title: Platelet-rich plasma in the conservative treatment of painful tendinopathy: a systematic review and meta-analysis of controlled studies.
abstract: BACKGROUND
  Platelet-rich plasma (PRP) seeks to meet the multifaceted demand of degenerated tendons providing several molecules capable of boosting healing.
  
  
  CONCLUSIONS
  PRP is used for managing tendinopathy, but its efficacy is controversial.
  
  
  METHODS
  Electronic databases were searched for clinical studies assessing PRP efficacy. Methodological quality was evaluated using the methods described in the Cochrane Handbook for systematic reviews.
  
  
  RESULTS
  Thirteen prospective controlled studies, comprising 886 patients and diverse tendons were included; 53.8% of studies used identical PRP protocol.
  
  
  RESULTS
  Sources of heterogeneity included different comparators, outcome scores, follow-up periods and diverse injection protocols, but not PRP formulation per se.
  
  
  CONCLUSIONS
  Pooling pain outcomes over time and across different tendons showed that L-PRP injections ameliorated pain in the intermediate-long term compared with control interventions, weighted mean difference (95% CI): 3 months, -0.61 (-0.97, -0.25); 1 year, -1.56 (-2.27, -0.83). However, these findings cannot be applied to the management of individual patients given low power and precision.
  
  
  METHODS
  Further studies circumventing heterogeneity are needed to reach firm conclusions. Available evidence can help to overcome hurdles to future clinical research and bring forward PRP therapies.
authors.affiliation: Regenerative Medicine Laboratory, BioCruces Health Research Institute, Cruces University Hospital, 48903 Barakaldo, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Andia
authors.affiliation: Primary Care Research Unit of Bizkaia, BioCruces Health Research Institute, Bilbao, Spain.
authors.forename: P M
authors.initials: PM
authors.lastname: Latorre
authors.affiliation: Primary Care Research Unit of Bizkaia, BioCruces Health Research Institute, Bilbao, Spain.
authors.forename: M C
authors.initials: MC
authors.lastname: Gomez
authors.affiliation: Primary Care Research Unit of Bizkaia, BioCruces Health Research Institute, Bilbao, Spain.
authors.forename: N
authors.initials: N
authors.lastname: Burgos-Alonso
authors.affiliation: Department of Medicine and Science of Aging, University G. d'Annunzio, Chieti-Pescara, Chieti Scalo, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Abate
authors.affiliation: Center for Sports and Exercise Medicine, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Mile End Hospital, 275 Bancroft Road, London E1 4DG, UK n.maffulli@qmul.ac.uk.
authors.forename: N
authors.initials: N
authors.lastname: Maffulli
mesh_terms: D015982:Bias; D006801:Humans; D007270:Injections, Intra-Articular / Q000379:methods; D059408:Pain Management / Q000379:methods; D017713:Platelet Transfusion / Q000379:methods; D053657:Platelet-Rich Plasma; D012107:Research Design; D052256:Tendinopathy / Q000628:therapy*; D016896:Treatment Outcome
keywords: clinical trials; conservative management; meta-analysis; pain; platelet-rich plasma; tendinopathy