Biomarkers have been identified in a growing number of pathologic processes. There is a complex interplay of pro-inflammatory and anti-inflammatory bioactive molecules that affects supportive tissue matrix and moderates cellular proliferation, differentiation, migration, and turnover. This modulation of anabolic and catabolic cascades plays a crucial role in degradative and regenerative pathways after injury, and after surgical treatment. These biomarkers are increasingly of interest in the field of medicine, and particularly orthopedic surgery, to better understand articular cartilage abnormalities and the pathophysiology of degenerative and posttraumatic osteoarthritis. Improved knowledge of the role of individual biomarkers, and how they interact, will encourage therapeutic innovation and development, with the goal of altering the natural history of degenerative joint disorders, and an assortment of other pathologic conditions.