Bone structure and properties
Distinct loading conditions influence the development of
macroscopically diverse bony structures in vivo with carefully tailored
shapes, mechanical properties, and spatial distributions. More than 206
different bones make up the skeleton, ranging from the long bones
found in our limbs, short bones in the wrist and ankle, and flat bones
in the sternum and skull, to irregular bones such as the pelvis and
vertebrae. Bone tissue itself is arranged either in a compact pattern
(cortical bone) or a trabecular pattern (cancellous bone)7.
As with all organs in the body, bone tissue has a hierarchical
organization over length scales that span several orders of magnitude
from the macro- (centimeter) scale to the nanostructured (extracellular
matrix or ECM) components (Fig. 1). Bone ECM comprises both a
nonmineralized organic component (predominantly type-1 collagen)
and a mineralized inorganic component (composed of 4 nm thick platelike
carbonated apatite mineralites)8. In addition, over 200 different
types of noncollagenous matrix proteins (glycoproteins, proteoglycans,
and sialoproteins) contribute to the abundance of signals in the
immediate extracellular environment. The nanocomposite structure
(tough and flexible collagen fibers reinforced by hydroxyapatite, HA,
crystals) is integral to the requisite compressive strength and high
fracture toughness of bone.
Bone structure and propertiesDistinct loading conditions influence the development ofmacroscopically diverse bony structures in vivo with carefully tailoredshapes, mechanical properties, and spatial distributions. More than 206different bones make up the skeleton, ranging from the long bonesfound in our limbs, short bones in the wrist and ankle, and flat bonesin the sternum and skull, to irregular bones such as the pelvis andvertebrae. Bone tissue itself is arranged either in a compact pattern(cortical bone) or a trabecular pattern (cancellous bone)7.As with all organs in the body, bone tissue has a hierarchicalorganization over length scales that span several orders of magnitudefrom the macro- (centimeter) scale to the nanostructured (extracellularmatrix or ECM) components (Fig. 1). Bone ECM comprises both anonmineralized organic component (predominantly type-1 collagen)and a mineralized inorganic component (composed of 4 nm thick platelikecarbonated apatite mineralites)8. In addition, over 200 differenttypes of noncollagenous matrix proteins (glycoproteins, proteoglycans,and sialoproteins) contribute to the abundance of signals in theimmediate extracellular environment. The nanocomposite structure(tough and flexible collagen fibers reinforced by hydroxyapatite, HA,crystals) is integral to the requisite compressive strength and highfracture toughness of bone.
การแปล กรุณารอสักครู่..
