Characterization of OA Severity in Knee Articular Cartilage in-Vivo Using MR Imaging and Loading Techniques

Simple item page
atmire.migration.oldid5879
dc.contributor.advisorRonsky, Janet Lenore
dc.contributor.authorDai, Xu
dc.contributor.committeememberFrayne, Richard
dc.contributor.committeememberSchmidt, Tannin
dc.contributor.committeememberBoyd, Steven Kyle
dc.contributor.committeememberNowicki, Edwin Peter
dc.contributor.committeememberHoldsworth, David W.
dc.date.accessioned2017-08-23T16:31:31Z
dc.date.available2017-08-23T16:31:31Z
dc.date.issued2017
dc.date.submitted2017en
dc.description.abstractEarly osteoarthritis (OA) is primarily associated with proteoglycan (PG) loss and changes in collagen structure. MR T2 imaging of knee under in-vivo loading may help to further reveal the differences between healthy and OA cartilage. This study investigated the in-vivo loading effect on MR T2 values of human knee patellar cartilage. The results demonstrated T2 value distributions in patellar cartilage were inhomogeneous. In-vivo loading had a site-specific influence on participants’ T2 values. The in-vivo loading produced a significant difference on T2 values in the middle region of interest (ROI) of patellar cartilage (p=0.004＜0.025), but not at the superior or inferior ROIs. The T2 value variation for the OA group during loading was lower than that of the healthy group (p=0.016＜0.025). The T2 recovery ratio was presented in this study as a new variable. The findings indicated the T2 recovery ratio of the OA group was significantly lower than the healthy group (p=0.042＜0.05) in the patellar cartilage middle ROI. It suggests that the OA cartilage had weaker ability to restore its original status after off-loading than healthy cartilage. This study examined the glycosaminoglycan (GAG) mass% concentration (relating PG) in human cadaveric patellar cartilages using biochemical assay. Results showed that the GAG mass% concentrations in OA lesion positions were lower than that in comparative healthy positions (p＜0.001). MR T2 imaging of healthy and OA cadaver knee joints were performed. Correlations between T2 values and the GAG mass(%) of cadaver patellar cartilage specimens were established. As PG concentration of in-vivo human articular cartilage cannot be directly measured non-invasively, the correlation of cadaveric patellar cartilage may serve as an important bridge between the T2 value and GAG mass% for living human assessment. The findings provide an indirect approach to estimate PG concentration of in-vivo patellar cartilage based on an individual’s cartilage T2 values to evaluate the extent of degradation within cartilage. This subject specific method is especially suitable for longitudinal evaluation of OA. By position-matched comparison of previous and current T2 images, the GAG mass% variation may be estimated to assess OA progression non-invasively.en_US
dc.identifier.citationDai, X. (2017). Characterization of OA Severity in Knee Articular Cartilage in-Vivo Using MR Imaging and Loading Techniques (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/25283en_US
dc.identifier.doihttp://dx.doi.org/10.11575/PRISM/25283
dc.identifier.urihttp://hdl.handle.net/11023/4031
dc.language.isoeng
dc.publisher.facultyGraduate Studies
dc.publisher.institutionUniversity of Calgaryen
dc.publisher.placeCalgaryen
dc.rightsUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.
dc.subjectEngineering--Biomedical
dc.subject.otherOsteoarthritis
dc.subject.otherpatellar cartilage
dc.subject.otherMR T2 imaging
dc.subject.otherin-vivo loading
dc.subject.otherproteoglycan
dc.titleCharacterization of OA Severity in Knee Articular Cartilage in-Vivo Using MR Imaging and Loading Techniques
dc.typedoctoral thesis
thesis.degree.disciplineBiomedical Engineering
thesis.degree.grantorUniversity of Calgary
thesis.degree.nameDoctor of Philosophy (PhD)
ucalgary.item.requestcopytrue
Files
Collections
Open Theses and Dissertations