title: High performance of metal-on-metal bearings: a case report.
abstract: There has been considerable initial success with the use of total hip and resurfacing metal-metal implants tempered by poor performance of certain bearing designs, specifically small and/or abnormal component orientation. With a growing number of reports relating to adverse local tissue reactions, the need to monitor ion levels is crucial. This report presents a case of an extremely active bilateral metal-metal implant patient who had severe arthritis of the left hip and was originally treated with a cementless metal-on-polyethylene surface replacement. This implant lasted 12~years and after complete wear through of the polyethylene, the prosthesis was converted to metal-on-metal total hip. The patient continued to cycle vigorously and engaged in downhill skiing. Eventually his contralateral hip developed arthritis and he underwent metal-on-metal surface arthroplasty. Since his last surgery 8~years ago, the patient has resumed his activities, cycling an average of 6,400 miles and skiing over 60~days a year. He has been followed clinically and radiographically for 23 years with ion levels measured serially.
authors.affiliation: St. Vincent Medical Center, Los Angeles, CA, USA.
authors.forename: Regina P
authors.initials: RP
authors.lastname: Woon
authors.forename: Harlan C
authors.initials: HC
authors.lastname: Amstutz
mesh_terms: D019644:Arthroplasty, Replacement, Hip / Q000295:instrumentation*; D001642:Bicycling / Q000293:injuries / Q000706:statistics & numerical data*; D002857:Chromium / Q000097:blood; D003035:Cobalt / Q000097:blood; D006801:Humans; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000601:surgery*; D011474:Prosthesis Design; D012086:Reoperation; D012865:Skiing / Q000706:statistics & numerical data*
chemical_list: D002857:Chromium; D003035:Cobalt