Platelets are the a component of the blood that helps the clotting process. Since the start of twentieth century, some components have been found in blood to promote the healing of tissues. These specific components include platelet derived growth factor (PDGF) and transforming growth factor beta (TGFß), both of which are contained within the alpha granules of platelets, and fibronectin and vitronetin, which are cell adhesion molecules found in plasma, and fibrin itself.
Platelet Rich Plasma Therapy is a novel therapeutic approach using this knowledge. It has recently begun to gain increasing favor as a way to stimulate the repair of damaged tissue.
How is Platelet Rich Plasma harvested?
A small amount of blood is taken from the periphery (eg, the arm, similar to a blood test) and it is centifuged (rotated at high speeds, through an automated rotating machine). The initial process of centrifugation separates heavier blood cells (including RBC, WBC, and platelets) from lighter plasma and gives us Platelet Rich Plasma (PRP).
Clinical Uses of Platelet Rich Plasma
Platelet-Rich Plasma, by providing the growth factors, helps in faster repair of bone and soft-tissues. In a sense it enriches an enriched medium for growth (as it does not supply cells responsible for healing, but provides biological factors required for the differentiation of mesenchymal stem cells into various specialized cells).
PRP may be clinically applied for wound healing, to provide a jump-start in soft tissue (tendon & ligament) and bone healing. It has also been tried for cases of diabetic ulcer (with the aim of encouraging the growth of new blood vessels).
It has become a possible adjunct in dentistry. PRP enhances the platelet quantity from low level of about 5% in normal blood clot, to enhance healing after surgery in oral and maxillo-facial regions by 2-3 times.
Similar results have been shown in healing of chronic elbow tendinosis, not responsive to conventional treatment.
It may be used in cases of non-healing tendon injuries though results are not always conclusive.
In joint replacement surgeries (for e.g. Total Knee Surgery), PRP has been found to be responsible for shorter periods of hospital stay, less blood loss after surgery, and fewer infections.
PRP is also considered for possible cosmetic purposes.
PRP injections have been found to produce significant improvement in pain of osteoarthritic knee, thought to be due to its cartilage healing effects on the joint.
However, being a relatively new treatment approach, larger clinical trials are needed to establish the efficacy of PRP injections.