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PubMed · 7235879

Fracture hip prostheses due to welding defects.

R Kousbroek·P Ducheyne·G Van der Perre·E Aernoudt·J C Mulier
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Abstract

Two retrieved Moore type hip prostheses of cast Co-Cr-Mo-alloy were examined after metallic failure. The first case concerns a fatigue fracture in the stem of the prosthesis due to an abrupt change in the cross-sectional area and the presence of inappropriate welding beads in the stem. The abrupt change occurring at a transition from an I-beam into a rectangular profile gives rise to stress concentrations thus increasing change of fatigue crack initiation. The second case is a fracture of the hollow head of the prosthesis through a weld. The two parts of the cast femoral head were incompletely welded. Comparison with similar welds in other femoral heads of prostheses of the same type reveals a poor welding uniformity. Hence, both fractures are associated with the welding process. A critical investigation is needed to find optimal welding conditions for Co-Cr-Mo-alloy prostheses.

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Biomechanical PhenomenaFemaleHip ProsthesisHumansMiddle AgedPostoperative ComplicationsProsthesis DesignWeldingJournal Article

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BibTeXRIS

R Kousbroek, P Ducheyne, G Van der Perre, E Aernoudt, J C Mulier. 1981. Fracture hip prostheses due to welding defects.. https://doi.org/10.1007/bf00389711

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