[Chondropenia: early-stage degenerative disease]

Chondropenia is defined as loss of the articular cartilage volume. It is the early stage of degenerative joint disease. Risk factors include advanced age, obesity, overuse (activity-related injury), menopause, and trauma. Early detection of chondropenia is important with regard to recognition of its causes and assessment of the efficacy of treatment. Magnetic resonance imaging is the most potential tool for noninvasive assessment of articular cartilage. Arthroscopy provides information about the size, surface features, and anatomic localization of cartilage lesions, and the features of the adjacent cartilage. By arthroscopy, tissue thickness and in vivo volume of the cartilage can be measured. Studies have given weight to mechano-acoustic diagnosis and optical tools (optical coherence tomography, reflectance spectroscopy). These studies are based on the relationship between the structural and mechanical features of the cartilage. Determination of breakdown products of cartilage is another potentially important method for assessment.