Platelet Rich Plasma (PRP)

You might have heard about PRP from friends or read about it in the news. PRP stands for "platelet rich plasma." This is a concentration of platelet cells that are present in the blood and normally assist with blood clotting. Platelets and the liquid plasma of blood contain many factors that are required for healing.


PRPThe first step involves drawing a blood sample from your vein. A tube of this blood is placed in a centrifuge, which is a machine that separates the blood into many components. Platelet rich plasma is collected and treated before it is injected into an area to promote healing.


Several basic science studies in animal models suggest that PRP treatment can improve healing in soft tissue and bone. For example, increased numbers of cells and improved tendon strength have been noted in Achilles tendon injuries (in the ankle) and improved muscle regeneration has been shown in gastrocnemius (calf) muscle injuries. 


These favorable findings in animal models have led to the widespread use of PRP treatment for a variety of conditions, including acute and chronic tendon problems, as well as injuries to ligaments and muscles.  Some early-stage clinical studies in humans have been promising, but are limited by their study design and few patients. 


The most promising early results have been seen when PRP treatment is used for chronic tendon conditions, such as lateral epicondylitis (tennis elbow) and Achilles tendinosis, which impacts the Achilles tendon. Nonetheless, a study in the Journal of the American Medical Association reported that there was no advantage to using PRP injection compared to saline (placebo) injection for the treatment of Achilles tendinosis. 


Other studies have been and continue to be conducted involving knee arthritis, rotator cuff tears, and knee ligament injuries. Overall, there is limited support of PRP treatment in published clinical studies. However, because PRP is created from a patient's own blood, it is considered a relatively low-risk treatment with the potential to improve or speed healing. More studies are needed to prove the effectiveness of PRP treatment and to research the best ways to standardize the treatment's preparation.


Because PRP is given in the hopes of optimizing the initial inflammatory response of healing, anti-inflammatoriy medications should be stopped at the time of PRP treatment. Also, PRP does contain endogenous growth factors, so some agencies consider it to be a performance-enhancing substance. For instance, the World Anti-Doping Agency and the United States Anti-Doping Agency forbid the injection of PRP within muscles because of the possibility that the growth factors could enhance a person's performance. However, there are currently no data to suggest that PRP is actually a performance-enhancing substance. Major professional sports leagues have not yet addressed the topic of PRP.


Key Points to Remember

  • Platelet Rich Plasma (PRP) comes from your own blood.
  • PRP is a concentrated source of growth factors and cellular signaling factors that play a significant role in the biology of healing.
  • Basic science studies show that PRP treatment may improve healing in many tissues.
  • Few clinical studies in humans show the effectiveness of PRP treatment.
  • Anti-inflammatory medicines should be stopped before and after PRP treatment is given.