title: In Vivo Evaluation of Different Surgical Procedures for Autologous Chondrocyte Implantation.
abstract: OBJECTIVE
  Autologous chondrocyte implantation (ACI) involves the application of a chondrocyte suspension into a membrane-sealed cartilage defect. Recently, "cell-seeded collagen matrix-supported" ACI has been developed wherein chondrocytes are seeded on a biomembrane. This study aimed at preclinically comparing 4 variant ACI techniques in a refined goat model: 2 traditional procedures, whereby the defect is sealed by a periosteal flap or collagen membrane, and 2 cell-seeding methods, with the collagen membrane either sutured or glued into the defect.
  
  
  METHODS
  The efficacy of the surgical techniques was evaluated in an acute critical size chondral defect in the medial condyle of 32 skeletally mature goats, randomly assigned to 1 of the 4 aforementioned treatment groups. After 10 weeks in vivo, the quality of the repair was graded histologically by 2 independent, blinded readers using the "modified O'Driscoll" score.
  
  
  RESULTS
  The cell-seeding procedure whereby the membrane is sutured into the defect has a similar structural repair capacity than traditional ACI techniques. However, when the cell-seeded membrane was glued into the defect, the outcome appeared inferior.
  
  
  CONCLUSIONS
  These findings indicate that optimizing the goat model and the postoperative recovery does allow preclinical evaluation of ACI-based cartilage implants in a load-bearing setting. This preclinical observation provides support to the clinical utilization of the sutured membrane-seeded (ACI-CS) technique, provided sutures, but not fibrin sealants, are used to fix the cell-seeded membrane in the defect bed.
authors.affiliation: TiGenix, Leuven, Belgium ; Present address: Division of Skeletal Tissue Engineering (Prometheus), KU Leuven, Leuven, Belgium.
authors.forename: Marina
authors.initials: M
authors.lastname: Maréchal
authors.affiliation: Medanex Clinic, Diest, Belgium.
authors.forename: Hadewych
authors.initials: H
authors.lastname: Van Hauwermeiren
authors.affiliation: TiGenix, Leuven, Belgium.
authors.forename: Johan
authors.initials: J
authors.lastname: Neys
authors.affiliation: TiGenix, Leuven, Belgium.
authors.forename: Gert
authors.initials: G
authors.lastname: Vanderlinden
authors.affiliation: TiGenix, Leuven, Belgium.
authors.forename: Tom
authors.initials: T
authors.lastname: Van de Putte
keywords: ACI; ACT-CS; O’Driscoll; goat; membrane seeded