Glen L Niebur
Summary of Activities/Interests
We are studying the biomechanics of bone as it relates to aging and osteoporosis. Our focus over the past five years has been the effects of damage accumulation on bone. Using microscopy and micro-Computed Tomography, we have measured microstructural damage in bone, including small cracks and cross-hatching patterns, that occur during overloading or fatigue loading of bone. In collaboration with Colorado State University, we have investigated the effects of simulated osteoporosis on damage mechanics in old female sheep.
Bone marrow biomechanics
We are studying the interaction of bone and bone marrow to better understand the mechanical influences on the many cells that are resident in the bone marrow. Bone marrow composition changes with aging, with the primary alteration being an increase in the proportion of fat cells. The increase in the number of fat cells may decrease the number of available adult stem cells that can form new bone cells. As such, there could be a causal link between aging of the bone marrow and the surrounding bone.
Ph.D. - University of California at Berkeley, 2000
M.S.M.E. - University of Minnesota, 1995
B.M.E. - University of Minnesota, 1986
Glen Niebur is associate professor of Aerospace and Mechanical Engineering at the University of Notre Dame. He holds bachelor’s and master’s degrees from the University of Minnesota, and the Ph.D. from the University of California. Research is focused on orthopaedics, including bone quality, damage mechanics of trabecular bone, lumbar spinal fusion, hard and soft tissue constitutive modeling, computational mechanics, of tissues, and genetic factors affecting bone quality.
Current projects are investigating the interactions between microdamage formation in bone and the changes in bone porosity and structure that accompany osteoporosis. Osteoporosis results in changes at multiple levels of the hierarchical structure of bone, and these can either compensate for or enhance fracture risk. Medical imaging methods, especially computed tomography (CT) are used to image and quantify bone structures in bone samples and in live animals. A current project is using medical imaging to longitudinally monitor and understand fracture healing. Most recently, work has begun in the area of bone marrow mechanics, affects of aging and disease on bone marrow morphology, and interactions between bone and bone marrow.
For more details see: http://tml.ame.nd.edu
- Coughlin TR, Niebur GL, 2012, " Fluid Shear Stress in Trabecular Bone Marrow due to Low-Magnitude High-Frequency Vibration. " Journal of Biomechanics, 45:2222-2229
- Birmingham E, Niebur GL, McHugh PE, Shaw G, Barry FP, McNamara LM, 2012 " Osteogenic differentiation of mesenchymal stem cells is regulated by osteocyte and osteoblast cells in a simplified bone niche " European Cells and Materials, 23:13-27 Highlighted as top story in Mesenchymal Cell News
- Wu, Z, Ovaert, TC, and Niebur, GL, 2011, " Viscoelastic properties of human cortical bone tissue depend on gender and modulus " Journal of Orthopaedic Research, doi: 10.1002/jor.22001
- Shepherd TN, Zhang, J, Ovaert, TC, Niebur GL, 2011, " Direct comparison of nanoindentation and macroscopic measurements of bone viscoelasticity " Journal of the Mechanical Behavior of Biomedical Materials 4(8): 2055-62
- Garrison, JG, Gargac, JA, Niebur GL, 2011, " Shear strength and toughness of trabecular bone are more sensitive to density than damage. " Journal of Biomechanics 44(16): 2747-54
- Wu, Z, Baker, T, Ovaert, TC, and Niebur GL, 2011, " The effect of holding time on on nanoindentation measurements of creep in bone. " Journal of Biomechanics 44(6): 1066-72
- Shi X, Liu XS, Wang X, Guo XE, Niebur GL, 2010, " Type and orientation of yielded trabeculae during overloading of trabecular bone along orthogonal directions." Journal of Biomechanics, 43(13) pp2460-6
- Shi X, Liu XS, Wang X, Guo XE, Niebur GL, 2010, " Effects of trabecular type and orientation on microdamage susceptibility in trabecular bone. " Bone 46(5):1260.
- Korecki CL, Zinser G, Liu X, Siedler J, Welsh J, Niebur GL, 2009, " Effect of the Vitamin D Receptor on Bone Geometry and Strength During Gestation and Lactation in Mice. " Calcified Tissue International 85(5):405-11.
- Dai Y and Niebur GL, 2009, "A semi-automated method for hexahedral mesh construction of human vertebrae from CT scans." Computer Methods in Biomechanics and Biomedical Engineering 12(5):599-606
- Garrison JG, Slaboch, CL, and Niebur GL, 2009, "Density and architecture have greater effects on the toughness of trabecular bone than damage" Bone 44(5):924-9.
- Shi, X and Niebur GL, 2009, "Effects of loading orientation on the morphology of the predicted yielded regions in trabecular bone." Annals of Biomedical Engineering 27(2):354-62