title: Influence of platelet time activation on articular cartilage growth in the rabbit knee: preliminary study.
abstract: OBJECTIVE
  The aim of the present article was to study the influence of platelets and different time activation on cartilage growth in articular defects in the rabbit knee.
  
  
  METHODS
  Twelve male New Zealand rabbits (12 weeks) were divided in two groups. Under general anaesthesia, a 4 mm diameter and 2 mm deep defect was performed in medial condyles in both knees. The right knee defect was filled with platelet concentrate 5 min after being activated with ClCa in group A, and 2 min afterwards in group B. Platelets were obtained by centrifuging 10 ml arterial blood from the rabbit prior to the surgical procedure. The left knee defect was not filled. Rabbits were sacrificed 6 weeks after surgery. Macroscopic and microscopic studies were performed.
  
  
  RESULTS
  In group A, hyaline cartilage was observed in the right knee defect at the end of the experiment in five rabbits. None of the defects of the left knees showed hyaline cartilage growth. In group B, hyaline cartilage was observed in the right knee defect in only one rabbit. Nevertheless, in group B, all rabbits presented better chondral cellularity and regeneration and lower fibrosis in defects treated with platelets than in non-treated ones.
  
  
  CONCLUSIONS
  This technique for articular defect reconstruction with platelets is simple and easy, and has shown satisfactory results in our study. Platelets may be useful as an autologous source of multiple growth factors for articular defect reconstruction. Nevertheless, this is a preliminary study and further research is required.
authors.affiliation: Traumatology and Orthopaedic Surgery, Area III, Zaragoza, Spain. fegarcia@comz.org
authors.forename: Felícito
authors.initials: F
authors.lastname: García-Alvarez
authors.forename: Tomás
authors.initials: T
authors.lastname: Castiella
authors.forename: Elena
authors.initials: E
authors.lastname: Guallar
authors.forename: José María
authors.initials: JM
authors.lastname: Grasa
authors.forename: Enrique
authors.initials: E
authors.lastname: Gómez-Barrena
authors.forename: Antonio
authors.initials: A
authors.lastname: Laclériga
mesh_terms: D000818:Animals; D001792:Blood Platelets / Q000187:drug effects / Q000502:physiology*; D002118:Calcium / Q000494:pharmacology; D002358:Cartilage, Articular / Q000187:drug effects / Q000293:injuries* / Q000503:physiopathology*; D007718:Knee Injuries / Q000473:pathology / Q000503:physiopathology* / Q000628:therapy; D008297:Male; D015539:Platelet Activation / Q000187:drug effects / Q000502:physiology*; D011817:Rabbits; D014945:Wound Healing / Q000187:drug effects / Q000502:physiology*
chemical_list: D002118:Calcium