Imaging of cartilage and osteochondral injuries: a case-based review.

Current high-field magnetic resonance imaging (MRI) techniques provide a sensitive and reliable diagnostic tool for the evaluation of cartilage and osteochondral injury. This article summarizes technical factors for optimal MRI evaluation of articular cartilage of the knee. There is emphasis on the important correlation of the MRI signal to the structure of the type II collagen matrix in normal cartilage, with an understanding that alterations in this signal pattern can be an important sign of cartilage injury. Finally, specific patterns of cartilage injury and application of MRI in evaluating cartilage repair are illustrated through a series of selected cases.