title: Elevated serum concentrations of cobalt, chromium, nickel, and manganese after metal-on-metal alloarthroplasty of the hip: a prospective randomized study.
abstract: In this prospective randomized study, we investigate metal ion concentrations and clinical outcome 2 years after metal-on-metal (28 patients) or metal-on-polyethylene (26 patients) hip arthroplasty with 28-mm modular heads. Metal ion concentrations in patient serum were analyzed by high-resolution plasma mass spectrometry. The clinical outcome was almost identical in both groups with respect to the Harris hip score and the Medical Outcome Study Short Form-36; and on plain radiography, no signs of loosening occurred in any group. In the metal-on-metal group, concentrations of all investigated ions increased significantly when compared with preoperative values: cobalt, 15.3-fold (95% confidence interval [CI], 9.4-21.2); chromium, 5.2-fold (CI, 3.5-7.0); nickel, 2.1-fold (CI, 1.2-3.0); and manganese, 1.6-fold (CI, 1.3-2.0). In the metal-on-polyethylene group, a smaller but significant increase in the concentrations of cobalt and nickel occurred, whereas concentrations of the other ions did not change significantly.
authors.affiliation: Department of Molecular Medicine and Surgery, Section of Orthopaedics, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Henrik
authors.initials: H
authors.lastname: Dahlstrand
authors.forename: André
authors.initials: A
authors.lastname: Stark
authors.forename: Lucas
authors.initials: L
authors.lastname: Anissian
authors.forename: Nils P
authors.initials: NP
authors.lastname: Hailer
mesh_terms: D000328:Adult; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000295:instrumentation* / Q000379:methods; D002857:Chromium / Q000097:blood*; D003035:Cobalt / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006621:Hip Joint / Q000000981:diagnostic imaging / Q000502:physiology / Q000601:surgery; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008345:Manganese / Q000097:blood*; D008875:Middle Aged; D009532:Nickel / Q000097:blood*; D010003:Osteoarthritis / Q000601:surgery; D020959:Polyethylene; D011446:Prospective Studies; D011475:Prosthesis Failure; D011788:Quality of Life; D011859:Radiography; D016896:Treatment Outcome
chemical_list: D002857:Chromium; D003035:Cobalt; D008345:Manganese; D009532:Nickel; D020959:Polyethylene