Authors: Manish Paliwal, D. Gordon Allan, Peter Filip
Addresses: Department of Mechanical Engineering, The College of New Jersey, Ewing, NJ 08618, USA. ' Division of Orthopaedic Surgery, Southern Illinois University School of Medicine, Springfield, IL 62794, USA. ' Center for Advanced Friction Studies, Southern Illinois University at Carbondale, Carbondale, IL 62901, USA
Abstract: This paper reports the analysis of a modular S-ROM hip implant, which was retrieved at revision, secondary to aseptic loosening approximately after 24-months of implantation. Microscopic analysis confirmed the presence of pitting, fretting corrosion, plastic deformation, and stress induced corrosion cracking. Energy-dispersive x-ray microanalysis of the stem surface revealed the release of metal ions. High resolution inductively coupled plasma mass spectroscopy confirmed elevated titanium ion levels (4.66 ppb) in blood serum. Finite element analysis of the implant showed that the micromotion and stress levels were the maximum at the proximal-lateral region of the taper junction, in congruence with the observation.
Keywords: retrieval analysis; cementless total hip arthroplasty; modular total hip arthroplasty; microscopy; hip implants; implant retrieval; pitting; fretting corrosion; plastic deformation; stress; corrosion cracking; titanium ion levels; blood serum; finite element analysis; FEA; micromotion.
International Journal of Functional Informatics and Personalised Medicine, 2009 Vol.2 No.1, pp.45 - 56
Available online: 27 Jan 2009 *Full-text access for editors Access for subscribers Purchase this article Comment on this article