title: Development of a new biomechanically defined single impact rabbit cartilage trauma model for in vivo-studies.
abstract: BACKGROUND
  Clinically oriented and easy to handle animal models are urgently needed to test pharmacologic treatment of cartilage trauma to reduce the resulting tissue damage by chondrocyte apoptosis and induction of matrix-degrading enzymes.
  
  
  OBJECTIVE
  To develop a biomechanically defined cartilage trauma model.
  
  
  METHODS
  We constructed a novel trauma device that allows biomechanically defined force application to the load-bearing region of the medial and lateral femoral condyles in adult rabbits. The fixation to the femur was specially designed to avoid uncontrolled influx of blood into the joint. The device was tested on the articular femoral surface of cadaveric rabbits.
  
  
  RESULTS
  At a lower energy (1.0 J), the tests showed that superficial and partially deep fissuring, partial necrosis of the chondrocytes, and early proteoglycan loss occurred at the region of impact. Subchondral fractures could be excluded by micro CT. At higher energy (≥ 1.4 J), we observed more pronounced deep fissuring and in some cases complete shearing of the articular cartilage from the subchondral bone.
  
  
  CONCLUSIONS
  Our model represents an easy to use method to create a biomechanically defined cartilage trauma and offers some advantages with respect to handling under aseptic surgical conditions and prevention of uncontrolled intra-articular bleeding from the bone marrow compartment for pharmacologic studies.
authors.affiliation: Department of Orthopaedic Surgery, University of Ulm,   Ulm,   Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Leucht
authors.forename: Lutz
authors.initials: L
authors.lastname: Dürselen
authors.forename: Cathrin
authors.initials: C
authors.lastname: Hogrefe
authors.forename: Helga
authors.initials: H
authors.lastname: Joos
authors.forename: Heiko
authors.initials: H
authors.lastname: Reichel
authors.forename: Herbert
authors.initials: H
authors.lastname: Schmitt
authors.forename: Anita
authors.initials: A
authors.lastname: Ignatius
authors.forename: Rolf E
authors.initials: RE
authors.lastname: Brenner
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D002358:Cartilage, Articular / Q000293:injuries* / Q000601:surgery; D005269:Femur / Q000293:injuries; D011817:Rabbits