title: MRI findings following metal on metal hip arthroplasty and their relationship with metal ion levels and acetabular inclination angles.
abstract: Following the global recall of all ASR metal on metal hip products, our aim was to correlate MRI findings with acetabular inclination angles and metal ion levels in patients with these implants. Both cobalt and chromium levels were significantly higher in the presence of a periprosthetic fluid collection. There was no association between the presence of a periprosthetic mass, bone marrow oedema, trochanteric bursitis or greater levels of abductor muscle destruction for cobalt or chromium. There was no association between the level of periprosthetic tissue reaction and the acetabular inclination angle with any of the pathologies identified on MRI. The relationship between MRI pathology, metal ion levels and acetabular inclination angles in patients with ASR implants remains unclear adding to the complexity of managing patients.
authors.affiliation: Lourdes Orthopaedic Hospital, Kilcreene, Kilkenny, Ireland.
authors.forename: Ciara M
authors.initials: CM
authors.lastname: Fox
authors.affiliation: Lourdes Orthopaedic Hospital, Kilcreene, Kilkenny, Ireland.
authors.forename: Karen M
authors.initials: KM
authors.lastname: Bergin
authors.affiliation: School of Mathematical Sciences, University College Dublin, Belfield, Dublin 4, Ireland.
authors.forename: Gabrielle E
authors.initials: GE
authors.lastname: Kelly
authors.affiliation: Lourdes Orthopaedic Hospital, Kilcreene, Kilkenny, Ireland.
authors.forename: Gerry F
authors.initials: GF
authors.lastname: McCoy
authors.affiliation: Department of Radiology, Waterford Regional Hospital, Waterford, Ireland.
authors.forename: Anthony G
authors.initials: AG
authors.lastname: Ryan
authors.affiliation: Lourdes Orthopaedic Hospital, Kilcreene, Kilkenny, Ireland.
authors.forename: John F
authors.initials: JF
authors.lastname: Quinlan
mesh_terms: D000077:Acetabulum / Q000473:pathology* / Q000601:surgery*; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects*; D002062:Bursitis / Q000209:etiology / Q000473:pathology; D002857:Chromium / Q000097:blood; D003035:Cobalt / Q000097:blood; D016208:Databases, Factual; D004487:Edema / Q000209:etiology / Q000473:pathology; D006615:Hip / Q000601:surgery; D006621:Hip Joint / Q000473:pathology / Q000601:surgery; D006622:Hip Prosthesis; D006801:Humans; D007477:Ions / Q000097:blood; D008279:Magnetic Resonance Imaging; D057052:Medical Device Recalls; D061825:Metal-on-Metal Joint Prostheses / Q000009:adverse effects*; D011474:Prosthesis Design
chemical_list: D007477:Ions; D002857:Chromium; D003035:Cobalt
keywords: ARMD; MARS MRI; inclincation; metal ions; metal-on-metal arthroplasty