Petrenko D. Preventive maintains of early aseptic instability of the hip endoprosthesis stem

3. Object of research-early aseptic instability of the hip endoprosthesis stem. The purpose-to maintain prophylaxis of early aseptic instability of the hip endoprosthesis stem by defining optimal model and the size of the standart implant with method of selection and criteria of selection. Methods of research-for defining of diagnosis and estimation of the total hip replacement results have benn used clinical methods,for developing of femur bone model-roentgenologacal mathod and computer tomography, for estimation of strain distribution in system "femur bone-implant" final element method, for statistic analysis program Mathcad 2001i Professional.On the basis of investigation of the strain distribution in the developed final-element model of the proximal femur with implant have been revealed that trough percent of contact between stem and bone tissue is 60%. This account allows to obtain primary stabilisation of the implant in femoral bone channel. That's why we have chosen a percent of contact like criteria of the implant selection. On the basis of this criteria we developed the method of hip endoprosthesis's stem selection. The method was introduced in the clinical practice of: Sytenko institute of spine and join pathology, Kharkov's regiomal traumatological hospital, regional hospital in Poltava. Method presented in department of traumotology and orhtopedics of Kharkov medcal state university and in department of traumotology, orhtopedics and combustiology of Kharkov medical academy of aftergradual education.Traumatilogy and orthpedics.