title: Characteristics of Hylamer polyethylene particles isolated from peri-prosthetic tissues of failed cemented total hip arthroplasties.
abstract: Polyethylene wear particles are one of the most important factors affecting the results of total hip arthroplasty. Hylamer, a highly crystalized ultra-high-molecular-weight polyethylene, has been used in total hip arthroplasty for wear reduction, but has exhibited high wear rate and excessive osteolysis. The aim of the present study was to examine Hylamer wear particles in peri-prosthetic tissues with osteolysis obtained from two cases of failed cemented total hip arthroplasty at 8 and 6 years after operation. Polyethylene particles were isolated, and examined using a scanning electron microscope and image analyzer. Total numbers of Hylamer polyethylene particles in the two cases were 5.6 x 10(9) and 8.0 x 10(9) g(-1). Particle sizes (in equivalent circle diameter) for the two cases were 1.07 +/- 0.06 microm and 1.16 +/- 0.05 microm, and particle shapes (roundness) were 3.05 +/- 0.22 and 3.76 +/- 0.28. The Hylamer polyethylene particles were larger in size and more elongated and their number was larger, compared with the corresponding reported values for particles generated from conventional polyethylene. This increase in particle number and elongation may lead to early osteolysis in total hip arthroplasty with Hylamer.
authors.affiliation: Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi Abeno-ku, Osaka 545-8585, Japan. kentucky@msic.med.osaka-cu.ac.jp
authors.forename: Kentaro
authors.initials: K
authors.lastname: Iwakiri
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Iwaki
authors.forename: Akio
authors.initials: A
authors.lastname: Kobayashi
authors.forename: Yukihide
authors.initials: Y
authors.lastname: Minoda
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kagiyama
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Kadoya
authors.forename: Kunio
authors.initials: K
authors.lastname: Takaoka
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip; D001672:Biocompatible Materials / Q000737:chemistry / Q000378:metabolism; D002484:Cementation; D019544:Equipment Failure Analysis; D005260:Female; D006622:Hip Prosthesis; D006801:Humans; D010316:Particle Size; D011095:Polyethylenes / Q000737:chemistry / Q000378:metabolism; D011475:Prosthesis Failure; D012086:Reoperation