title: In vivo comparison of wear particles between highly crosslinked polyethylene and conventional polyethylene in the same design of total knee arthroplasties.
abstract: Reduction of wear with highly crosslinked polyethylene (HXLPE) has been reported in in vitro and in vivo studies of total hip prostheses. However, use of HXLPE in total knee prostheses is still controversial. The aim of this study was to compare in vivo polyethylene wear particle generation of HXLPE with that of conventional polyethylene in total knee prostheses of the same design. Synovial fluid was obtained from four knees with HXLPE inserts and three knees with conventional polyethylene inserts at 1 year after operation. Polyethylene particles were isolated and examined using a scanning electron microscope and image analyzer. The total number of particles in each knee was 0.28 +/- 0.12 x 10(6) in HXPLE group (mean +/- standard error) and 6.87 +/- 2.85 x 10(6) in conventional polyethylene group (p = 0.040). Particle size (equivalent circle diameter) was 0.64 +/- 0.07 microm in HXPLE group and 1.21 +/- 0.21 microm in conventional polyethylene group (p = 0.030). Particle shape (aspect ratio) was 1.33 +/- 0.10 in HXLPE and 1.88 +/- 0.19 in conventional polyethylene (p = 0.035). Thepercentage of particles of submicron size was greater than 90% in HXLPE group and 55% in conventional polyethylene group. Except for the material of the polyethylene insert, the design and material of prostheses were completely the same in both groups. The HXLPE insert generated fewer, smaller, and rounder polyethylene wear particles than the conventional polyethylene insert in the early stage after surgery.
authors.affiliation: Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, Abeno-ku, Osaka 545-8585, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Iwakiri
authors.affiliation: Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, Abeno-ku, Osaka 545-8585, Japan.
authors.forename: Yukihide
authors.initials: Y
authors.lastname: Minoda
authors.affiliation: Department of Orthopaedic Surgery, Osaka General Medical Center, Sumiyoshi-ku, Osaka 558-8558, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Kobayashi
authors.affiliation: Department of Orthopaedic Surgery, Osaka General Medical Center, Sumiyoshi-ku, Osaka 558-8558, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Sugama
authors.affiliation: Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, Abeno-ku, Osaka 545-8585, Japan.
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Iwaki
authors.affiliation: Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, Abeno-ku, Osaka 545-8585, Japan.
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Inori
authors.affiliation: Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, Abeno-ku, Osaka 545-8585, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Hashimoto
authors.affiliation: Department of Orthopaedic Surgery, Osaka Saiseikai Nakatsu Hospital, Kita-ku, Osaka 530-0012, Japan.
authors.forename: Hirotsugu
authors.initials: H
authors.lastname: Ohashi
authors.affiliation: Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, Abeno-ku, Osaka 545-8585, Japan.
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Ohta
authors.affiliation: Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, Abeno-ku, Osaka 545-8585, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Fukunaga
authors.affiliation: Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, Abeno-ku, Osaka 545-8585, Japan.
authors.forename: Kunio
authors.initials: K
authors.lastname: Takaoka
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee; D001672:Biocompatible Materials; D003432:Cross-Linking Reagents; D005260:Female; D006801:Humans; D007720:Knee Prosthesis; D008297:Male; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D010316:Particle Size; D011095:Polyethylenes / Q000737:chemistry*; D013582:Synovial Fluid / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D003432:Cross-Linking Reagents; D011095:Polyethylenes