Linked Life Data

11858807

Source:http://linkedlifedata.com/resource/pubmed/id/11858807

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2002-3-7
pubmed:abstractText
A new finite element model (FEM) based on an elasto-plastic behavior of ultra high molecular weight polyethylene (UHMWPE) was used to study the wear behavior of UHMWPE acetabular cup, which has a 32 mm diameter femoral head. The model imposed a plastic yield stress of 8 MPa on the UHMWPE so that any stresses beyond this would automatically be redistributed to its neighbor. The FEM model adopted a unique mesh design based on an open cube concept which eliminated the problems of singularities. Wear prediction combined the influences of contact stress, sliding distance and a surface wear coefficient. The new model predicted significantly higher volumetric wear rate (57 mm(3)/yr) well within the average reported clinical values. The model was also used to study the effect of friction and clearance between the acetabular cup and the femoral head. Increase in friction increased the volumetric wear rate but did not appear to affect the linear wear rate, which remained at 0.12 +/- 0.02 mm/yr. The predicted wear was sensitive to clearance. It was found that when the clearance was close to 0 and >0.5mm, severe wear occurred. The best clearance range was between 0.1 and 0.15 mm where the average linear wear rate was 0.1mm/yr and the volumetric wear was 55 mm(3)/yr. The present work indicates the importance of avoiding too tight or too loose a diametrical clearance.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0021-9290
pubmed:author
pubmed:issnType
Print
pubmed:volume
35
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
323-30
pubmed:dateRevised
2009-11-11
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
An elasto-plastic finite element model for polyethylene wear in total hip arthroplasty.
pubmed:affiliation
Laboratory for Biomedical Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260, Singapore. mpetsh@nus.edu.sg
pubmed:publicationType
Journal Article, Comparative Study