title: Migration of metal-on-metal versus ceramic-on-polyethylene hip prostheses.
abstract: In a prospective randomized study, 32 metal-on-metal prostheses and 29 ceramic-on-polyethylene prostheses of similar design were implanted in 59 patients. Radiolucency, cup migration, wear, and function were examined after a minimum of 2 years followup (followup rate, 87%). The purpose of the current study was to evaluate whether higher frictional torque of metal-on-metal will lead to a higher rate of early metal-on-metal cup loosening. A computer-assisted method was used for wear and migration measurements of the acetabular component. Metal-on-metal prostheses migrated in a craniocaudad direction significantly less than ceramic-on-polyethylene prostheses. The mean total migration for both types of prostheses exceeded 1.5 mm at 2 years. Clinically, no difference between the two prostheses regarding activity, pain, or range of motion was found at 2 years. As migration of metal-on-metal prostheses was not higher in comparison with ceramic-on-polyethylene prostheses, the expected higher frictional torque of metal-on-metal prostheses did not increase migration during short-term followup. The different debris produced by both bearings did not influence the short-term results of this study, but might cause different long-term results.
authors.affiliation: Department of Orthopedics, University of Innsbruck, Austria.
authors.forename: C
authors.initials: C
authors.lastname: Pabinger
authors.forename: R
authors.initials: R
authors.lastname: Biedermann
authors.forename: B
authors.initials: B
authors.lastname: Stöckl
authors.forename: M
authors.initials: M
authors.lastname: Fischer
authors.forename: M
authors.initials: M
authors.lastname: Krismer
mesh_terms: D000368:Aged; D002516:Ceramics; D019544:Equipment Failure Analysis / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006621:Hip Joint / Q000000981:diagnostic imaging; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008670:Metals; D008875:Middle Aged; D020959:Polyethylene; D011446:Prospective Studies; D011474:Prosthesis Design; D011475:Prosthesis Failure; D011859:Radiography; D016059:Range of Motion, Articular
chemical_list: D008670:Metals; D020959:Polyethylene