The osteon: the micromechanical unit of compact bone

Abstract

The research techniques available for investigation of secondary osteons in human bone enable establishment of their biological composition and quantification of their mechanical properties. Further, the data generated through current research techniques facilitate studies on the significance of osteons in normal and pathological conditions, including via multi-scale modeling conducted with a view of building realistic models of virtual bone, suitable for applications from orthopaedic challenges to endocrine disorders. The understanding of the biomechanical function of the osteon requires clarification of the molecular-cellular processes that form, maintain and remodel the osteon and affect the mechanical function. In turn, the mechanical function affects the biology of the osteon. In retrospective, the investigation of osteons has focused on the unraveling of the complex combination of elementary components to discern the major factors that define the mechanical behavior. The micro-structural environment that leads to macroscopic fracture remains unclear. Arrangement, distribution and quality of the elementary components may participate in fracture risk. The latest results underline the fundamental role of the orientation of collagen type I and of carbonated hydroxyapatite crystallites.

BMP Receptor 1A Determines the Cell Fate of the Postnatal Growth Plate

“…FITC staining 2, 5- Fluorescein isothiocyanate, a small molecular dye, fills in all non-mineralized cells/fibers. Thus, the dye provides a visual representation of the organization of the growth plate and perichondrium under the confocal microscope.…”

Microfibril Orientation Dominates the Microelastic Properties of Human Bone Tissue at the Lamellar Length Scale

“…In mature human cortical bone, the tissue takes the appearance of a mosaic of osteons, or Haversian system. Each of these fundamental remodeling units is typically 100 to 300 µm in diameter [3] and consists of several concentric lamellae, approximately 5–8 µm thick, surrounding a central canal. The term ‘bone lamella’ has been defined in several different ways in the existing literature: a lamella unit can be seen as a combination of dark/bright layers as seen under polarized light microscopy [4], a combination of thin/thick layers as observed from optical microscopy [5], several sublayers [6], [7] or the tissue between two transverse orientations of the collagen fibers [8].…”

Osteogenic effects of resveratrol in vitro: potential for the prevention and treatment of osteoporosis

“…The osteon in cortical bone is the micromechanical unit that responds to the biomechanical, endocrine, and nutritional stimuli that are responsible for the physiological maintenance of bone extracellular matrix (ECM). 1 Old bone is degraded by boneresorbing osteoclasts and is replaced with new bone produced by bone-synthesizing osteoblasts. 2 However, the delicate balance between bone synthesis and bone degradation is lost with aging, resulting in low bone density and osteoporosis.…”