title: Post mortem evaluation of palmar osteochondral disease (traumatic osteochondrosis) of the metacarpo/metatarsophalangeal joint in Thoroughbred racehorses.
abstract: BACKGROUND
  Thoroughbred racehorses are commonly affected by subchondral bone injury, but the exact prevalence and the distribution of palmar/plantar osteochondral disease (POD) lesions are unknown. The relationship between pathologies has not been elucidated, although it is widely accepted that POD is a manifestation of traumatic overload arthrosis.
  
  
  OBJECTIVE
  There is an association between grade of POD and other pathologies affecting the third metacarpal and metatarsal (MC/MTIII) condyles (wear lines, cartilage loss, marginal remodelling, dorsal impact injuries and linear fissures).
  
  
  OBJECTIVE
  To evaluate the pathology found affecting the distal MC/MTIII condyles of Thoroughbred racehorses at post mortem examination, to describe the prevalence and distribution of POD lesions within a population of racing Thoroughbreds and to determine relationships between pathologies of the distal condyles of the third metacarpal and metatarsal bones.
  
  
  METHODS
  The metacarpo/metatarsophalangeal joints of 64 Thoroughbred racehorses were examined at routine post mortem examination and graded for third metacarpal and metatarsal condylar pathology. Associations between pathologies were determined.
  
  
  RESULTS
  POD had a within horse prevalence of 67%. There was a significant linear relationship between grade of POD and grades of wear lines, cartilage ulceration and dorsal impact injuries. There was a significant relationship, but this was not linear, between grade of POD and grade of linear fissures. Using ordinal logistic regression, compared to condyles with grade 0 or grade 2 linear fissures, condyles with grade 1 linear fissures were found to be more likely to have a lower POD grade.
  
  
  CONCLUSIONS
  POD can be considered to be a manifestation of traumatic overload arthrosis, but the role of subchondral bone adaptation is complex and warrants further investigation.
authors: Division of Veterinary Clinical Science, University of Liverpool, Leahurst, Neston, Cheshire, UK.
authors: E D
authors: ED
authors: Barr
authors: G L
authors: GL
authors: Pinchbeck
authors: P D
authors: PD
authors: Clegg
authors: A
authors: A
authors: Boyde
authors: C M
authors: CM
authors: Riggs
mesh_terms: D000818:Animals; D018409:Foot Injuries / Q000473:pathology / Q000662:veterinary*; D006734:Horse Diseases / Q000473:pathology*; D006736:Horses; D008297:Male; D055034:Osteochondrosis / Q000473:pathology / Q000662:veterinary*