title: Platelet-rich plasma in the treatment of skeletal muscle injuries.
abstract: BACKGROUND
  Every year recreational and professional sports cause thousands of lesions to muscle, ligament and tendon. Critical progress in biological interventions could meet a pressing health need to help athletes resume their activity levels.
  
  
  METHODS
  We perform a narrative review on platelet-rich plasma (PRP) therapies and muscle injuries. The field is eminently translational, thus besides clinical data we summarize experimental studies that bring meaningful biological insights on PRP effects. Some concepts regarding healing mechanisms are reviewed including innate immune response, myogenesis and fibrosis. It is commonly thought that PRPs are not uniform and cannot be assessed against each other, thus current PRP classifications are addressed. PRP effects also depend on the characteristics of the host tissue; therefore we focus on clinical muscle injury classifications. Controversial clinical findings are attributed to both the variability in PRP formulations and variability in the application protocols, so we discuss current clinical data in this basis.
  
  
  CONCLUSIONS
  Currently, there is little clinical evidence to support the use of PRP in skeletal muscle injuries. The future of PRP therapies relies not only in finding the best products, most appropriate indications and application protocols, but also in conceiving combination products. Moreover, as our understanding of healing mechanisms progresses, off-the-shelf allogenic PRP products could be part of the solution for sport injuries.
authors.affiliation: Cruces University Hospital, BioCruces Health Research Institute, Regenerative Medicine Laboratory , Barakaldo 48903 , Spain iandia2010@hotmail.com.
authors.forename: Isabel
authors.initials: I
authors.lastname: Andia
authors.forename: Michele
authors.initials: M
authors.lastname: Abate
mesh_terms: D002454:Cell Differentiation; D002986:Clinical Trials as Topic; D005355:Fibrosis / Q000473:pathology; D006801:Humans; D024510:Muscle Development; D018482:Muscle, Skeletal / Q000293:injuries*; D053657:Platelet-Rich Plasma; D017695:Soft Tissue Injuries / Q000628:therapy*; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism; D014945:Wound Healing / Q000502:physiology
keywords: muscle injuries; platelet-rich plasma; sports; tissue regeneration