A Comparative Study on Wear Behavior of Hip Prosthesis by Finite Element Simulation

Abstract

A numerical approach was proposed to investigate the wear behavior occurred in the artificial hip joints in this paper. In the numerical simulations, the wear coefficients taken from pin-on-disk tests were introduced into the wear analysis model to assess the wear rates of polyethylene acetabular cups against metallic or ceramic femoral heads. For the established material combinations, different values of polyethylene wear rates were obtained respectively, which were not necessarily the realistic one as expected in vivo but could be confirmed after further discussion on the wear mechanism involved in wear tests. Current results indicated that the polyethylene/ceramic couples represented better wear performances than the polyethylene/metal couples. Furthermore, the ratio of wear rates for polyethylene cups against alumina and the metallic femoral heads was 0.5, which agreed well with that deduced from clinical studies or laboratory hip simulators. It is obvious that these comparable wear behaviors observed from clinics or laboratory studies also can be found by means of the numerical simulation.

Towards the optimal design of an uncemented acetabular component using genetic algorithms

“…These results suggest that Downloaded by [University of Nebraska, Lincoln] at 17:09 29 September 2015 apart from implant material, the thickness of the acetabular component plays a crucial role in implant-induced bone adaptation. The volumetric wear reduced with increasing in cup thickness (reduction in bearing diameter) (Table 3), which was comparable to previous studies (Maxian et al 1996a;Hung and Wu 2002;Bevill et al 2005).…”

“…H i is the wear depth for each element integration point and k w is the wear factor, which is dependent on the articulating materials and working conditions (Hung and Wu 2002). The values of wear factors used in this study are presented in Table 2.…”

“…In addition to the implant material, the thickness of the acetabular component influences the bone remodelling process and volumetric wear. An increase in thickness exacerbated bone resorption but led to decreased volumetric wear (Maxian et al 1996a;Hung and Wu 2002;Bevill et al 2005;Ghosh and Gupta 2014). Hence, optimal selection of the material and thickness of the acetabular component is necessary to minimize the effects of bone resorption and volumetric wear.…”

Life Estimation of Hip Joint Prosthesis

“…Wear coefficient is determined from pin on disk experiment [7] and for CoCrMo-UHMWPE combination, it is 3.5E -7 mm 3 /Nm. Using this wear constant, the calculated maximum contact pressure (r = 14.02 MPa) and assuming no change in socket geometry, wear depth (dh) can be estimated for known sliding distance (ds).…”

“…This number has steadily increased over the past 20 years, and is expected to continue to increase over the next several decades [2]. Failures of hip prosthesis have been reported due to fatigue failure of hip joint stem [3,4], fracture of bone cement [5] and wear caused by sliding present between head and socket [6,7]. In other words fatigue fracture and wear are the basic mechanisms associated with failure of hip prosthesis [8].…”