Platelet Rich Plasma (PRP) has been used since the 1970’s. The last decade has seen tremendous focus on PRP applications in musculoskeletal medicine. The potential for PRP to promote tissue healing following injury or disease is attractive to many physicians, researchers, and patients alike. Unlike medications or cortisone injections which suppress or mask the underlying problem, PRP shows the potential to heal. The risk of disease transmission is limited since PRP is derived directly from a patient’s own blood. On the flip side, there is significant variability in PRP concentrations from one patient to another. This combined with different methods of preparing PRP, timing, and the selection of activating agents all present challenges in studying and standardizing treatment protocols.
Published studies of PRP use in adults and in animal models have shown promise for a number of orthopedic related conditions. This is especially the case for tendon and soft tissue injuries. The specific mechanism of how PRP works remains elusive, but several well controlled studies have shown positive outcomes with no significant adverse events.
In simplest form, when an injury occurs, the body’s own platelets release co-factors that stimulate recruitment of mesenchymal stem cells (MSCs) to the site of injury. Additionally, inflammation is reduced during this cascade of events and healing is promoted. Some of the known components of PRP included platelet-derived growth factors, insulin-like growth factor, transforming growth factor-beta, fibroblast growth factor-2. Each of these have differing functions in the healing and reparative process.
To date, many professional athletes have been treated with PRP injections. Success rates that appear in the published literature and across the web vary considerably. Some are reported at greater than 90%. Caution must be exercised in interpreting these results as outcome measures vary. Again it is very difficult to compare studies or even one individual versus another due to the issues described above.
We are just beginning to understand how PRP can be used and how effective it can be in the treatment of certain orthopedic conditions.