Osteoarthritis (OA) is the most common type of arthritis in humans and animals. It is a major cause of pain and disability and has significant consequences for public health. The burden of OA is expected to increase with ageing of the population and the present obesity epidemic. Therefore, there is an acute need for reliable biomarkers that can facilitate earlier diagnosis of OA, and inform the prognosis, monitoring and therapeutic strategies for chronic forms of this disease. However, the field is hampered by a lack of reliable, quantifiable, easily measured biomarkers that provide an earlier diagnosis of OA, inform on the prognostic of the disease and monitor and predict the responses of a patient to a therapeutic modality. Biomarkers of tissue turnover in joints have the capacity to reflect disease relevant biological activity and provide information that may be useful diagnostically and therapeutically, potentially enabling a more rational and personalised approach to healthcare management. In this paper, we review recent progress in the area of OA biochemical marker research. We hope that this review stimulates further research into OA biomarkers and contributes to the development of new and innovative tests for early disease diagnosis, facilitating individualised treatment and improving clinical outcome. We also review a selected number of recent patents relevant to the area of OA biomarkers highlighting areas for commercial development.