This paper presents a preoperative hip reconstruction method with diagnosed osteoarthritis using Durom Hip Resurfacing System (DHRS). The method is based on selection and application of the resurfacing to the pelvis reconstructed on the basis of computed tomography. Quality and geometrical parameters of distinguished tissues have a fundamental significance for locating and positioning the acetabular and femoral components. The application precedes the measurements of anatomical structures on a complex numerical model. The developed procedure enables functional selection of endo-prosthesis and its positioning in such a way that it secures geometric parameters within the bone bed and the depth , inclination angles and ante-version of the acetabular component, the neck-shaft angle and ante-torsion angle of the neck of the femoral bone, and reconstruction of the biomechanical axis of the limb and the physiological point of rotation in the implanted joint. Proper biomechanics of the bone-joint complex of the lower limb is determined by correlation of anatomical-geometrical parameters of the acetabular component and parameters of the femoral bone.
This article presents the results of investigating the influence of tooth contact ratio in helical cylindrical gears on vibroactivity of the gearbox. Based on the measurements carried out on a laboratory test stand, time-domain and frequency-domain start-up characteristics of vibrations and acoustic pressure were determined, and vibroactivity was assessed for a gearbox in which 4 pairs of gears were successively mounted with different face contact ratios equal to, respectively, epsilon beta=1,001; 1,318; 1,574; 2,636.
This elaboration presents the method of virtual positioning of the construction of an endoprosthesis of hip joint in a patient’s pelvis and femoral bone, reconstructed on the basis of imaging obtained from computer tomography. It is based on the matching of an implant to individual anatomical-biomechanical conditions. The method is established on the following procedures: diagnostic, spatial modeling, virtual measuring and targeted biometrological application for the model of bone structures. The final effect of the completed procedures is selection and optimal positioning of the endoprosthesis of hip joint before a planned medical intervention. The determined geometrical parameters of bone structures and settled positioning of the endoprosthesis can create data for the system of computer navigation.