Scratching the surface: articular cartilage disorders in the knee.

Powerful techniques with MR imaging are being developed for evaluating articular cartilage. Pharmaceutical and biotechnology development is driven largely by the search for novel therapeutic solutions to the growing problem of arthritis in our aging society. Accordingly, imaging tools that will be used to direct patients to specific therapies and then to monitor treatment effectiveness and safety presently are being refined and validated in rigorous multicenter and multinational clinical trials aimed at gaining regulatory approval. As trials approach completion, radiologists can anticipate an increased demand for expertise and experience in evaluating articular cartilage disorders. This article reviews this novel mechanism for evolving imaging techniques for clinical use through clinical drug trials, lists the most promising MR imaging markers available for evaluating cartilage integrity, and speculates on how these techniques will find their way into clinical practice.