• Composites Research
• /
• v.12 no.5
• /
• pp.98-109
• /
• 1999

An investigation has been performed to develop a nonlinear finire element method for the analysis of the long-term behavior of an artificial hip joint. The three dimensional multi-layered brick element is used to analyze the design performances of hip prodtheses with various materials and the thick laminated composite hip prostheses with various layup sequences. The used element can accommodate the varying material properties of the element and allow the ply-drop-off along the eleement edge. The nonlinear finite element analysis program has been verified by the comparison with the exact solution of the bean problem subjected to uniaxial loading. By using the program, the density changes and strength ratios of artificial hip joint are calculated according to the hip prosthesis materials and the layers of composite hip prosthesis. The numerical results are easily applied to evaluate design performances of a hip prosthesis, and decrease the difficulty and time of hip prosthesis design.

• Journal of Biomedical Engineering Research
• /
• v.23 no.2
• /
• pp.119-130
• /
• 2002

The nonlinear finite element program has been developed to analyze the design performance of an artificial hip prosthesis and long term behavior of a treated femur with stems made of composite material after cementless total hip arthroplasty(THA). The authors developed the three dimentional FEM models of femoral bone with designed composite stem which was taken with elliptic cross section of 816 brick elements under hip contact load and muscle farce in simulating single leg stand. Using the program, density changes, stress distributions and micromotions of the material femoral bone were evaluated by changing fiber orientation of stems for selected manufacturing method such as plate cut and bend mold. The results showed that the composite materials such as AS4/PEEK and T300/976 gave less bone resorption than the metallic material such as cobalt chrome alloy, titanium alloy and stainless steal. It was found that increasing the long term stability of the prosthesis in the femur could be obtained by selecting the appropriate ply orientation and stacking sequence of composite.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2021.05a
• /
• pp.470-473
• /
• 2021

In this study, we developed the biometric ultrasound transducer, residual thickness measurement algorithm and optimized ultrasound operation methods to diagnose precise conditions of implanted medical prosthetic material inserted during total hip artificial joint replacement. In detail, ultrasound transducers having 8 MHz and 20 MHz center frequencies with similar sensitivity and bandwidth were fabricated to measure various thicknesses of commercial polyethylene-based artificial hip liners, resulting in a comparative analysis of signal-to-noise ratio and axial resolution to conduct an optimization study of ultrasound operations in vivo.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.24 no.2 s.173
• /
• pp.329-337
• /
• 2000

An investigation has been performed to develop an analysis tool based on a nonlinear beam theory, which can be used to predict the long-term behavior of an artificial hip joint. The nonlinear behav ior of the femur arise from the coupled dependence of the bone density and the mechanical properties on each other. The beam theory together with its numerical algorithm is developed to take into account the nonlinear bone remodeling process of the femur that is long enough to be assumed as a beam. A piecewise linear curve for the bone remodeling rate is used in the bone remodeling theory and the surface area density of bone is modeled as the third order polynomial function of bone density. At each section of the beam, a constant curvature is assumed and the longitudinal strains are also assumed to vary linearly across the section. The Newton-Rhapson iteration method is used to solve the nonlinear equations for each cross section of the bone and a backward method is used to march along the time. The density and the remodeling signal ar, calculated along with time for the various time steps, and the developed beam theory has been verified by comparing with the results of finite element analysis of a remodeling bone with an artificial hip joint of titanium prosthesis subjected to uni-axial loads and pure bending moment. It is concluded that the developed beam theory can be used to predict the long-term behavior of the femur and thus to design the artificial hip prosthesis.