Platelet Rich Plasma (PRP) Prolotherapy is a method of injection designed to stimulate healing. Platelet rich plasma is defined as autologous blood with concentrations of platelets above baseline levels, which contains at least seven growth factors. Cell ratios in normal blood contain only 6% platelets, however in PRP there is a concentration of 94% platelets. Platelets contain a number of proteins, cytokines and other bioactive factors that initiate and regulate basic aspects of natural wound healing. Circulating platelets secrete growth factors, such as platelet-derived growth factor (stimulates cell replication, angiogenesis), vascular endothelial growth factor (angiogenesis), fibroblast growth factor (proliferation of myoblasts and angiogenesis), and insulin-like growth factor-1 (mediates growth and repair of skeletal muscle), among others. Enhanced healing is possible when platelet concentration is increased with PRP. Activated platelets “signal” to distant repair cells, including adult stem cells, to come to the injury site. Increasing the volume of platelets accordingly increases the subsequent influx of repair and stem cells. Because the concentrated platelets are suspended in a small volume of plasma, the three plasma proteins fibrin, fibronectin, and vitronectin contribute to a repair matrix. You could compare Prolotherapy and PRP this way: Prolotherapy is like planting seeds in a garden; PRP Prolotherapy is planting seeds with fertilizer.