Section of the anterior cruciate ligament of the right knee was performed in 20 rabbits which were sacrificed 3 months later. During that time, 10 animals were treated with a proteino-polysaccharide compound. The importance of cartilage destruction was evaluated by measuring the articular surfaces and the surface of the fissured areas using an automatic image analyzer; osteophytes were measured by a volumetric study. The percentage of the fissured areas appears to be without correlation with the osteophytosis, the increase of the water content or the decrease of glycosaminoglycans following the procedure. In animals which were treated, the extent of the fissure is significantly reduced but the biochemical and histometric modifications are not too different from those of the reference group.