Abstract/Details

The effect of bone turnover on bone quality and material properties

Kennedy, O. D.   Trinity College Dublin (University of Dublin) (Ireland) ProQuest Dissertations Publishing,  2008. U491764.

Abstract (summary)

This study sought to characterise the effect of bone turnover on bone quality and material properties, in an ovariectomised (OVX) ovine animal model at 12 months post-surgery.   A study of compact bone turnover and microarchitecture, using epifluorescence microscopy and micro CT respectively, was carried out on the left metatarsal.  Bone turnover was increased in the OVX group compared with controls.  Increased turnover resulted in increased porosity in the OVX group compared to controls. The small reduction in strength resulting from these changes compared well with our calculations which were based on the reduction in load bearing area. Analyses of fatigue-induced microdamage in control and OVX compact bone samples showed that while numerical crack density was higher in OVX, crack surface density was higher in the controls, due to the presence of more long microcracks.  It was also observed that long cracks (>300μm) tended to stop at new (labelled) osteons whereas they tended to penetrate or deflect around older (unlabelled) osteons.  This shows that increased turnover has a direct effect on microcrack behaviour in bone. Histomorphometry of the L3 vertebra revealed increased bone turnover in cortical and trabecular compartments in OVX bone compared with controls.  Biomechanical testing showed that ultimate strength and stiffness were reduced in the OVX group.  This group also displayed less plastic strain and more strain due to damage compared with controls.   Although no change was found in BMD as measured by DEXA, significant changes were found in bone quality parameters 12 months post-OVX.  In conclusion, this study has illustrated the importance of bone turnover in relation to bone quality.

Indexing (details)


Subject
Medicine
Classification
0564: Medicine
Identifier / keyword
(UMI)AAIU491764; Health and environmental sciences
Title
The effect of bone turnover on bone quality and material properties
Author
Kennedy, O. D.
Number of pages
1
Degree date
2008
School code
0770
Source
DAI-C 71/97, Dissertation Abstracts International
Place of publication
Ann Arbor
Country of publication
United States
University/institution
Trinity College Dublin (University of Dublin) (Ireland)
University location
Ireland
Degree
Ph.D.
Source type
Dissertation or Thesis
Language
English
Document type
Dissertation/Thesis
Dissertation/thesis number
U491764
ProQuest document ID
301700450
Copyright
Database copyright ProQuest LLC; ProQuest does not claim copyright in the individual underlying works.
Document URL
https://www.proquest.com/docview/301700450