Tendon healing and platelet-rich plasma therapies.

IMPORTANCE OF THE FIELD: The therapeutic use of platelet-rich plasma (PRP) is an autologous biotechnology that relies on the local delivery of a wide range of growth factors and cytokines with the aim of enhancing tissue healing. Understanding both tendon healing and PRP therapies is an area of research that is critically important in developing optimal formulations and protocols to achieve the intended therapeutic effects. AREAS COVERED IN THIS REVIEW: We summarise recent information on the mechanisms inherent to the earliest response to tendon injury. We then describe the positive effect of PRP therapies on tendon healing. Research on tendinopathy has produced several biological hypotheses based on histopathological, biochemical and clinical findings showing that cell apoptosis, angiofibroblastic features or abnormal biochemical adaptations underlie the condition. WHAT THE READER WILL GAIN: The article provides insights into early healing mechanisms and the influence of PRP therapies on inflammation, cell migration, angiogenesis and the proliferation and synthesis of extracellular matrix. The knowledge gained helps to better understand and optimize tendon therapies. TAKE HOME MESSAGE: The use of endogenous therapies has a positive effect on experimental tendon healing. However, several obstacles need to be addressed to optimise medical practice in this field.