Modeling in biomechanics and biomedical engineering Division of Biomechanics and Engineering Design Dept. Mechanics, K.U.Leuven, Belgium Outline Mathematical modeling of fracture healing Osteoporosis & bone structure Treatment of asthmatic patients Stent design & implantation Head impacts & bicycle helmet design 2 1
Outline Mathematical modeling of fracture healing Osteoporosis & bone structure Treatment of asthmatic patients Stent design & implantation Head impacts & bicycle helmet design 3 Mathematical modeling of fracture healing 4 2
Atrophic nonunion Geris and Reed et al., 2009. 5 Atrophic nonunion: treatment strategies Geris and Reed et al., 2009. 6 3
Mechanical loading Overload induced nonunion F F Geris et al., 2009. 7 Mechanical loading: treatment strategies F Geris et al., 2009. 8 4
Outline Mathematical modeling of fracture healing Osteoporosis & bone structure Treatment of asthmatic patients Stent design & implantation Head impacts & bicycle helmet design 9 Bone structure-function relationship µct FE model Calculation of bone strains Courtesy of G.H. Van Lenthe 10 5
Bone structure-function relationship In vivo assessment of bone quality Courtesy of G.H. Van Lenthe 11 Outline Mathematical modelling of fracture healing Osteoporosis & bone structure Treatment of asthmatic patients Stent design & implantation Head impacts & bicycle helmet design 12 6
Treatment of asthmatic patients Acute effect of bronchodilator Application of the technique in a phase II study of a new 24h active LABA (Carmoterol) Use of advanced imaging and CFD to assess acute effect of the new compound 10 subjects and 4 controls Subjects: PRE and POST scan (4 hours after administration of product) Controls: PRE and POST scan after 24h washout period Scans are taken at Total Lung Capacity (TLC) De Backer et al., J. Biomech., 2008. 13 Treatment of asthmatic patients Reconstruction of airway morphology pre-dose post-dose De Backer et al., J. Biomech., 2008. 14 7
Treatment of asthmatic patients Treated patient Control patient De Backer et al., J. Biomech., 2008. 15 Treatment of asthmatic patients Treated patient Control patient De Backer et al., J. Biomech., 2008. 16 8
Outline Mathematical modeling of fracture healing Osteoporosis & bone structure Treatment of asthmatic patients Stent design & implantation Head impacts & bicycle helmet design 17 Stent design & implantation Narrowing of coronary arteries Bypass Stent 18 18 9
Stent design & implantation Experimental research Computer simulations Flow Structure Courtesy of M. De Beule 19 19 Stent design & implantation Stent design Diameter [mm] 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.0 0.4 0.8 1.2 1.6 Pressure [Mpa] De Beule et al., J. Biomech., 2008. Mortier et al., J. Biomech. Eng., 2008. 20 20 10
Stent design & implantation Simulation of stent expansion 3.5 Diameter [mm] 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0.0 0.4 0.8 1.2 1.6 Pressure [Mpa] De Beule et al., J. Biomech., 2008. Mortier et al., J. Biomech. Eng., 2008. 21 21 Stent design & implantation From design to clinic: stress calculation after patient specific stenting Courtesy of M. De Beule22 22 11
Outline Mathematical modeling of fracture healing Osteoporosis & bone structure Treatment of asthmatic patients Stent design & implantation Head impacts & bicycle helmet design 23 Head impacts & bicycle helmet design Dublin FE head model Horgan & Gilchrist, Int. J. Crash., 2003. 24 12
Head impacts & bicycle helmet design Detailed modeling of helmet during impact Helmet deformation and movement visualization Courtesy of A.G. Asiminei 25 Head impacts & bicycle helmet design Detailed modeling of brain movement inside skull Brain stress visualization Courtesy of K. Baeck 26 13
Head impacts & bicycle helmet design Detailed modeling of skull vibration during impact Skull mode shape visualization Courtesy of E. Forausberger 27 Conclusion Biomechanics & biomedical technology field increasingly focused on: patient-specific causes of failure of structures & processes patient-specific prevention, therapeutic tools & treatment strategies Computations not feasible on single servers HPC infrastructure needed to obtain results within reasonable time frame 28 14
Acknowledgements Harry van Lenthe, Esmeralda Forausberger, Katrien Baeck, Aida Georgeta Asiminei, Luiza Muraru, Georges Van der Perre, Hans Van Oosterwyck, Jos Vander Sloten (K.U.Leuven) http://www.mech.kuleuven.be/bmgo Matthieu De Beule, Peter Mortier, Patrick Segers, Pascal Verdonck, Benedict Verhegghe (UGent) http://www.ibitech.ugent.be Jan De Backer, Wim Vos, Annick Devolder, Stijn Verhulst, Paul Germonpré, Floris Wuyts, Paul Parizel, Wilfried De Backer (UA) http://www.ua.ac.be, http://www.fluidda.com 29 15