PRP Injection Background PRP is derived from your own blood by taking a sample of venous blood, placing it in a special tube, and spinning the blood in a centrifuge. This separates the blood into red blood cells, platelets, and plasma. The middle layer is the PRP, which contains highly concentrated platelets, the cells that promote blood clotting. These include platelet derived growth factor, which interact with the local cells and send signals that initiate division and migration. The basic idea behind PRP injection is to deliver high concentrations of growth factors to an area of injury, with the hope of stimulating a healing response and reducing inflammation in the tissue. Over the past 5 years, PRP has been recognized for its potential in treating both chronic and acute musculoskeletal injuries involving tendons, ligaments, and muscles.