In recent years there has been a boom in the use of platelet-rich plasma (PRP) as an orthobiology (therapy based on cell biological agents) material agent. The presence of growth factors and other bioactive agents stored in alpha platelet granules and whose properties are well determined in cell proliferation, angiogenesis and extracellular matrix formation have involved the PRP containing supraphysiological concentrations of autologous platelets in tissue regeneration processes. The relative ease of preparation of PRP, its generally ambulatory application, the almost complete absence of side effects and the possibility to observe satisfactory results of clinical improvement makes the PRP a promising treatment in regenerative processes. However, there is still a lack of knowledge of the mechanism of action of the PRP, creating skepticism regarding their use and potential efficacy. Caution should be taken until the clinical evidence is stablished. On this subject some questions that should be answered in future research are listed below: What is the optimal preparation of PRP? What is the most effective method for the activation of PRP? Which is better, the use of total PRP or only the platelet growth factors? And finally, what pathological conditions should be chosen for the routine application of PRP? The answers to these questions through well-designed studies and systematic reviews by experts, would lead to the routine use of PRP as the recommended treatment. As final conclusion, the AAOS (The American Academy of Orthopaedic Surgeons) made a consideration that today is still valid: in a Forum in 2011 concluded that "the PRP is an option that has not yet been proven."