Quantitative analysis of UHMWPE wear debris isolated from the periprosthetic femoral tissues from a series of Charnley total hip arthroplasties

Article type: Research Article

Authors: Bell, J. | Tipper, J.L. | Ingham, E. | Stone, M.H. | Wroblewski, B.M. | Fisher, J.^;

Affiliations: Medical and Biological Engineering (MBE), School of Mechanical Engineering, University of Leeds, Leeds, LS2 9JT, UK | School of Biochemistry and Molecular Biology, Division of Microbiology, University of Leeds, Leeds, LS2 9JT, UK | Department of Orthopaedic Surgery, Leeds General Infirmary, Leeds, LS1 3EX, UK | Centre for Hip Surgery, Wrightington Hospital for Joint Disease, Appley Bridge, Wigan, WN6 9EP, UK | School of Mechanical Engineering, University of Leeds, Leeds, LS2 9JT, UK

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Abstract: Submicrometer and micrometer‐sized UHMWPE wear particles have been associated with osteolysis and failure of total hip replacements. A previous study by Tipper et al. [16] examined the wear debris isolated from the acetabular periprosthetic tissues from 18 Charnley total hip replacements, and compared this data to the tribological variables of the prostheses. The present study aimed to isolate the UHMWPE wear debris from the femoral periprosthetic tissues from 10 of the same cohort of patients, and compare it with the debris isolated from the corresponding acetabular tissues. A variety of particle morphologies were observed, discrete submicrometer particles, along with flakes and fibrils. The particle size distributions ranged from 0.1 to >250 μm, however, the largest particles were only found in samples when the femoral head damage was characterised as low (Rpm<0.2 μm). The mode of the frequency distribution of particles was in the range of 0.1–0.5 μm for all the femoral tissues. Considerable variations were found in the mass distributions of the wear particles as a function of size for different patients. The net mass of debris isolated from the femoral tissues was significantly lower (p<0.05, Student's t‐test) than from the corresponding acetabular tissues. This along with considerable spatial variation in the net mass of debris isolated from the different regions of the same sample of acetabular tissue, indicates that the transportation of the debris has a marked effect on the net mass of debris accumulated in different tissues.

Keywords: UHMWPE, wear, wear debris, explants, total hip arthroplasty

Journal: Bio-Medical Materials and Engineering, vol. 12, no. 2, pp. 189-201, 2002