QUT ePrints

Biomechanics of osteoporotic crush fractures using synthetic vertebrae

McDonald, Katrina A., Adam, Clayton J., & Pearcy, Mark J. (2005) Biomechanics of osteoporotic crush fractures using synthetic vertebrae. In Raghunath, Michael & Toh, Siew Lok (Eds.) The Proceeding of 12th International Conference on Biomedical Engineering, 7-10 December 2005, Suntec Singapore International Convention and Exhibition Centre, Singapore.

Abstract

An estimated 30-50% of women and 20-30% of men will develop vertebral fractures in their lifetime, 85% of which are associated with osteoporosis. Bone loss in osteoporosis leads to reduced stiffness and strength of vertebral cancellous bone, and eventual loss of cortical wall thickness. This study developed synthetic vertebra models for investigation of vertebrae mechanics in osteoporosis - specifically the effects of bone density and micro-architecture on vertebral body strength and stiffness. Rapid prototyping techniques were used to create models with dimensions based on human lumbar vertebrae. A three dimensional matrix of longitudinal and transverse struts was used to simulate trabecular bone. Matrix dimensions were varied to represent differing degrees of osteoporosis. Cortical wall thickness was also reduced to simulate serverely osteoporotic vertebrae. Foam and silicone mouldings were used as intervertebral disk phantoms. The synthetic vertebrae were tested in uniaxial compression at constant strain rate (5mm/min). Force and displacement were logged until specimen failure and video was used to record gross vertebral fracture patterns. Reduction in trabecular bone volume fraction from 19% to 10% resulted in 65% decrease in strength and 70% decrease in stiffness, while a 25% reduction in cortical wall thickness reduced the strength of the vertebrae by 58%. The large decreases in vertebral stiffness and strength with bone loss are comparable to those found in previous studies. Reducing cortical wall thickness did not affect vertebral stiffness greatly, but this was most likely due to limitations in the dimensional accuracy of the rapid prototyping technology. Overall, the synthetic vertebra models provide a repeatable and biomechanically useful tool for the study of vertebral compression fracture mechanics.

Impact and interest:

Citation countsare sourced monthly from Scopus and Web of Science® citation databases.

These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.

Citations counts from the Google Scholar™ indexing service can be viewed at the linked Google Scholar™ search.

Full-text downloads:

68 since deposited on 05 Feb 2009
7 in the past twelve months

Full-text downloadsdisplays the total number of times this work’s files (e.g., a PDF) have been downloaded from QUT ePrints as well as the number of downloads in the previous 365 days. The count includes downloads for all files if a work has more than one.

ID Code: 17304
Item Type: Conference Paper
Keywords: osteoporosis, synthetic vertebra, cancellous density, micro-architecture, fracture mechanism, vertebral stiffness, cortical wall stiffness
ISBN: 981054572X
ISSN: 1727-1983
Divisions: Past > QUT Faculties & Divisions > Faculty of Built Environment and Engineering
Current > Institutes > Institute of Health and Biomedical Innovation
Past > Schools > School of Engineering Systems
Copyright Owner: Copyright 2005 [please consult the author]
Copyright Statement: Authors retain all proprietary rights in any process, procedure, or article of manufacture described in the work.
Deposited On: 06 Feb 2009 09:04
Last Modified: 09 Jun 2010 23:18

Export: EndNote | Dublin Core | BibTeX

Repository Staff Only: item control page