Failure mechanisms in CoCrMo modular femoral stems for revision total hip arthroplasty.
In this retrieval study, we reported the failure mechanisms of the CoCrMo-based hip implants. Systematic analyses on the clinically failed modular femoral stems from Revitan™ revision prostheses revealed a multistep fracture process. Multiple microcracks were first developed under the combined action of pitting corrosion and dynamic tensile stress on the lateral side of the CoCrMo connection taper. These microcracks then served as the initiation sites of further corrosion fatigue cracking leading to the final catastrophic failure. This crack initiation process has not been previously reported on retrieved CoCrMo components and our findings provide valuable information on the clinical performance of such implants, as well as the material selection and structural designs of future modular stems. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1525-1535, 2017.
Department of Materials Engineering, University of British Columbia, Vancouver, BC, Canada.|Centre for Hip Health and Mobility, University of British Columbia, Vancouver, BC, Canada.
Qiong
Q
Wang
Department of Orthopedics, University of British Columbia, Vancouver, BC, Canada.|Consultant Orthopedic Surgeon, Royal Orthopedic Hospital, Birmingham, UK.
Michael
M
Parry
Department of Orthopedics, University of British Columbia, Vancouver, BC, Canada.
Bassam A
BA
Masri
Department of Orthopedics, University of British Columbia, Vancouver, BC, Canada.
Clive
C
Duncan
Department of Materials Engineering, University of British Columbia, Vancouver, BC, Canada.|Centre for Hip Health and Mobility, University of British Columbia, Vancouver, BC, Canada.
Rizhi
R
Wang
D000368:Aged; D000497:Alloys; D019644:Arthroplasty, Replacement, Hip; D002857:Chromium; D003035:Cobalt; D019544:Equipment Failure Analysis; D005260:Female; D006622:Hip Prosthesis / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008982:Molybdenum; D011475:Prosthesis Failure / Q000009:adverse effects*
D000497:Alloys; D002857:Chromium; D003035:Cobalt; D008982:Molybdenum
CoCrMo alloy; corrosion fatigue; crevice corrosion; modular hip implant; pitting