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Current Osteoporosis Reports

, Volume 3, Issue 2, pp 39–45 | Cite as

Microcracks in cortical bone: How do they affect bone biology?

  • Fergal J. O’Brien
  • Orlaith Brennan
  • Oran D. Kennedy
  • T. Clive Lee
Article

Abstract

Microcrack accumulation in cortical bone has been implicated in skeletal fragility and stress fractures. These cracks have also been shown to affect the mechanical and material properties of cortical bone. Their growth has been linked to osteocyte apoptosis and the initiation of the remodeling process, which also has a role in their repair. Clinically, osteoporosis is diagnosed using dual energy x-ray absorptiometry. However, evidence now indicates that bone mass alone is insufficient to satisfactorily explain the skeletal fragility of osteoporosis and consideration needs to be given to bone quality in the diagnosis and treatment of the disease. Bone quality includes parameters such as trabecular and cortical microarchitecture, morphology, bone turnover, degree of mineralization of the bone matrix, and significantly, the amount of microdamage present in the bone. Current clinical treatments concentrate on the inhibition of osteoclast activity to maintain bone mass in osteoporotic patients. However, these cells have a major role in removing existing microcracks from the bone matrix, and hence the use of bone resorption-inhibiting drugs may lead to insufficient bone repair and therefore an increase in microdamage accumulation and loss of bone quality.

Keywords

Osteoporosis Cortical Bone Risedronate Etidronate Fluid Shear Stress 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Current Science Inc 2005

Authors and Affiliations

  • Fergal J. O’Brien
    • 1
  • Orlaith Brennan
  • Oran D. Kennedy
  • T. Clive Lee
  1. 1.Department of AnatomyRoyal College of Surgeons in IrelandDublin 2Ireland

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