[Pressure devices for NMR microscopy studies of the loading behavior of articular cartilage]

High-resolution MRI offers a unique opportunity to non-invasively image collagen-mediated structures within articular cartilage. Visualization of the stress response of the anisotropic collagenous network in particular, provides more comprehensive knowledge of the biomechanical properties and integrity of articular cartilage, which in turn form a very promising starting point for the present ongoing developments in the noninvasive diagnosis of early stages or arthrosis. The detection of stress-induced changes in the collagenous network, however, requires an MRI probe that permits in vitro measurements under conditions similar to those in the joint, and different orientations relative to the static magnetic field. Here we describe two MR microimaging probes that enable the investigation of the viscoelastic properties of articular cartilage via visualization of the pressure-dependent modifications of anisotropic collagenous structures.