An experimentally validated micromechanical model of a rat vertebra under compressive loading.
In recent years, finite element analysis (FEA) has been increasingly applied to examine and predict the mechanical behaviour of craniofacial and other bony structures. Traditional methods used to determine material properties and validate finite element models (FEMs) have met with variable success, and can be time-consuming. An implicit assumption underlying many FE studies is that relatively high localized stress/strain magnitudes identified in FEMs are likely to predict material failure. Here we present a new approach that may offer some advantages over previous approaches. Recently developed technology now allows us to both image and conduct mechanical tests on samples in situ using a materials testing stage (MTS) fitted inside the microCT scanner. Thus, micro-finite element models can be created and validated using both quantitative and qualitative means. In this study, a rat vertebra was tested under compressive loading until failure using an MTS. MicroCT imaging of the vertebra before mechanical testing was used to create a high resolution finite element model of the vertebra. Load-displacement data recorded during the test were used to calculate the effective Young's modulus of the bone (found to be 128 MPa). The microCT image of the compressed vertebra was used to assess the predictive qualities of the FE model. The model showed the highest stress concentrations in the areas that failed during the test. Clearly, our analyses do not directly address biomechanics of the craniofacial region; however, the methodology adopted here could easily be applied to examine the properties and behaviour of specific craniofacial structures, or whole craniofacial regions of small vertebrates. Experimentally validated micro-FE analyses are a powerful method in the study of materials with complex microstructures such as bone.
Tsafnat
Naomi
N
Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, NSW, Sydney, Australia. n.tsafnat@unsw.edu.au
Wroe
Stephen
S
D000818:Animals; D001696:Biomechanical Phenomena; D019245:Compressive Strength / Q000502:physiology*; D003198:Computer Simulation; D020342:Finite Element Analysis; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D008954:Models, Biological; D051381:Rats; D013131:Spine / Q000502:physiology*; D013314:Stress, Mechanical; D055114:X-Ray Microtomography / Q000379:methods*
Drug Discov Today Technol. 2006 Summer;3(2):221-9
24980411
Nature. 2001 Feb 22;409(6823):1033-7
11234010
J Prosthet Dent. 1999 Mar;81(3):345-55
10050124
Aust Dent J. 2002 Sep;47(3):218-22
12405461
Clin Orthop Surg. 2009 Mar;1(1):40-7
19884996
J Biomech. 2009 Feb 9;42(3):234-41
19118831
J Biomech. 2010 Mar 22;43(5):1011-5
19942221
J Biomech. 1999 Apr;32(4):437-41
10213035
Med Eng Phys. 2004 Jan;26(1):61-9
14644599
Dent Mater. 2000 Nov;16(6):412-9
10967190
J Evol Biol. 2009 Nov;22(11):2278-87
19796083
Acta Otolaryngol. 2007 Jun;127(6):568-73
17503224
J Electron Microsc (Tokyo). 2006 Jun;55(3):151-5
16775217
Nat Rev Rheumatol. 2009 Jul;5(7):373-81
19568252
Adv Exp Med Biol. 2001;496:21-30
11783621
Anat Rec A Discov Mol Cell Evol Biol. 2005 Apr;283(2):275-87
15747346
Anat Rec (Hoboken). 2007 Oct;290(10):1248-55
17847056
J Biomech. 1995 Jan;28(1):69-81
7852443
Annu Rev Biomed Eng. 2004;6:185-208
15255767
Comput Methods Programs Biomed. 2009 Jul;95(1):23-30
19231021
Dent Mater. 2007 May;23(5):539-48
16730058
J Struct Biol. 2009 Dec;168(3):511-20
19635570
Bone. 1996 May;18(5):417-28
8739899
J Biomech. 2007;40(16):3688-99
17706228
J Biomed Mater Res. 1999 Apr;45(1):48-54
10397957
J Biomech. 2001 Dec;34(12):1649-54
11716868
Proc Natl Acad Sci U S A. 2007 Oct 9;104(41):16010-5
17911253
J Biomed Eng. 1990 Sep;12(5):389-97
2214726
Calcif Tissue Int. 2005 Dec;77(6):386-94
16362460
Bone. 2006 Aug;39(2):276-82
16617039
Bone. 2005 Mar;36(3):480-8
15777656
Med Eng Phys. 1998 Jan;20(1):1-10
9664280
Annu Rev Biomed Eng. 2001;3:307-33
11447066
J Biomech. 2002 Feb;35(2):161-5
11784534
J Biomech Eng. 2005 Dec;127(7):1046-53
16502646
Bone. 2006 Aug;39(2):392-400
16644297
J Anat. 2007 Jan;210(1):41-53
17229282
J Biomed Mater Res A. 2006 May;77(2):426-35
16392128
Stud Health Technol Inform. 1997;40:97-112
10168885
Methods. 2010 Jan;50(1):2-13
19706326
Anat Rec A Discov Mol Cell Evol Biol. 2005 Apr;283(2):319-30
15747350
Curr Osteoporos Rep. 2003 Jun;1(1):11-9
16036060
Proc Biol Sci. 2007 Nov 22;274(1627):2819-28
17785272