Measurement of the Mechanical Properties of Bone: A Recent History

Abstract

Much progress has been made in the last 50 years in our understanding of bone's mechanical properties, and the reasons it has these properties and not others.

Influence of Gender and Fixation Stability on Bone Defect Healing in Middle-aged Rats: A Pilot Study

“…Between 2-and 4-week followup, dCSA 2-4 was higher (p = 0.005) in male compared with female animals, whereas no difference (p = 0.666) in dCSA 2-4 between semirigid and rigid fixation was observed. Between 4 and 6 weeks after surgery, only combined effects of fixation stability and gender variation influenced dCSA [4][5][6] (p = 0.005), whereas the gender alone (p = 0.848) and fixation stability alone (p = 0.672) variation did not.…”

“…Additionally, semirigid groups had superior callus properties also indicated by changes in these outcome measures. From the analysis of cancellous bone, it is known that both Young's modulus and strength depend on bone volume fraction [4]. Using this as a guide for interpretation, with superior microstructural changes such as higher Tb.N and lower Tb.Sp, for a larger BV, and Jz observed in male individuals, we conclude the differences in biomechanical callus properties are purely the result of callus volume, geometry, and microstructure but not tissue mineralization.…”

“…The cross-sectional area of each callus (CSA) was measured and expressed relative to that of the corresponding femur itself (in percentage) [24]. Intraindividual changes of CSA among Weeks 0 to 2 (dCSA 0-2 ), 2 to 4 (dCSA [2][3][4], and 4 to 6 (dCSA [4][5][6] ) were compared between the groups using a two-way ANOVA as described for mechanical testing parameters. From the microcomputed binarized images, we made the following morphometric measurements using a direct three-dimensional approach with the vendor software (Scanco software V.6; Scanco Medical AG 1 , Brüttisellen, Switzerland): (1) The statistical analysis was performed using statistics software, SPSS 17.0 (SPSS Inc, Chicago, IL) and Prism 5.0 (GraphPad Software Inc, San Diego, CA).…”

On optimal hierarchy of load-bearing biological materials

“…To obtain a comprehensive understanding of biological materials, it is particularly important to bridge observations and behaviours across several length scales [22]. So far, there have been only limited studies of biological structures from a global hierarchical point of view.…”

Biomimetics in Bone Cell Mechanotransduction: Understanding Bone’s Response to Mechanical Loading

“…Load cells range from 50 gm to 445 N; torque cell capacity is 176.5 Nmm (25 oz-in); and, displacement sensors accommodate 5 and 25 mm of travel (Saunders and Donahue, 2004). As is typical of biomechanical testing systems, machine deformation is largely unaccounted for, but assumed to be negligible given that machine stiffness is much greater than specimen stiffness (Currey, 2009). While the system is highly flexible and cost-effective, it is extremely important to acknowledge the limitations of the in-house device.…”