title: Platelet-rich plasma (PRP) applied during total knee arthroplasty.
abstract: OBJECTIVE
  To evaluate the efficacy of platelet-rich plasma regarding healing, pain and hemostasis after total knee arthroplasty, by means of a blinded randomized controlled and blinded clinical study.
  
  
  METHODS
  Forty patients who were going to undergo implantation of a total knee prosthesis were selected and randomized. In 20 of these patients, platelet-rich plasma was applied before the joint capsule was closed. The hemoglobin (mg/dL) and hematocrit (%) levels were assayed before the operation and 24 and 48 h afterwards. The Womac questionnaire and a verbal pain scale were applied and knee range of motion measurements were made up to the second postoperative month. The statistical analysis compared the results with the aim of determining whether there were any differences between the groups at each of the evaluation times.
  
  
  RESULTS
  The hemoglobin (mg/dL) and hematocrit (%) measurements made before the operation and 24 and 48 h afterwards did not show any significant differences between the groups (p > 0.05). The Womac questionnaire and the range of motion measured before the operation and up to the first two months also did not show any statistical differences between the groups (p > 0.05). The pain evaluation using the verbal scale showed that there was an advantage for the group that received platelet-rich plasma, 24 h, 48 h, one week, three weeks and two months after the operation (p < 0.05).
  
  
  CONCLUSIONS
  In the manner in which the platelet-rich plasma was used, it was not shown to be effective for reducing bleeding or improving knee function after arthroplasty, in comparison with the controls. There was an advantage on the postoperative verbal pain scale.
authors.affiliation: Uniort.e Orthopedics Hospital, Santa Casa de Londrina, Londrina, PR, Brazil.
authors.forename: João Paulo Fernandes
authors.initials: JP
authors.lastname: Guerreiro
authors.affiliation: Uniort.e Orthopedics Hospital, Santa Casa de Londrina, Londrina, PR, Brazil.
authors.forename: Marcus Vinicius
authors.initials: MV
authors.lastname: Danieli
authors.affiliation: Uniort.e Orthopedics Hospital, Santa Casa de Londrina, Londrina, PR, Brazil.
authors.forename: Alexandre Oliveira
authors.initials: AO
authors.lastname: Queiroz
authors.affiliation: Hemocenter of Botucatu, Faculdade de Medicina de Botucatu (UNESP), Botucatu, SP, Brazil.
authors.forename: Elenice
authors.initials: E
authors.lastname: Deffune
authors.affiliation: Hemocenter of Botucatu, Faculdade de Medicina de Botucatu (UNESP), Botucatu, SP, Brazil.
authors.forename: Rosana Rossi
authors.initials: RR
authors.lastname: Ferreira
keywords: Arthroplasty; Hemorrhage; Knee; Platelet-rich plasma; Transfusion