Microstructural changes of the joint cartilage are a significant morphological correlate of patholo- gical process. Successful detection of their primary symptoms requires both detailed knowledge of structure of particular cartilage layers and the use of suitable histological techniques. In the literature there are fundamental discrepancies in the description of the superficial chondral membrane (lamina splendens) as well as in the orientation of collagen fibrils running in the horizontal layer and their attachment in the lamina splendens. We investigated the horizontal layer of the hog knee cartilage with respect to the lamina splendens. For orientation in the whole thickness of the joint cartilage, sections stained for collagen were studied under the polarization microscope; the course and the orientation of particular fibrils are apparent in the transmission electron microscope. The clearly distinct lamina splendens appears as a homogeneous acellular layer under the polarization microscope, being finely granular with fibrils running in all directions parallel to the articular surface in the transmission electron microscope. The resultant model is used for the description of articular cartilage surface changes after experimentally introduced fissures (split line).

        Key words: joint cartilage, lamina splendens, split line