Abstract:
:This study demonstrates the in vitro displacement and strain of articular cartilage in a cyclically-compressed and intact joint using displacement-encoded imaging with stimulated echoes (DENSE) and fast spin echo (FSE). Deformation and strain fields exhibited complex and heterogeneous patterns. The displacements in the loading direction ranged from -1688 to -1481 microm in the tibial cartilage and from -1601 to -764 microm in the femoral cartilage. Corresponding strains ranged from -9.8% to 0.7% and from -4.3% to 0.0%. The displacement and strain precision were determined to be 65 microm and less than 0.2%, respectively. Displacement-encoded magnetic resonance imaging is capable of determining the nonuniform displacements and strains in the articular cartilage of an intact joint to a high precision. Knowledge of these nonuniform strains is critical for the in situ characterization of normal and diseased tissue, as well as the comprehensive evaluation of repair constructs designed using regenerative medicine.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Chan DD,Neu CP,Hull MLdoi
10.1002/mrm.21927subject
Has Abstractpub_date
2009-04-01 00:00:00pages
989-93issue
4eissn
0740-3194issn
1522-2594journal_volume
61pub_type
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