The paper presents mathematic-statistic methods defining the influence of stress on ceramic elements’ durability of hip and knee joints endoprostheses. The tests were conducted with Finite Elements Method in the ADINA System. The obtained results state the influence of load on the values of durability and stress, that get formed in ceramic parts of joints, and help to detect and solve technical problems and thus, counteract the subsequent effects resulting from premature wear of endoprosthesis elements. The paper emphasizes necessity of discovering new materials, that will be bio-compliant and wear resistant. Although ceramic materials like Al2O3, ZrO2, are brittle and less resistant to load than metallic implants, their improving mechanical parameters (excellent tribological properties), make them becoming new standard in biomaterials for clinical use. That opens new possibilities especially for hip or knee joints alloplasty.

The paper presents Finite Elements Method numerical analysis of strength of friction pairs most often used in hip and knee joints alloplasty. Analytic solutions are to indicate and define the areas where damages or premature wear of cooperating elements may occur. Analytical-experimental research states complete and thorough analysis. Accurate technical simulation of the joints of the human motor system, is difficult to conduct due to high level of complexity of human bio-bearings. All attempts to simulate the work of human joints, lead only to an approximate reflection of real human joint motion. To properly face the above problems, along with numerical analysis, there have been conducted empirical tests on the simulator of knee joint endoprosthesis

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.

The article has been devoted to issues connected with the alloplasty and hip joint endoprostheses, that elements are being developed, which is supported by strength, tribological tests on used biomaterials, incl. polyethylene or computer modelling based on e.g. finite element method (FEM). In this paper, the results of research on the impact of the material articulations of the system head – acetabular and friction conditions on strength parameters of polyethylene components in the hip joint endoprosthesis. Numerical analysis of this friction node was carried out, using the ADINA System computer program and the simulations were performed at various friction conditions for metal/ polyethylene and ceramic/ polyethylene articulations with various UHMWPE modifications. The simulations results have shown the influence of tested material associations and friction conditions on parameters related to the strength of polyethylene cups, i.e. their displacements, stresses and deformations.

Engineering plays a significant role in the advancement of medicine. One example of this is endoprostheses, which are prostheses implanted inside the body. Hip joint endoprostheses are commonly implanted nowadays, greatly improving physical fitness and the associated quality of life. However, a potential risk in using such endoprostheses is the possibility of dislocation. In this presented work, systems of forces acting on the limb were subjected to analysis, identifying unstable states that increase the risk of dislocation. Most of the analyses are qualitative, presenting rather than solving the problem. Nevertheless, a quantitative approach was presented for the case of dynamic forces generated during kicking a soccer ball. For this purpose, computer simulation was employed, based on an appropriate mathematical model.