title: Which cartilage is regenerated, hyaline cartilage or fibrocartilage? Non-invasive ultrasonic evaluation of tissue-engineered cartilage.
abstract: OBJECTIVE
  To investigate ultrasonic evaluation methods for detecting whether the repair tissue is hyaline cartilage or fibrocartilage in new cartilage regeneration therapy.
  
  
  METHODS
  We examined four experimental rabbit models: a spontaneous repair model (group S), a large cartilage defect model (group L), a periosteal graft model (group P) and a tissue-engineered cartilage regeneration model (group T). From the resulting ultrasonic evaluation, we used %MM (the maximum magnitude of the measurement area divided by that of the intact cartilage) as a quantitative index of cartilage regeneration. The results of the ultrasonic evaluation were compared with the histological findings and histological score.
  
  
  RESULTS
  The %MM values were 61.1 +/- 16.5% in group S, 29.8 +/- 15.1% in group L, 36.3 +/- 18.3% in group P and 76.5 +/- 18.7% in group T. The results showed a strong similarity to the histological scoring.
  
  
  CONCLUSIONS
  The ultrasonic examination showed that all the hyaline-like cartilage in groups S and T had a high %MM (more than 60%). Therefore, we could define the borderline between the two types of regenerated cartilage by the %MM.
authors.affiliation: Department of Orthopaedic Surgery, Nara Medical University, 840, Shijyo-cho, Kashihara, Nara, 634-8522, Japan. hattori@naramed-u.ac.jp
authors.forename: K
authors.initials: K
authors.lastname: Hattori
authors.forename: Y
authors.initials: Y
authors.lastname: Takakura
authors.forename: H
authors.initials: H
authors.lastname: Ohgushi
authors.forename: T
authors.initials: T
authors.lastname: Habata
authors.forename: K
authors.initials: K
authors.lastname: Uematsu
authors.forename: M
authors.initials: M
authors.lastname: Takenaka
authors.forename: K
authors.initials: K
authors.lastname: Ikeuchi
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000293:injuries / Q000503:physiopathology / Q000648:ultrastructure*; D002478:Cells, Cultured; D020219:Chondrogenesis / Q000502:physiology; D006614:Hindlimb; D006818:Hyalin; D023421:Models, Animal; D011817:Rabbits; D012038:Regeneration / Q000502:physiology*; D023822:Tissue Engineering / Q000379:methods*; D019737:Transplants; D014945:Wound Healing / Q000502:physiology