μ-Finite Element Analysis of Human Bone Structures
Prof. Dr. P. Arbenz,
ETH Zurich, Institute of Computational Science
Prof. Dr. G. H. van Lenthe,
KU Leuven, Department of Mechanical Engineering
Prof. Dr. R. Müller,
ETH Zurich, Institute of Biomechanics
Dr. M. Sala,
ETH Zurich, Institute of Computational Science (until Nov 30, 2006)
Keywords: high performance computing,
bone structure analysis, osteoporosis
This project is supported by grant #200021-113950 of the Swiss
National Science Foundation.
Osteoporosis is a disease characterized by low bone mass and
deterioration of bone microarchitecture. It leads to increased bone
fragility and risk of fracture, particularly of the hip, spine and
wrist. According to the WHO, lifetime risk for osteoporotic fractures
in women is close to 40%, in men about 13%. Osteoporosis is second only
to cardiovascular disease as a leading health care problem.
Osteoporotic fractures are a major cause of severe long-term pain and
physical disability, and have an enormous impact on individual, society
and health care systems.
With the advent of fast and powerful computers, simulation techniques
are becoming popular for investigating the mechanical properties of
bone. Using microstructural finite element (μFE) models generated
directly from computer reconstructions of trabecular bone it is now
possible to perform a 'virtual experiment', i.e. to simulate a
mechanical test in great detail and with high precision.
Ideally, the development of a system with microstructural resolution
below 50 micron would allow in-vivo measurement of patients at different
instances in time and at different anatomical sites. Unfortunately,
such systems are not yet available, but the resolution at peripheral
sites in now below 100 micron, a level that allows elucidation of
individual microstructural bone elements.
The resulting μFE models are computationally demanding and require
special solution schemes. The preconditioning conjugate gradient method
is the obvious solution method. However, currently used preconditioners
are in general not effective, and their quality deteriorates as the
problem sizes become large.
The goal of the proposed research is two-fold.
- We will rewrite the code that is presently used. The new code
shall be fully parallel, employing an advanced algebraic multigrid
preconditioner and a parallel file system.
With the advent of sufficiently large computers (e.g. at the Swiss
National Supercomputing Center (CSCS) in Manno) it will become possible
to solve systems of equations of up to one billion degrees of freedom.
This will enable us to calculate physiological tissue loading in whole
bones, which is of great importance in the assessment of the mechanical
competence and fracture risk of these bones.
- A second memory efficient code shall be developed that will allow
solving systems of equations of the size that are today solved routinely
on supercomputers on multiprocessors with 16 to 32 cores. It is assumed
that such machines will be the most widely used parallel machines in
five years time and available at a cost that a research group can
P. Arbenz and
"Microstructural Finite Element Analysis of Human Bone Structures".
ERCIM News 74, pp. 31-32, July 2008.
C. Bekas, A. Curioni, P. Arbenz, C. Flaig, G. H. van Lenthe,
R. Müller, A. J. Wirth:
"Extreme Scalability Challenges in Micro-Finite Element
Simulations of Human Bone".
Proc. International Supercomputing Conference ISC'08, Dresden, Germany,
June 17-20, 2008.
P. Arbenz, G. H. van Lenthe, U. Mennel, R. Müller, M. Sala:
"A Scalable Multi-level Preconditioner for Matrix-Free
μ-Finite Element Analysis of Human Bone Structures".
Internat. J. Numer. Methods Engrg. 73 (7): 927-947 (2008),
P. Arbenz, G. H. van Lenthe, U. Mennel, R. Müller, M. Sala:
"Multi-level μ-Finite Element Analysis for Human Bone Structures".
In Applied Parallel Computing: State of the Art in Scientific
Computing. B. Kågström, E. Elmroth, J. Dongarra, and
J. Waśniewski (eds.).
Lecture Notes in Computer Science 4699, pp.240-250. Springer,
Berlin, 2007, doi:10.1007/978-3-540-75755-9_30.
T. L. Mueller, A. J. Wirth, R. Müller, G. H. van Lenthe:
"Computational Bone Mechanics to Determine Bone Strength of the Human
16th Annual Symposium on Computational
Methods in Orthopaedic Biomechanics Pre-ORS,
UCSF, San Francisco, CA, March, 2008.
A. Wirth, T. L. Mueller, U. Mennel, M. Sala,
P. Arbenz, G. H. van
Lenthe, R. Müller:
"Stability Of Bone-Implant Constructs: A Computational Mechanics
Approach Based On High Resolution Computed Tomography".
15th Annual Symposium on Computational
Methods in Biomechanics Pre-ORS,
UCSD, San Diego, CA, February 2007.
- A. Wirth, T. L. Mueller, G. H. van Lenthe, J. Goldhahn, J. Schense,
J. Watson, V. Jamieson, P. Messmer, O. Trentz, D. Uebelhart, D.
Weishaupt, M. Egermann, and R. Müller. In vivo assessment of
mechanical stability during fracture healing in humans. 53rd Annual
Meeting of the Orthopaedic Research Society; San Diego, USA; p. 1273,
- A. Wirth, T. L. Mueller, G. H. van Lenthe, J. Goldhahn,
J. Schense, J. Watson, V. Jamieson, P. Messmer, O. Trentz, D.
Uebelhart, D. Weishaupt, M. Egermann, and R. Müller.
Computational assessment of mechanical stability during fracture
healing in humans based on high-resolution medical images. European
Society of Biomechanics Workshop 2007; Dublin, Ireland; 2007
- A. Cohen, D. Dempster, R. Müller, E. Guo, X. H. Zhang, A. J.
Wirth, G. H. van Lenthe, X. D. McMahon, H. Zhou, M. R. Rubin, J. P
Bilezikian, R. R. Recker, E. Shane. High resolution peripheral
quantitative CT (HRpQCT) of the radius reflects iliac crest biopsy
measures of microstructure and mechanical competence. Annual Meeting
of the American Society for Bone and Mineral Research; Honolulu, USA;
- A. J. Wirth, T. L. Mueller, R. Müller, P. Arbenz, G. H. van
Fast and automated analyses of bone-implant function from medical
images using high-performance computing. 2007 Annual Meeting, Swiss
Society for Biomedical Engineering; Neuchatel, Switzerland; 2007
Prof. Dr. Peter Arbenz
Institute of Computational Science
Universitätsstrasse 6, CAB G69.3
Tel.: +41 44 632 74 32
Last update: 10 November 2008