Chuter, G. S. J. and Cloke, D. J. and Mahomed, A. and Partington, P. F. and Green, S. M. (2007) Wear analysis of failed acetabular polyethylene:a comparison of analytical methods. Journal of Bone and Joint Surgery, 89B (2). pp. 273-279. ISSN 0301-620XFull text not available from this repository.
There are many methods for analysing wear volume in failed polyethylene acetabular components. We compared a radiological technique with three recognised ex vivo methods of measurement. We tested 18 ultra-high-molecular-weight polyethylene acetabular components revised for wear and aseptic loosening, of which 13 had pre-revision radiographs, from which the wear volume was calculated based upon the linear wear. We used a shadowgraph technique on silicone casts of all of the retrievals and a coordinate measuring method on the components directly. For these techniques, the wear vector was calculated for each component and the wear volume extrapolated using mathematical equations. The volumetric wear was also measured directly using a fluid-displacement method. The results of each technique were compared. The series had high wear volumes (mean 1385 mm(3); 730 to 1850) and high wear rates (mean 205 mm(3)/year; 92 to 363). There were wide variations in the measurements of wear volume between the radiological and the other techniques. Radiograph-derived wear volume correlated poorly with that of the fluid-displacement method, co-ordinate measuring method and shadowgraph methods, becoming less accurate as the wear increased. The mean overestimation in radiological wear volume was 47.7% of the fluid-displacement method wear volume. Fluid-displacement method, coordinate measuring method and shadowgraph determinations of wear volume were all better than that of the radiograph-derived linear measurements since they took into account the direction of wear. However, only radiological techniques can be used in vivo and remain useful for monitoring linear wear in the clinical setting. Interpretation of radiological measurements of acetabular wear must be done judiciously in the clinical setting. In vitro laboratory techniques, in particular the fluid-displacement method, remain the most accurate and reliable methods of assessing the wear of acetabular polyethylene.
|Journal or Publication Title:||Journal of Bone and Joint Surgery|
|Subjects:||T Technology > TA Engineering (General). Civil engineering (General)|
|Departments:||Faculty of Science and Technology > Engineering|
|Deposited On:||17 Oct 2012 10:24|
|Last Modified:||10 Apr 2014 00:05|
Actions (login required)