Reducing Contact Stress of the Surface by Modifying Different Hardness of Femoral Head and Cup in Hip Prosthesis

Abstract

The wear of hip prosthesis due to applied load and sliding distance during the patient's daily activity cannot be avoided. Wear causes osteolysis or metallosis due to the wear debris produced by the wear process. Several methods were used to reduce wear in metal-on-metal hip prostheses. One of the efforts performed to reduce wear was the differential-hardness concept. Based on the literature, the fine surface roughness of the femoral head are the reason why the hip prosthesis with differential-hardness reduces wear. Besides, the differential-hardness will contribute to the difference of modulus elasticity then influenced the contact stress on the surface contact. According to Archard's wear law, wear on the material pair is affected by contact stress. Therefore, the analysis of contact stress on the hip prosthesis with differential-hardness is important to investigate. The investigation performed by the static contact of two-dimensional axisymmetric with frictionless by using finite element simulation. The simulated models are the alumina vs. alumina, alumina vs. SS316L, CoCr vs. CoCr, CoCr vs. SS316L, and SS316L vs. UHMWPE. The purpose of this study is to determine the contact stress on the surface contact due to differential-hardness of the femoral head and cup. The results of simulations show that the differential-hardness marked by differences in the modulus of elasticity can reduce the contact stress on the surface contact if compare with the similar hardness.

Polycrystalline Diamond as a Potential Material for the Hard-on-Hard Bearing of Total Hip Prosthesis: Von Mises Stress Analysis

“…The current von Mises stress results from the computational simulation of hard-on-hard bearings of total hip prosthesis need to be validated to ensure the accuracy of the results obtained in previous studies under identical conditions and parameters [ 41 ]. The highest von Mises stress (in the 7th phase of the gait loading) for the CoCrMo-on-CoCrMo bearing was validated by the previous research by Saputra et al [ 24 ] presented in Figure 5 . The difference of the highest von Mises stress result from both of them is 4.9 MPa indicating a difference of around 8.78%.…”

“…The computational simulation of the von Mises stress of the hard-on-hard bearings was conducted using ABAQUS CAE version 6.14-1 (Dassault Systèmes, Vélizy-Villacoublay, France) with the consideration of two main components, namely acetabular cup and femoral head to simplify the modelling as shown in Figure 2 . The finite element model of the hard-on-hard bearings adopts a 2D axisymmetric, as previous researched by Saputra et al [ 24 ]. The definition of contact is configured of the contact surface of femoral head as master surface, while the contact surface of acetabular cup as slave surface.…”

“…A computational study of the von Mises stress on the bearings of total hip prosthesis via finite element method has been previously reported by Saputra et al [ 24 ] by who studied different combinations of bearing materials, both hard-on-hard and hard-on-soft such as Al 2 O 3 (aluminium oxide)-on-Al 2 O 3 , Al 2 O 3 -on-SS 316L (stainless steel 316L), CoCr (cobalt chromium)-on-CoCr, CoCr-on-SS 316L, and SS 316L-on-UHMWPE (ultra-high molecular weight polyethylene). Furthermore, Kalayarasan et al [ 25 ] also analyzed the von Mises stress on CoCr-on-UHWMPE, CoCr-on-CoCr, CoCr-on-CoCrMo (cobalt chromium molybdenum), and CoCr-on-Al 2 O 3 bearings.…”

Adopted walking condition for computational simulation approach on bearing of hip joint prosthesis: review over the past 30 years

“…[ 71 ] Full cycle − Saputra et al. [ 104 ] ABAQUS Total hip arthroplasty Contact pressure and von Mises stress Simplified walking condition Static load Paul [ 64 ] No motion − Peak loading - Shankar et al. [ 105 ] ANSYS v. 14.0 Total hip arthroplasty Contact pressure and wear Simplified walking condition Static load Bergmann et al.…”

“…[ 50 ], Jamari et al. [ 65 ], and Saputra et al [ 104 ]. However, by using a three-dimensional finite element model without axisymmetric simplification, many researchers still simplify the adoption of walking conditions by not considering the motion component that can be found in the literature by Barreto et al.…”