tibial extensor; for total instability of knee, we used hinge-type constrained modifications of prostheses.

Background: Some biochemical indicators in patients with disorders of reparative osteogenesis were described in a sufficient number of studies, but the role of factors affecting the metabolism of bone tissue and the ways of their correction are not sufficiently studied .. For effective prediction of the course of reparative osteogenesis in fractures, it is important to identify early markers of impaired consolidation and, accordingly, its pathogenetic correction. Purpose: to determine biochemical indicators of the course of reparative osteogenesis in patients with multiple and monolocal fractures of the bones of the lower limb. Materials and Methods: 44 patients aged 23 to 47 years were examined. To assess the ratio and intensity of the processes of biosynthesis and breakdown of collagen, as the major structural protein of connective tissue, the following indicators were determined in the blood serum of patients: fractions of hydroxyproline, oxyproline, collagenase, cathepsin B, elastase, proteolysis-antielastase inhibitors. In addition, indicators of mineral metabolism were also determined in the blood serum of patients: the content of calcium, phosphorus, alkaline phosphatase activity. Results: A comparative analysis and comparison of the results of the biochemical examination of patients with closed tibial fractures and multiple fractures revealed that already at the beginning of the research, deviations from the norm in the indicators of both mineral and collagen metabolism were observed. Both groups of the patients are characterized by the presence of disturbances in the ratio between calcium and phosphorus, and in patients with multiple fractures - an increase in the level of alkaline phosphatase. The detected changes in the mineral metabolism in patients with multiple fractures had a more pronounced and intense character due to the multiple injuries and presence of a large number of destroyed cells in the first days after the injury. Conclusions: Indicators of the unfavorable course of reparative osteogenesis in patients with bone fractures are a decrease in the content of calcium/phosphorus in blood serum, an increase in the level of free oxyproline and collagenolytic enzymes (collagenase, elastase, cathepsin B). Besides, there is a decrease in the level of proteolysis inhibitors (antielastase, 2-macroglobulin) and a decrease in suspension stability and antioxidant activity, increase in blood fibrinolytic activity. Our findings justify the need for prophylactic drugs that improve reparative osteogenesis soon after the injury (within a month) in patients with multiple fractures in order to activate the processes of reparative regeneration.

Aim: To justify the choice of a method for fixing unstable proximal tibial fractures (PTF), to conduct computer simulation of stresses on various metal fixators. Materials and Methods: at the initial stage, a solid 3D model of the lower leg has been created using Solid Works, on the background of anatomical models and CT scans. The model contained the following elements: tibia and fibula, interosseous membrane, ligaments of the proximal and distal tibia syndesmosis, and a modeled proximal tibial fracture. We have subsequently studied 4 models of bone fragments’ fixation with LCP plates and an intramedullary blocking metal rod. Further calculations were performed using the finite element method. Results: computer simulations of stresses on various metal fixators applied to fix a PTF convincingly proved that blocked intramedullary osteosynthesis (BIOS) and LCP plates placed bilaterally are feasible for this category of patients. Conclusions: Deformities and loads observed in the metal fixator, bone tissue and ligamentous apparatus run within normal limits. They are statistically significantly (p ≤ 0.05) lower in models of bone fragments’ fixation with IM nailing and bilaterally placed LCP plates. This evidences the adequate stability of bone fragments’ and these methods of osteosynthesis as a whole, compared to the stains in the same elements of modelled fixation using only one plate – medially or laterally. The results of the study may serve as the background for the development of an algorithm for surgical treatment and rehabilitation of patients with PTF.

he article reports on the effectiveness of various types of surgical interventions for gonarthrosis in the system of staged treatment of patients with osteoarthritis of the knee joint. The first group consisted of 23 patients who underwent arthroscopic revision, debridement of the knee joint with subsequent corrective osteotomy of the tibia or femur due to gonarthrosis. The second group consisted of 22 patients who underwent unicondylar endoprosthesis of the knee joint due to gonarthrosis. The third group consisted of 47 patients who underwent total knee arthroplasty. As a result of surgical treatment of patients with osteoarthritis of the knee joint, it was established that arthroscopy, debridement followed by corrective osteotomy give a good effect and help prepare the joint for further endoprosthetics. Single-condylar endoprosthesis is the operation of choice for patients with an isolated lesion of only one of the knee joints, enabling to preserve enough high level of physical activity. Whereas total endoprosthesis of the knee joint in patients with gonarthrosis III - IV stages allows to achieve positive treatment results in 93.2% of patients and is an effective surgical intervention that allows to significantly reduce the pain syndrome, improve the function of the knee joint and thereby improve the quality of life in this category of patients.

Summary. Removal of metal fixators today is one of the most common surgical interventions in developed countries. According to many European researchers, surgeries performed to remove metal fixators account for almost 30% of all planned surgical interventions and 15% of the total number of surgeries performed in trauma departments. This certainly indicates the great social significance of the problem. An analytical review of the literature has shown that the surgery of removing metal fixators in the consolidation of bone fractures is not a routine procedure; it requires experience and training of the surgeon. The problem of removal of metal fixators in some individual cases and localizations is not completely solved and requires further clinical and experimental studies.