Premium
Failure analysis of two Ti‐alloy total hip arthroplasty femoral stems fractured in vivo
Author(s) -
Magnissalis E. A.,
Zinelis S.,
Karachalios Th.,
Hartofilakidis G.
Publication year - 2003
Publication title -
journal of biomedical materials research part b: applied biomaterials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.665
H-Index - 108
eISSN - 1552-4981
pISSN - 1552-4973
DOI - 10.1002/jbm.b.10003
Subject(s) - ultimate tensile strength , alloy , microstructure , materials science , titanium alloy , fracture (geology) , femoral fracture , tensile testing , composite material , medicine , surgery , femur
Failure of total hip arthroplasty femoral stems is a serious clinical complication. Even modern metal alloys and designs sometimes suffer such incidents. The reported study aimed at the investigation of the reasons leading the in vivo fracture of two Ti6Al4V femoral stems. Stems were retrieved during revision surgery approximately 2 years postoperatively. Examination and analysis included XRF spectrometry for identification of chemical composition, macroscopic examination and topographical measurements, SEM study of fracture surfaces, study of alloy microstructure by optical microscopy, and finally measurement of mechanical properties by means of tensile testing conducted on alloy samples machined from the stems themselves. Macroscopic examination and measurements showed close topographical similarity between the two fractures. XRF spectrometry, tensile testing, and microstructure analysis identified the alloy as a typical Ti6Al4V surgical titanium alloy. During SEM analysis the fracture surfaces exhibited characteristic fatigue striations tidally running on the cross sections, which were considered as the weakest ones regarding toward geometry and stress concentration. Fracture in both stems occurred due to fatigue along these cross sections. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 299–305, 2003