The sensitivity of cobalt (Co) and chromium (Cr) ion-levels in detecting poorly performing metal-on-metal hip implants is low. This study proposes that serial changes in ion-levels are a more accurate marker of arthroplasties at risk.
Serial metal ion-levels and implant data of 285 patients with ASR resurfacing or replacement were studied. Patient and implant characteristics were analysed using univariate and multivariate analyses.
111 (39%) had revision surgery. Time since index surgery (p<0.001), acetabular inclination (p<0.001), their interaction (p<0.001) and femoral head size (p = 0.01) were significant variables. Head size (≤51 mm) had lower Co and Cr levels (p = 0.01). Cr/Co showed marginal decrease over time in the unrevised group and no decrease prerevision.
Repeated measurement of ion-levels were higher in the revision group suggesting that serial measurements rather than absolute values may have a role to play in predicting implant failure.
Hip Int 2017; 27(1): 14 - 20
Article Type: ORIGINAL RESEARCH ARTICLE
AuthorsGavin McHugh, Rajiv Merchant, Gabrielle E. Kelly, Karen M. Bergin, Gerald F. McCoy, Andrew P. Wozniak, John F. Quinlan
- • Accepted on 17/06/2016
- • Available online on 20/01/2017
- • Published in print on 21/02/2017
This article is available as full text PDF.
- McHugh, Gavin [PubMed] [Google Scholar] 1
- Merchant, Rajiv [PubMed] [Google Scholar] 1, * Corresponding Author (firstname.lastname@example.org)
- Kelly, Gabrielle E. [PubMed] [Google Scholar] 2
- Bergin, Karen M. [PubMed] [Google Scholar] 1
- McCoy, Gerald F. [PubMed] [Google Scholar] 1
- Wozniak, Andrew P. [PubMed] [Google Scholar] 1
- Quinlan, John F. [PubMed] [Google Scholar] 1
Lourdes Orthopaedic Hospital, Kilcreene, Kilkenny - Ireland
School of Mathematical Sciences, University College Dublin, Dublin - Ireland