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01-06-2012 | Skeletal Regulations (D Gaddy, Section Editor)

The Contribution of the Extracellular Matrix to the Fracture Resistance of Bone

Authors: Jeffry S. Nyman, Alexander J. Makowski

Published in: Current Osteoporosis Reports | Issue 2/2012

Abstract

The likelihood of suffering a bone fracture is not solely predicated on areal bone mineral density. As people age, there are numerous changes to the skeleton occurring at multiple length scales (from millimeters to submicron scales) that reduce the ability of bone to resist fracture. Herein is a review of the current knowledge about the role of the extracellular matrix (ECM) in this resistance, with emphasis on engineering principles that characterize fracture resistance beyond bone strength to include bone toughness and fracture toughness. These measurements of the capacity to dissipate energy and to resist crack propagation during failure precipitously decline with age. An age-related loss in collagen integrity is strongly associated with decreases in these mechanical properties. One potential cause for this deleterious change in the ECM is an increase in advanced glycation end products, which accumulate with aging through nonenzymatic collagen crosslinking. Potential regulators and diagnostic tools of the ECM with respect to fracture resistance are also discussed.

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Title: The Contribution of the Extracellular Matrix to the Fracture Resistance of Bone
Authors: Jeffry S. Nyman
Alexander J. Makowski
Publication date: 01-06-2012
Publisher: Current Science Inc.
Published in: Current Osteoporosis Reports / Issue 2/2012
Print ISSN: 1544-1873
Electronic ISSN: 1544-2241
DOI: https://doi.org/10.1007/s11914-012-0101-8

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