title: Carpometacarpal osteoarthritis in thirty-three horses.
abstract: OBJECTIVE
  To describe signalment, clinical, and radiographic changes associated with carpometacarpal osteoarthritis (CMC-OA) and to report long-term outcome.
  
  
  METHODS
  Case series.
  
  
  METHODS
  Horses (n=33) with CMC-OA.
  
  
  METHODS
  Medical records (1992-2007) of horses diagnosed with CMC-OA were reviewed and signalment, clinical, and radiographic findings retrieved. Owners were contacted for information on the impact of lameness on intended use, response to treatment, progression of lameness, outcome, and owner satisfaction with response to treatment.
  
  
  RESULTS
  CMC-OA identified in 39 limbs, occurred predominantly in middle-aged and older Quarter Horses and Arabians, and caused severe lameness that prevented normal use. Characteristic swelling was centered over the 2nd metacarpal bone/2nd carpal bone articulation. Radiographic changes consisted of proliferative new bone, narrowed joint space, and subchondral lysis. Of 20 horses with follow-up, 7 of 14 treated horses were euthanatized within 4 years and 4 of 5 nontreated horses within 3 years. Response to treatment was short lived and considered very poor by most owners.
  
  
  CONCLUSIONS
  CMC-OA seemingly occurs primarily in Quarter Horses and Arabians in our region. Response to conservative treatment is very poor and short-lived with most horses being euthanatized.
  
  
  CONCLUSIONS
  Conventional treatment methods are unsuccessful for treating CMC-OA.
authors.affiliation: Department of Large Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada. luca.panizzi@usask.ca
authors.forename: Luca
authors.initials: L
authors.lastname: Panizzi
authors.forename: Spencer M
authors.initials: SM
authors.lastname: Barber
authors.forename: Hayley M
authors.initials: HM
authors.lastname: Lang
authors.forename: James L
authors.initials: JL
authors.lastname: Carmalt
mesh_terms: D000367:Age Factors; D000818:Animals; D018450:Disease Progression; D006734:Horse Diseases / Q000175:diagnosis* / Q000473:pathology; D006736:Horses; D007794:Lameness, Animal / Q000175:diagnosis; D010003:Osteoarthritis / Q000175:diagnosis / Q000473:pathology / Q000662:veterinary*; D011379:Prognosis