Linked Life Data

8894927

Source:http://linkedlifedata.com/resource/pubmed/id/8894927

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1997-1-23
pubmed:abstractText
Very few quantitative comparisons between mechanical test behavior of cortical bone and microscopic evidence of damage have been reported. In this study, the hypothesis that age-related degradation of mechanical properties in human cortical bone is associated with increases in damage in the form of microcracks was investigated. The initial modulus and yield stress were 6% (not significant) and 10% (p = 0.05) lower, respectively, in specimens from elderly femora than in specimens from young adult femora. However, both groups showed a 34% decrease in modulus after being loaded to 1% strain. Microcracks were observed in cement lines and between lamellae and were parallel to the loading direction. There were 50% more cracks in longitudinal sections of tested specimens than in controls from elderly femora; however, there were no more cracks in tested specimens than in controls from young adult femora. In addition, there were twice as many cracks in controls and three times as many cracks in tested specimens from elderly femora than in those from young adult femora (p < 0.01). A microstructurally based model was developed which supported the mechanical test results and indicated that damage began to develop at about 1500 mu epsilon. The results suggest that older bone may have reduced mechanical properties due to the presence of more microcracks, and that older bone is more susceptible to developing microcracks at a given strain level. However, the mechanical test data indicate that specimens from young adult femora also sustained some king of damage as a result of mechanical loading, which requires further investigation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0021-9290
pubmed:author
pubmed:issnType
Print
pubmed:volume
29
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1463-71
pubmed:dateRevised
2009-11-11
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Age-related differences in post-yield damage in human cortical bone. Experiment and model.
pubmed:affiliation
Department of Orthopedic Research, Charles A. Dana Research Institute, Harvard-Thorndike Biomechanics Laboratory, Beth Israel Hospital, Boston, MA, USA.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't