Bilostotskiy A. Clinical and biomechanical substantiation of a choice of tactics of surgical treatment of patients with nonunion and delayed union around the knee joint

Object: Clinical forms of the violations of fractures consolidation: delayed union, nonunion and, incomplete fracture, pseudarthrosis in the distal femur. The aim: to improve the results of treatment by developing, substantiating and introducing into clinical practice the integrated differentiated treatment program for patients with disorders of consolidation after distal femur fractures. Methods: clinical, radiological (X-ray, computer tomography, densitometry), Doppler, statistical and mathematical (finite element method). As a result of the conducted experimental studies for the first time data on the stress-strain state of the osteosynthesis model of the nonunion of the distal femur with different fixation variants and different localization of the fracture line and the contact area of the fragments were obtained. During the biomechanical experiment new knowledge about the load distribution and rigidity of the "bone - fixing device" system were obtained. It was shown that as the contact area between the fragments increases, the stress in the bone tissue and fixing elements decreases, the rigidity of the system "bone - fixing device" increases; with all variants of localization of nonunion and regardless of the size of the contact area of the fragments, the rotational load causes the greatest stress in the fixing elements and bone tissue in comparison with the axial and flexural load in all the considered models. In the case of nonunion location in the epiphysis or metaepiphysis of the femur (the distance of the nonunion line to 6 cm from the upper edge of the lateral femoral condyle), the smallest stress of the cortical and spongy layers with the greatest For the first time, a complex differentiated approach to the treatment of this category of patients was developed and scientifically substantiated taking into account the clinical and radiological characteristics of a particular disorder of the fracture consolidation. The method of choosing the tactics of surgical treatment of patients with disorders of consolidation of the distal femur fractures was developed. The proposed method makes it possible to select a metal fixator, the technique of osteosynthesis and to determine the indications for bone grafting. The program of physical rehabilitation of patients with a knee joint disfunction after surgical intervention on the distal femur was developed. This program allows us not only to increase the volume of motion in the knee joint, but also to restore its function, limb functionality and patient working capacity. The results of the research were introduced into the clinical practice of the department of traumatology No. 2 of the Kharkiv public health care institution "Emergency Hospital named A.I. Meshchaninov", the department of traumatology of Kharkiv public health care institution "Regional Clinical Hospital - Center for Emergency Medical Care and Medicine of Disasters", departments of the rehabilitation and emergency trauma and rehabilitation surgery of SI "Sytenko Institute of Spine and Joint Pathology National Academy of Medical Sciences of Ukraine", the department of traumatology Poltava public health care institution "Regional Clinical Hospital named after N.V. Sklifosovsky", the department of traumatology of Kharkiv municipal public health institution "Kharkiv city clinical multidisciplinary hospital No. 17". Traumatology and Orthopedics.