We propose a Joint Trauma Biomarker Core to oversee all molecular biomarker studies proposed in CORT projects. The Core will provide crucial technical support in the form of validated assays for the OARSI-recommended biomarkers proposed in Projects 2 and 3. In addition, the Core will establish and maintain a comprehensive repository of synovial fluids and sera from animals and patients. This repository will be accessed for advanced biomarker studies predicated on new findings emerging from CORT research. Finally, the Core will foster the development of novel mathematical models of joint injuries for testing functional relationships between biomarkers and joint degeneration. Thus, in addition to assay services the Core will offer resources for testing new biomarker-related hypotheses that flow from CORT discoveries.