Growth Factor Delivery Methods in the Management of Sports Injuries:The State of Play

In recent years there have been rapid developments in the use of growth factors for accelerated healing of injury. Growth factors have been used in Maxillo-facial and Plastic Surgery with success and the technology is now being developed for Orthopaedics and Sports Medicine applications. Growth factors mediate the biological processes necessary for repair of soft tissues such has muscle, tendon and ligament following acute traumatic, or overuse injury, and animal studies have demonstrated clear benefits in terms of accelerated healing. There are various ways of delivering higher doses of growth factors to injured tissue, but each has in common, a reliance on release of growth factors from blood platelets. Platelets contain growth factors in their á-granules (IGF-1, bFGF, PDGF, EGF, VEGF, TGF-â1) and these are released upon injection at the site of an injury. Three commonly utilised techniques are known as Platelet-rich plasma, autologous blood injections, and autologous conditioned serum. Each of these techniques have been studied clinically in humans to a very limited degree so far, but results are promising in terms of earlier return to play following muscle and particularly tendon injury. The use of growth factors in Sports Medicine is restricted under the terms of the WADA anti-doping code, particularly because of concerns regarding the IGF-1 content of such preparations, and the potential for abuse as performance-enhancing agents. We review the basic science and clinical trials related to the technology, and discuss the use of such agents in relation to the WADA code.