Ontogenetic changes in the mechanical properties of the femur of the polar bear <em>Ursus maritimus</em>

Brear, K.; Currey, J. D.; Pond, Caroline M.

Affiliations

¹Department of Biology, University of York, UK

²Department of Biology, The Open University, Milton Keynes, UK

Abstract

The mechanical properties of the bone material of femora of five wild polar bears, ranging in age from three months to seven and three-quarter years, were compared with those of humans and axis deer. There are changes in mechanical properties in all three species with age, but their time course and extent vary greatly between species. The age-related changes in mechanical properties are attributable mainly to changes in mineralization. At any age, the properties of the polar bear's bones lie between those of humans and the deer. The architecture of the bear's bones, and the mechanical properties of their bone material, were related to the weight of the bears. The calculated stresses in the bones, and their deflection under load, were relatively constant compared with the very large differences in the weights of the bears and the sizes of their bones.

Links

DOI: 10.1111/j.1469-7998.1990.tb04028.x

WoS: A1990ED48800004

History

Accepted: 1989-08-23

Cited Works (12)

Year	Entry
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1967	Sarkar BCR, Chauhan UPS. A new method for determining micro quantities of calcium in biological materials. Anal Ciochem. July 1967;20(1):155-166.
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Cited By (15)

Year	Entry
2001	Currey JD. Ontogenetic changes in compact bone material properties. In: Cowin SC, ed. Bone Mechanics Handbook. 2nd ed. Boca Raton, FL: CRC Press; 2001:19-1–19-16.
2002	Currey JD. Bones: Structure and Mechanics. Princeton, NJ: Princeton University Press; 2002.
1990	Currey JD. Function and form of bone. In: Mow VC, Ratcliffe A, Woo SL-Y, eds. Biomechanics of Diarthrodial Joints. Vol 2. New York, NY: Springer-Verlag; 1990:3-30.
2004	Akkus O, Adar F, Schaffler MB. Age-related changes in physicochemical properties of mineral crystals are related to impaired mechanical function of cortical bone. Bone. March 2004;34(4):443-453.
1994	Currey JD, Brear K, Zioupos P. Dependence of mechanical properties on fibre angle in narwhal tusk, a highly oriented biological composite. J Biomech. July 1994;27(7):885-897.
1996	Currey JD, Brear K, Zioupos P. The effects of ageing and changes in mineral content in degrading the toughness of human femora. J Biomech. February 1996;29(2):257-260.
2003	Currey JD. The many adaptations of bone. J Biomech. 2003;36(10):1487-1495.
2010	Main RP, Lynch ME, van der Meulen MCH. In vivo tibial stiffness is maintained by whole bone morphology and cross-sectional geometry in growing female mice. J Biomech. October 19, 2010;43(14):2689-2694.
2005	Tommasini SM, Nasser P, Schaffler MB, Jepsen KJ. Relationship between bone morphology and bone quality in male tibias: implications for stress fracture risk. J Bone Miner Res. August 2005;20(8):1372-1380.
1999	Currey JD. The design of mineralised hard tissues for their mechanical functions. J Exp Biol. December 1999;202(23):3285-3294.
2008	Tommasini SM. Phenotypic Integration Contributes to Skeletal Functionality and Fragility [PhD thesis]. New York, NY: The City University of New York; 2008.
2006	Main RP. Skeletal Mechanics, Bone Histomorphology, and Growth in Tetrapods [PhD thesis]. Cambridge, MA: Harvard University; September 2006.
1995	Heinrich RE. Functional Morphology and Body Size of Early Tertiary Miacoidea (mammalia, Carnivora) [PhD thesis]. Johns Hopkins University; 1995.
2008	Price C. Systems Based Approaches to Identifying How Genetically Varying Skeletal Growth Affects Skeletal Functionality and Fragility [PhD thesis]. Mount Sinai School of Medicine; 2008.
2010	Joiner DM. The Effect of Age on Bone and Its Response to Mechanical Stimulation [PhD thesis]. University of Michigan; 2010.