The Effect of Gunshot Injuries of the Bone Tissue on Its Mechanical Characteristics

The results of a developed full-scale biomechanical bench test procedure are analyzed, which makes it possible to determine the changes in the mechanical characteristics of the bone tissue in the linear deformation portions before and after gunshot fracture. Based on the research results, it has been found that the changes in the biomechanical characteristics of the bone tissue after gunshot fracture result from the formation of a shock wave osteoporosis zone and decrease linearly with increasing distance from the long bone defect in the wound zone. An experimental method for assessing the optimal location of devices for the external fixation of gunshot fractures of human long bones is considered. It is proposed to test a natural shinbone specimen with a standard pin fixator for fractures mounted on it. Four load types were used: compression, bending along the plane of the pins, bending across the plane of the pins, and torsion. The stiffness characteristics for different types of location of the pins are compared. Based on the results obtained, a method for the experimental determination of the stiffness of the system is described. The optimal location of the pins for the fixation of gunshot fractures of human long bones for each load type has been determined. The location of the pins for use on real patients is proposed. Mechanical tests of human shinbones have been carried out. A new method for the evaluation of changes in the properties of the bone tissue after gunshot fracture is proposed. The optimal location of the pins for the fixation of human long bones in the case of gunshot fractures has been determined.