Effects of specimen variables and stress amplitude on the S-N analysis of two PMMA based bone cements

Sheafi, E.M. and Tanner, K.E. (2017) Effects of specimen variables and stress amplitude on the S-N analysis of two PMMA based bone cements. International Journal of Fatigue, 105, pp. 119-127. (doi: 10.1016/j.ijfatigue.2017.08.019)

Abstract

The fatigue performance of bone cement is influenced by the testing parameters. In previous in vitro fatigue studies, different testing conditions have been used leading to inconsistencies in the findings between the studies, and consequent uncertainties about the effects of testing specimen specifications and stress parameters. This study evaluates the role of specimen variables (namely; specimen cross-section shape, surface production method and cement composition) in a range of in vitro stress amplitudes (±12.5, ±15, ±20, ±30 MPa), using S-N (Wöhler) analysis. The two main findings are: while specimen cross-section configuration and fabrication method (specimen type) played a key role in controlling the fatigue longevity of the same cement, the stress amplitude was seen as the dominant controlling variable to affect the fatigue behaviour of different cements when using the same specimen type. Thus, considering the effect of specimen type, testing at high stress amplitudes should be treated with caution, particularly in tension-compression loading, to ensure fatigue failure occurs due to mechanical rather than thermal effects and thus models the in vivo behaviour.

• Item Type: Articles
• Additional Information: The Libyan Government is thanked for funding the research (PhD studentship ref 6978).
• Keywords: Polymethylmethacrylate, bone cement, stress amplitude, S-N curve, DSC analysis.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Tanner, Professor Kathleen and Sheafi, Mr Emadeddin
• Authors: Sheafi, E.M., and Tanner, K.E.
• Subjects: T Technology > T Technology (General)
• College/School: College of Science and Engineering > School of Engineering > Biomedical Engineering
• Research Group: Biomaterials
• Journal Name: International Journal of Fatigue
• Publisher: Elsevier
• ISSN: 0142-1123
• ISSN (Online): 1879-3452
• Published Online: 24 August 2017
• Copyright Holders: Copyright © 2017 Elsevier Ltd.
• First Published: First published in International Journal of Fatigue 105:119-127
• Publisher Policy: Reproduced in accordance with the publisher copyright policy