title: Comparison of the Genesis II total knee replacement with oxidised zirconium and cobalt-chromium femoral components in the same patients: a prospective, double-blind, randomised controlled study.
abstract: Despite many claims of good wear properties following   total knee replacement (TKR) with an oxidised zirconium (OxZr) femoral   component, there are conflicting clinical results. We hypothesised   that there would be no difference in either the mid-term clinical   and radiological outcomes or the characteristics of the polyethylene   wear particles (weight, size and shape) in patients using an OxZr   or cobalt-chrome (CoCr) femoral component. In all 331 patients underwent   bilateral TKR, receiving an OxZr femoral component in one knee and   a CoCr femoral component in the other. The mean follow-up was 7.5   years (6 to 8). Following aspiration, polyethylene wear particles   were analysed using thermogravimetric methods and scanning electron   microscopy. At the most recent follow-up, the mean Knee Society   score, Western Ontario and McMaster Universities Osteoarthritis   Index score, range of movement and satisfaction score were not significantly   different in the two groups. The mean weight, size, aspect ratio   and roundness of the aspirated wear particles were similar for each   femoral component. Survivorship of the femoral, tibial and patellar   components was 100% in both groups. In the absence of evidence of an advantage in the medium term   we cannot justify the additional expense of an OxZr femoral component.
authors.affiliation: Ewha Womans University School of Medicine, The Joint Replacement Center, 911-1, Mokdong, YangChun-Gu, Seoul 158710, South Korea. younghookim@ewha.ac.kr
authors.forename: Y-H
authors.initials: YH
authors.lastname: Kim
authors.forename: J-W
authors.initials: JW
authors.lastname: Park
authors.forename: J-S
authors.initials: JS
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000534:rehabilitation; D002858:Chromium Alloys; D004311:Double-Blind Method; D004434:Early Ambulation; D019544:Equipment Failure Analysis; D005260:Female; D005269:Femur; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000503:physiopathology; D007720:Knee Prosthesis; D008297:Male; D008422:Materials Testing; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging / Q000628:therapy*; D017060:Patient Satisfaction / Q000706:statistics & numerical data*; D020959:Polyethylene / Q000032:analysis; D011446:Prospective Studies; D011474:Prosthesis Design; D011859:Radiography; D016059:Range of Motion, Articular; D013582:Synovial Fluid / Q000737:chemistry / Q000166:cytology; D015040:Zirconium
chemical_list: D002858:Chromium Alloys; D020959:Polyethylene; D015040:Zirconium