Bone mechanics heterogeneity

Biomineralization. In biomineralization, inorganic elements are extracted from the environment and selectively precipitated by organisms. Usually, templates consisting of suitable macro-molecules serve as a substrate for the heterogeneous nu-cleation of bulk mineralized structures such as bone, teeth and shells. Biological control mechanisms are reflected not only in the type of the mineral phase formed but also in its morphology and crystallographic orientation (Mann et al., 1989 Lowenstamm and Weiner, 1989). Two examples (perhaps oversimplified) may illustrate the principle (Ochial, 1991) ... 

Osteopetrosis (marble bone disease) is marked by the formation of abnormally dense and condensed bone. It is a genetically, biochemically, and clinically heterogeneous disease. However, the underlying mechanism for the various types of osteopetrosis is a failure in bone resorption due to defects in osteoclasts. In some forms of osteopetrosis, providing normal osteoclastic precursors by bone marrow transplantation has yielded clinical improvement. Stimulation of osteoclast formation or activity with 1, 25-(0H)2D or recombinant interferon-y also has yielded modest clinical improvement. 

Carretta, R. et al. (2013) Within subject heterogeneity in tissue-level post-yield mechanical and material properties in human trabecular bone. J. Mech. Behav. Biomed. Mater., 24, 64-73. 

---