Object: long bone distal metaepiphysis fractures. Aim: to improve the results of the treatment of long bone distal metaepiphysis damages by applying objective criteria for making tactical decisions, in accordance with the principles of biological fixation. Methods: retrospective clinical studies, biomechanical, experimental biological studies on laboratory animals, clinical and experimental study of micro-rupture of bone fragments, clinical, radiological, computed tomography, technologies for evaluating clinical results, statistical. On the basis of retrospective clinical studies, for the first time, quantitative and qualitative relationships have been established for the treatment technologies for fractures of the distal metaepiphysis of long bones, which are used today (internal fixation – 61 %, external – 20 %, fixation method and skeletal traction – 19 %). Such a tactical approach made it possible to obtain good results in 44 % of cases, satisfactory – 24 %, unsatisfactory – 32 %. It has been proven that unsatisfactory results are primarily caused by complications due to unreasonable expansion of indications for the use of internal fixation methods. By means of biomechanical studies of mathematical models of fractures of the distal femoral metaepiphysis, the advantages of external osteosynthesis in the case of a C1 fracture have been proved, and in the case of C3 fractures, extrafocal osteosynthesis turned out to be more effective. For the first time in a clinical study, it was proved that during the first 10 weeks after performing extrafocal osteosynthesis, the amplitude of mutual displacements of tibial fragments decreased from (2.3 ± 0.2) mm to (0.8 ± 0.2) mm. It has been established that the use of one-sided rod devices makes it possible to obtain reliable fixation of bone fragments together. In in-vivo experiments, it has been proved that in case of intra-articular injuries of the distal metaepiphysis of long bones, when using closed technologies of reposition and fixation of fragments, functional treatment should be started no earlier than the beginning of the fifth and no later than the sixth week after injury. Based on the results of retrospective and prospective clinical studies, the theory of an individual approach to the choice of methods for the treatment of fractures of the distal metaepiphysis of long bones using biologically justified technologies was developed, due to which the overall treatment results were significantly improved, and the percentage of complications after surgical interventions was significantly reduced. Effective technologies for the treatment of lesions of the distal metaepiphysis of long bones, which provide optimal functional results, have been proposed. The expediency of a wider use of conservative treatment methods (fixation and skeletal traction) and the method of external fixation by rod devices has been proven. This made it possible to significantly reduce the number of unsatisfactory results, in particular, purulent-necrotic complications and disorders of bone regeneration. Reasonable indications for open reduction and internal fixation, which provide for careful preoperative planning, taking into account not only the formal classification signs of a fracture, but also the individual characteristics of the injury and the patient. It has been proved that in case of type C1 intra-articular injuries, preference should be given to extra-focal osteosynthesis, and in the case of multiple fractures and impression damages of the C3 type articular surface, extrafocal fixation should be performed. The technologies of extrafocal osteosynthesis, as well as reasonable indications for conservative and surgical methods of fixation, which allow for an individual approach, choose the optimal treatment tactics and improve the quality of treatment of patients with fractures of the distal metaepiphysis of long bones have been developed. The use of the proposed provisions regarding functional treatment, taking into account the dynamics of changes in the amplitude of mutual displacements of bone fragments and pre-pain loads on the damaged segment under conditions of stabilization with external fixation devices, allows the implementation of the effect of functional remodeling, and the use of orthoses based on Softcast and Scotchcast materials allows avoiding secondary displacement of fragments and obtaining positive medical and social effect. The results of the study were introduced into the clinical practice of the SI "Sytenko Institute of Spine and Joint Pathology of the National Academy of Medical Sciences of Ukraine", specialized traumatology departments in Kharkov and the region, in the educational process at the departments of traumatology and orthopedics of the Kharkiv Medical Academy of Postgraduate Education of the Ministry of Health of Ukraine, Kharkiv National Medical University. Traumatology and Orthopedics.
