Relevance of osteoproliferation as an outcome parameter in ankylosing spondylitis.

In light of the impressive efficacy of tumor necrosis factor blockers in the treatment of ankylosing spondylitis, particularly in patients with short disease duration, defining outcome parameters to monitor the structural damage of the disease has become more pertinent. In this Viewpoint the authors explore the relevance of osteoproliferation amongst other outcome parameters.