Platelet-rich therapies in the treatment of orthopaedic sport injuries.

Biomedical sciences have made major advances in understanding how tissues repair, and the signalling mechanisms required to achieve this goal are progressively being dissected. Advances in the understanding of tissue repair mechanisms and the pivotal role of growth factors have stimulated the use of platelet-rich therapies by orthopaedic surgeons and sports physicians, mainly with the aim of stimulating and enhancing tissue healing. Autologous activated platelets retained in fibrin matrices are used as a source of molecular signals that control cell fate, including cell growth, cell differentiation and the synthesis of diverse functional proteins. Thus far, platelet-rich technologies have spawned additional ambitious endeavours, including surgical and non-surgical treatments in sports orthopaedics. Reconstruction of anterior cruciate ligament and tendon surgery and treatment of joint injuries, tendinopathy or muscle tears are but a few examples of the potential applications of this technology in the field of orthopaedic sports medicine. In the present article, some of the most important therapeutic applications using these approaches - especially preparation rich in growth factor (PRGF) technology - are presented, as are some of the limitations, anti-doping concerns and future challenges in the field. In view of a general state of confusion, the concept of platelet-rich plasma needs rigorous definition associated with well characterized products and re-administration procedures. There is evidence that reconstruction of anterior cruciate ligament and tendon surgery combined with PRGF enhances healing and functional recovery; clinical evidence is also appearing in the literature regarding treatment of tendinopathies and osteoarthritis. Currently, the challenge lies in conducting randomized, controlled clinical trials to determine the essential qualities of these technologies. If anti-doping agencies clarify their regulatory guidelines, robust studies in athletes are expected to emerge. Although much research work lies ahead, the current knowledge points to a future in which platelet-rich therapies will continue improving existing conventional approaches to treatment of sports injuries.