title: The canine 'groove' model, compared with the ACLT model of osteoarthritis.
abstract: OBJECTIVE
  The frequently used anterior cruciate ligament transection (ACLT) model of osteoarthritis (OA) in the dog, makes use of a permanent trigger (joint instability) for inducing degenerative changes. The present study evaluates a canine model of degenerative cartilage damage, mimicking OA, which is induced without making use of permanent joint instability.
  
  
  METHODS
  The articular cartilage of the weight-bearing areas of the femoral condyles in one knee of ten beagle dogs was damaged by making grooves, without damaging the subchondral bone. Surgery was followed by 10 weeks intensified loading of the affected joint. Subsequently, joint damage and inflammation were evaluated. The effects were compared with those of the ACLT model.
  
  
  RESULTS
  Histological analysis showed chondrocyte clusters around cartilage lesions and moderate loss of proteoglycans in the 'groove' model. Synovial inflammation was mild. Biochemical analysis of cartilage showed changes in matrix proteoglycan turnover, proteoglycan content, and collagen damage, all characteristics of OA. Synovial fluid MMP-1, -3 and -13 activity was enhanced. Changes were found in condyles and plateau, were similar for all animals tested, and were similar to the changes observed in the ACLT model.
  
  
  CONCLUSIONS
  The presently described canine 'groove' model shows characteristics identical to those seen in the ACLT model but differs in a way that the changes are induced without joint instability. The latter is expected to make the 'groove' model more sensitive to treatment.
authors.affiliation: Department of Rheumatology & Clinical Immunology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: A C A
authors.initials: AC
authors.lastname: Marijnissen
authors.forename: P M
authors.initials: PM
authors.lastname: van Roermund
authors.forename: J M
authors.initials: JM
authors.lastname: TeKoppele
authors.forename: J W J
authors.initials: JW
authors.lastname: Bijlsma
authors.forename: F P J G
authors.initials: FP
authors.lastname: Lafeber
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000473:pathology / Q000601:surgery; D019902:Chondrocytes / Q000502:physiology; D003094:Collagen / Q000648:ultrastructure; D017364:Collagenases / Q000378:metabolism; D004285:Dogs; D005260:Female; D020781:Matrix Metalloproteinase 1 / Q000378:metabolism; D053509:Matrix Metalloproteinase 13; D019278:Matrix Metalloproteinase 3 / Q000378:metabolism; D023421:Models, Animal; D010003:Osteoarthritis / Q000473:pathology / Q000503:physiopathology*; D011509:Proteoglycans / Q000502:physiology; D013582:Synovial Fluid / Q000737:chemistry; D016474:Weight-Bearing
chemical_list: D011509:Proteoglycans; D003094:Collagen; D017364:Collagenases; D053509:Matrix Metalloproteinase 13; D019278:Matrix Metalloproteinase 3; D020781:Matrix Metalloproteinase 1