title: Development of an equine groove model to induce metacarpophalangeal osteoarthritis: a pilot study on 6 horses.
abstract: The aim of this work was to develop an equine metacarpophalangeal joint model that induces osteoarthritis that is not primarily mediated by instability or inflammation. The study involved six Standardbred horses. Standardized cartilage surface damage or "grooves" were created arthroscopically on the distal dorsal aspect of the lateral and medial metacarpal condyles of a randomly chosen limb. The contralateral limb was sham operated. After 2 weeks of stall rest, horses were trotted 30 minutes every other day for 8 weeks, then evaluated for lameness and radiographed. Synovial fluid was analyzed for cytology and biomarkers. At 10 weeks post-surgery, horses were euthanized for macroscopic and histologic joint evaluation. Arthroscopic grooving allowed precise and identical damage to the cartilage of all animals. Under the controlled exercise regime, this osteoarthritis groove model displayed significant radiographic, macroscopic, and microscopic degenerative and reactive changes. Histology demonstrated consistent surgically induced grooves limited to non-calcified cartilage and accompanied by secondary adjacent cartilage lesions, chondrocyte necrosis, chondrocyte clusters, cartilage matrix softening, fissuring, mild subchondral bone inflammation, edema, and osteoblastic margination. Synovial fluid biochemistry and cytology demonstrated significantly elevated total protein without an increase in prostaglandin E2, neutrophils, or chondrocytes. This equine metacarpophalangeal groove model demonstrated that standardized non-calcified cartilage damage accompanied by exercise triggered altered osteochondral morphology and cartilage degeneration with minimal or inefficient repair and little inflammatory response. This model, if validated, would allow for assessment of disease processes and the effects of therapy.
authors: Equine Research Centre, University of Lyon, VetAgro Sup, Veterinary Campus of Lyon, GREMERES-ICE, Marcy l'Etoile, France.
authors: Ugo
authors: U
authors: Maninchedda
authors: Equine Research Centre, University of Lyon, VetAgro Sup, Veterinary Campus of Lyon, GREMERES-ICE, Marcy l'Etoile, France.
authors: Olivier M
authors: OM
authors: Lepage
authors: Equine Research Centre, University of Lyon, VetAgro Sup, Veterinary Campus of Lyon, GREMERES-ICE, Marcy l'Etoile, France.
authors: Monika
authors: M
authors: Gangl
authors: Exploratory Unit, Sanofi-aventis Recherche, Montpellier, France.
authors: Sandrine
authors: S
authors: Hilairet
authors: Exploratory Unit, Sanofi-aventis Recherche, Montpellier, France.
authors: Bernard
authors: B
authors: Remandet
authors: Exploratory Unit, Sanofi-aventis Recherche, Montpellier, France.
authors: Francoise
authors: F
authors: Meot
authors: Exploratory Unit, Sanofi-aventis Recherche, Montpellier, France.
authors: Geraldine
authors: G
authors: Penarier
authors: Equine Research Centre, University of Lyon, VetAgro Sup, Veterinary Campus of Lyon, GREMERES-ICE, Marcy l'Etoile, France.
authors: Emilie
authors: E
authors: Segard
authors: Exploratory Unit, Sanofi-aventis Recherche, Montpellier, France.
authors: Pierre
authors: P
authors: Cortez
authors: Clinical unit for osteoarticular diseases, CHU Lapeyronie University Hospital, Montpellier, France.
authors: Christian
authors: C
authors: Jorgensen
authors: Exploratory Unit, Sanofi-aventis Recherche, Montpellier, France.
authors: Régis
authors: R
authors: Steinberg
mesh_terms: D000818:Animals; D001182:Arthroscopy; D002358:Cartilage, Articular / Q000000981:diagnostic imaging / Q000473:pathology*; D004195:Disease Models, Animal; D005260:Female; D006736:Horses; D007794:Lameness, Animal; D008297:Male; D008662:Metacarpophalangeal Joint / Q000000981:diagnostic imaging / Q000473:pathology*; D010003:Osteoarthritis / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D010865:Pilot Projects; D011859:Radiography; D013582:Synovial Fluid / Q000000981:diagnostic imaging