In Vivo Corrosion of Modular Dual-Mobility Implants: A Retrieval Study.
J Arthroplasty
; 35(11): 3326-3329, 2020 11.
Article
em En
| MEDLINE
| ID: mdl-32600814
ABSTRACT
BACKGROUND:
Modular dual-mobility (MDM) total hip arthroplasty (THA) implants have an additional metal-metal interface between the metal liner and outer metal shell that poses a risk of corrosion. The purpose of this study is to evaluate retrieved MDM liners to evaluate qualitative and quantitative damage and corrosion patterns at this interface.METHODS:
Twelve MDM implants of one design with a mean in situ duration of 26 months (range, 1-57 months) were evaluated. Six implants (50%) were from primary THAs and 6 (50%) from revision THAs. The taper region of the liner at risk of damage was qualitatively graded using modified Goldberg criteria while quantitative dimensional assessment was performed with a validated coordinate measurement machine.RESULTS:
Among the retrieved implants, 2 (17%) demonstrated severe grade 4 corrosion, 5 (42%) moderate grade 3 corrosion, 4 (33%) mild grade 2 corrosion, and 1 (8%) grade 1 (no visible corrosion). Mean maximum linear corrosion depth at the taper interface measured 35.5 microns (range, 8.4-176.2 microns). All implants had a maximum linear corrosion depth >7 microns, a threshold suggestive of potentially clinically significant material loss. Three corrosion patterns were identified generalized corrosion, a stripe of corrosion about the middle of the taper region, and focal areas of corrosion at the portion of the taper closest to the joint surface.CONCLUSION:
Visual and dimensional analysis of all 12 retrieved MDM implants demonstrated identifiable corrosion/wear of the cobalt-chromium metal liner taper of varying severity. These implants should be used judiciously until larger series with clinical correlation can be completed.Palavras-chave
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Base de dados:
MEDLINE
Assunto principal:
Artroplastia de Quadril
/
Prótese de Quadril
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article