MR imaging of intra- and periarticular soft tissues and subchondral bone in knee osteoarthritis.

Osteoarthritis of the knee has to be considered a disease of the whole joint. Magnetic resonance imaging allows superior assessment of all joint tissues that may be involved in the disease process, such as the subchondral bone, synovium, ligaments, and periarticular soft tissues. Reliable MR imaging-based scoring systems are available to assess and quantify these structures and associated pathology. Cross-sectional and longitudinal evaluation has enabled us to understand their relevance in explaining pain and structural progression.