Subchondral bone plate
The subchondral bone plate is composed of two layers that separate articular cartilage from the marrow-containing cancellous bone. The superficial layer consists of calcified cartilage, which is separated by the cement line (tidemark) from the deep layer of compact cortical bone .
Radiographic features
Subchondral bone plate appears as one structure on MRI in routine clinical use, i.e. the calcified cartilage layer cannot be separate from subchondral bone .
Chemical shift artifact can result in artifactual thickening of the subchondral bone plate .