Osteoarthritis (OA) is one of the most frequent musculoskeletal diseases worldwide and is associated with a high burden of disease causing disability and considerable socioeconomic costs. In the USA, 200 000 patients undergo total hip replacement surgery annually as a consequence of joint failure owing to severe OA.1 The pharmacotherapy of advanced OA is limited to symptomatic treatment to obtain pain relief. To date, no drugs are available which allow rebuilding of damaged cartilage,2 and this may not change during the next few years, reinforcing the relevance of targeted interventions in early OA or even before the development of symptoms. As a consequence, clinicians have the challenging task of identifying those …