Autologous Blood Injection (ABPI) involves injecting a patient’s blood into a damaged part of the body. Blood contains many nutrients and substances which are thought to promote healing. Platelets are tiny cells in blood, which stick to each other when we cut ourselves to result in the formation of a clot to stop any further bleeding. Platelets contain many powerful growth factors, in particular Platelet Derived Growth Factor (PDGF), which has been shown to promote healing of many types of tissues, including bone, teeth, skin and the tissue lining our eyes. PDGF also promotes healing of tendons, which are damaged due to excessive use and/or the ageing process.