Wear Analysis of Extracted Polyethylene Acetabular Cups Using a 3D Optical Scanner

Wear Analysis of Extracted Polyethylene Acetabular Cups Using a 3D Optical Scanner

Scopus Article

Wear analysis of total hip replacements (THR) is considered as one of the most relevant research areas helping to improve the longevity and the overall design of the THR. The co-ordinate machine method (CMM) andFourier profilometry are the most common methods for measuring the THR wear today. This paper presents optical scanner digitalization as a new method for measuring the wear of polyethylene acetabular cups. The aim of this paper is to explore the potential of this method for the polyethylene wear measurements. Optical scans for the purposes of this study were produced by the 3D optical scanner ATOS Triple Scan. The optical scanner is efficient and it can measure a large number of points for polygonisation and for further development of the pre-worn models. In this study, the scanner first generated point clouds on a sample of 13 retrieved UHMWPE acetabular cups. Next, volumetric models of the cups were created by polygonising the point clouds. Reverse engineering was used to develop models of the original acetabular cups using the geometry of the unworn parts of the retrieved cups. A comparison of the two models then showed the total volume of the polyethylene debris. The optical scanning method was validated against the gravimetric method using three new acetabular cups that were worn out on a hip pendulum simulator. Validation shows that the optical scanning method is a valid method for wear analysis of the retrieved UHMWPE acetabular cups.

Wear analysis of total hip replacements (THR) is considered as one of the most relevant research areas helping to improve the longevity and the overall design of the THR. The co-ordinate machine method (CMM) andFourier profilometry are the most common methods for measuring the THR wear today. This paper presents optical scanner digitalization as a new method for measuring the wear of polyethylene acetabular cups. The aim of this paper is to explore the potential of this method for the polyethylene wear measurements. Optical scans for the purposes of this study were produced by the 3D optical scanner ATOS Triple Scan. The optical scanner is efficient and it can measure a large number of points for polygonisation and for further development of the pre-worn models. In this study, the scanner first generated point clouds on a sample of 13 retrieved UHMWPE acetabular cups. Next, volumetric models of the cups were created by polygonising the point clouds. Reverse engineering was used to develop models of the original acetabular cups using the geometry of the unworn parts of the retrieved cups. A comparison of the two models then showed the total volume of the polyethylene debris. The optical scanning method was validated against the gravimetric method using three new acetabular cups that were worn out on a hip pendulum simulator. Validation shows that the optical scanning method is a valid method for wear analysis of the retrieved UHMWPE acetabular cups.

Total hip replacement, polyethylene, wear measurement, optical digitalization, volumetric wear

Total hip replacement, polyethylene, wear measurement, optical digitalization, volumetric wear

RANUŠA, M.; GALLO, J.; VRBKA, M.; HOBZA, M.; PALOUŠEK, D.; KŘUPKA, I.; HARTL, M.

2019

01.06.2018

Society of Tribologist and Lubrication Engineers

1545-858X

TRIBOLOGY & LUBRICATION TECHNOLOGY

74

6

United States of America

68

84

12

https://www.proquest.com/docview/2042173814?accountid=17115

http://hdl.handle.net/