[The cartilage in nuclear magnetic resonance tomography]

Comparison of MRI tomograms with anatomic sections shows that the limits of the joint cartilage do not correspond to the hitherto assumed zone of the more intensive signal. This intensive signal may be caused merely by the surface of the cartilage. Considering its extent, the signal-free zone bordering on this zone should also be cartilage. Since, e.g., in the knee, there is no subchondral substantia corticalis and, as is clearly recognizable in the anatomic section, bone marrow extends as far as the cartilage, this signal-poor zone should also correspond, at least in part, to cartilage. It is conceivable that the boundary areas in the MRI tomogram (in this case the cartilage surface) are demonstrated and that the signal behavior of the hyaline joint cartilage is not uniform and applicable to all sections. This also applies to fibrous cartilage.