Design of new generation femoral prostheses using functionally graded materials: A finite element analysis

Abstract

This study aimed to develop a three-dimensional finite element model of a functionally graded femoral prosthesis. The model consisted of a femoral prosthesis created from functionally graded materials (FGMs), cement, and femur. The hip prosthesis was composed of FGMs made of titanium alloy, chrome-cobalt, and hydroxyapatite at volume fraction gradient exponents of 0, 1, and 5, respectively. The stress was measured on the femoral prosthesis, cement, and femur. Stress on the neck of the femoral prosthesis was not sensitive to the properties of the constituent material. However, stress on the stem and cement decreased proportionally as the volume fraction gradient exponent of the FGM increased. Meanwhile, stress became uniform on the cement mantle layer. In addition, stress on the femur in the proximal part increased and a high surface area of the femoral part was involved in absorbing the stress. As such, the stress-shielding area decreased. The results obtained in this study are significant in the design and longevity of new prosthetic devices because FGMs offer the potential to achieve stress distribution that more closely resembles that of the natural bone in the femur.

Neck fracture of femoral stems with a sharp slot at the neck: biomechanical analysis

“…This stress concentration at the sharp corner was excessively high. As the stress at the smooth corner was equivalent to that previously reported under similar experimental conditions [29], the sharp corner possibly led to this high stress concentration. These results indicated that the neck of the fractured stem might be exposed to stress above the fatigue strength of Ti-6Al-4V.…”

Comparison of Various Functionally Graded Femoral Prostheses by Finite Element Analysis

“…The locations of the applied forces are shown in Figure 2. The femur was fixed at the distal end of the knee joint (Figure 1) [30, 39]. The bone and the cement layer were bonded in the cemented prosthesis implantation [40].…”

“…They found that the FG prostheses preserved the host bone better than the prostheses with conventional materials owing to having more mechanical stimuli, more uniform interface shear stress, and smaller maximum interface stress. A three-dimensional FEA was conducted by Oshkour et al [30] to determine the performance of cemented FG prostheses with a longitudinal gradient direction during a gait. They found less stress in the FG prostheses and more stress develops in the bone and the cement.…”

A comparative finite element analysis of two types of axial and radial functionally graded dental implants with titanium one around implant-bone interface

“…FGBM is a nonhomogeneous biomaterial composed of bioceramic and biometal; its properties such as elasticity modulus, mass density, and thermal conductivity vary smoothly and continuously through the biomaterial. Due to the high applicability of FGBM composite biomaterials, a number of researches have been dedicated many times to the biomedical applications of FGBM composites [11][12][13][14][15][16]. In the case of dental implants, FGBM is usually considered to comprise a mixture of titanium and bioactive hydroxyapatite (HA) due to its biocompatibility, bioactivity, and structural resemblance to that of the organic part of the teeth and body bones.…”