title: Radiographically undetectable periprosthetic osteolysis with ASR implants: the implication of blood metal ions.
abstract: Patients with ASR implants (resurfacing and large-diameter (XL) metal-on-metal (MoM) total hip arthroplasty), even if asymptomatic and with a stable prosthesis, may present extremely high blood metal ion levels. We report on a consecutive series of fourteen ASR revisions, focusing on osteolysis and their radiographic correspondence and their correlation with blood metal ion levels. At revision, seven hips revealed severe periacetabular osteolysis which was radiographically undetectable in six and asymptomatic in five. Seven hips with no acetabular osteolysis had significantly lower serum Cr and Co ion concentrations (respectively 25.2, 41.1 μg/l) compared to the seven hips with severe acetabular bone loss (respectively 70.1, 147.0 μg/l). Elevated blood metal ion levels should be considered as a warning of undetectable and ongoing periprosthetic osteolysis in asymptomatic patients with ASR prosthesis.
authors.affiliation: 5th Orthopaedic Department (Department of Hip Surgery), Policlinico San Donato, Milan, Italy.
authors.forename: Filippo
authors.initials: F
authors.lastname: Randelli
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Banci
authors.forename: Sara
authors.initials: S
authors.lastname: Favilla
authors.forename: Daniela
authors.initials: D
authors.lastname: Maglione
authors.forename: Alberto
authors.initials: A
authors.lastname: Aliprandi
mesh_terms: D000077:Acetabulum / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D000328:Adult; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000295:instrumentation; D002857:Chromium / Q000097:blood*; D003035:Cobalt / Q000097:blood*; D005260:Female; D006621:Hip Joint / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D006622:Hip Prosthesis / Q000009:adverse effects* / Q000145:classification*; D006801:Humans; D015994:Incidence; D007477:Ions / Q000097:blood; D008297:Male; D008875:Middle Aged; D010014:Osteolysis / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000473:pathology*; D011474:Prosthesis Design; D011859:Radiography; D012086:Reoperation; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D007477:Ions; D002857:Chromium; D003035:Cobalt
keywords: ASR; acetabular osteolysis; blood metal ions; metal-on-metal