Work

Modern possibilities of traumatology and orthopedics are based on scientific achievements in the field of medical sciences, biomechanics and materials science.In case of femoral neck fractures and dislocations, post-traumatic arthrosis, congenital dysplastic arthrosis and systemic diseases, treatment is possible only by complete replacement of joint with an endoprosthesis.Reasonable choice optimal types of endoprostheses requires their evaluation in terms of not only clinical but also mechanical parameters.Main problem with use endoprostheses is the mismatch between the modulus of elasticity of bone and implant, which slows down regeneration and osteointegration.The modulus of elasticity metallic materials is 10-20 times higher than that of bone tissue, solution to this problem is possible by reducing modulus of elasticity through use of low-modulus alloys and surface modification of endoprosthesis.One of methods of modification is coating of endoprosthesis by gas-thermal spraying, the modulus of elasticity of such coatings can be reduced by an order of magnitude, depending on spraying mode.Increasing porosity of coating reduces its modulus of elasticity and increases strength of adhesion due to germination of bone tissue in the rougher microrelief.Excessive porosity reduces strength of coating and can lead to premature failure and surgery.Approximation of modulus of elasticity of coating is possible only to a certain limit value, above which the strength of coating will be insufficient in relation to the strength of bone. Influence of technological parameters of coating process on its physical and mechanical characteristics has studied superficially, task of study is to establish the functional dependences of modulus of elasticity on its porosity.Establishment of these dependences will allow by adjusting the parameters of the spraying mode to obtain the predicted modulus of elasticity of the coating with an optimal porous structure and sufficient cohesive strength.