This review presents some new pathogenetic aspects of osteoarthritis. Osteoarthritis has been thought of as a primary disease of cartilage. Studies over the past several years, however, háve shown that articular cartilage is a secondary "victim" of pathological changes in other articular and extra-articular tissues whichaffect the biomechanics and integrity of the cartilage. These tissues include subchondral bone, articular ligaments, periarticular muscles, menisci, sensory nerve endings and synovitis. Obesity plays an important role,not only through its mechanobiological effects, but also through the production of certain mediators by adipose tissue, which affect catabolic and anabolic processes in cartilage.

        Key words: osteoarthritis, pathogenesis, role of articular and extra-articular tissues