A medical treatment breakthrough. PRP (platelet Rich Plasma) explained.
According to the World Health Organization (WHO), musculoskeletal injuries are the most common cause of severe long-term pain and physical disability, and affect hundreds of millions of people around the world. The impact such injuries have on everyday life is substantial. Thus, the primary aim of orthopaedic surgeons is a safe and full recovery for their patients with a return to pre-injury level of activity as quickly as possible. The traditional management of orthopaedic and sports related injuries includes everything from conservative “RICE” treatment and physical therapy to corticosteroid injections and surgical intervention. Recently, advances in biomedicine and biotechnology have enthused the use of cell therapy, tissue engineering, and autologous blood concentrates to enhance healing and stimulate growth in bone and soft tissue injuries.
One of the most popular methods used to biologically enhance healing in the fields of orthopaedic surgery and sports medicine includes the use of autologous blood products, particularly, platelet rich plasma (PRP). PRP is an autologous concentration of human platelets to supra-physiologic levels. It is produced from a patient’s peripheral vein and centrifuged to achieve a high concentration of platelets within a small volume of plasma. It is then re-injected at a site of injury or inserted as a gel or other biomaterials during surgery.
Historically, platelets have been used to treat patients with thrombocytopenia or hemorrhage. Other blood products such as fibrin (in the form of surgical glue) have been utilized for wound healing. In fact, fibrin (in the form of a clot) has been used in a few studies to augment healing in meniscal repairs and also to augment graft healing in ACL reconstruction. Because of its limited use only for surgical procedures and the inability to modify the platelet concentration, fibrin in its various forms is not as extensively used as PRP for sports related injuries.
PRP therapy has grown in popularity over the past few years. Not only has there been an increasing number of basic science and clinical studies, there has also been a rising level of public awareness secondary to the use of PRP to treat high-profile athletes. In fact, one of the most cited articles to date on PRP therapy was published in the New York Times showcasing its use in two professional athletes
Many clinicians feel that PRP therapy is safe given its autologous nature and long-term usage without any reported major complications. For this reason, in addition to its easy availability, it is readily used in clinical and surgical settings. Despite its widespread unregulated use, the efficacy of PRP therapy has yet to be established. There are many unanswered questions concerning the composition of PRP, individual blood product characteristics, different protocols of production, different methods of administration, and mechanisms of action exerted by PRP and its individual components on a cellular level.
There is a general consensus in PRP research that the injection of concentrated platelets, once activated, results in an exponential increase in numerous growth factors at the sight of injection. However, the function of many growth factors, chemokines, cytokines, and inflammatory mediators has not been elucidated, nor have the interactions between factors and their influence on neighboring cells. As such, the primary purpose of this article is to provide an overview of PRP-mediated effects by discussing current research on growth factors and proposed mechanisms by which PRP exerts its downstream effects on healing muscles, tendons, and ligaments. This review will first address the natural healing process for soft tissue injures; followed by proposed mechanisms of action of PRP and associated growth in tendon and ligament injuries, and muscle contusion. Finally, current and future areas of research will be discussed to address common unanswered questions concerning the application of PRP for sports-related injuries.