Advances in imaging of osteoarthritis and cartilage.

Osteoarthritis (OA) is the most frequent form of arthritis, with major implications for individual and public health care without effective treatment available. The field of joint imaging, and particularly magnetic resonance (MR) imaging, has evolved rapidly owing to technical advances and the application of these to the field of clinical research. Cartilage imaging certainly is at the forefront of these developments. In this review, the different aspects of OA imaging and cartilage assessment, with an emphasis on recent advances, will be presented. The current role of radiography, including advances in the technology for joint space width assessment, will be discussed. The development of various MR imaging techniques capable of facilitating assessment of cartilage morphology and the methods for evaluating the biochemical composition of cartilage will be presented. Advances in quantitative morphologic cartilage assessment and semiquantitative whole-organ assessment will be reviewed. Although MR imaging is the most important modality in imaging of OA and cartilage, others such as ultrasonography play a complementary role that will be discussed briefly.