Bony fragments in the tarsocrural and metacarpo- or metatarsophalangeal joints in the standardbred horse–a radiographic survey.

The research article investigates the occurrence of osteochondrosis and other bony abnormalities in the joints of Standardbred horses, mostly younger than three years old. The study finds no correlation between these conditions and the gender or side of the horse.

Survey and Findings

• This study conducted a radiographic examination of the tarsocrural (ankle), metacarpophalangeal (knuckle), and metatarsophalangeal joints in 139 Standardbred horses, most of which were under three years old and without any known orthopedic issues.
• Osteochondrosis, a joint disorder where cartilage and bone in the joints degenerate, was found in 18.1 percent of the horses’ tarsocrural joint, with more than half of these showing signs of the condition in both joints.
• The metatarsophalangeal joint presented with single or multiple bony fragments or defects at the plantar proximal end of the proximal phalanx in 28.8 percent of the horses. This suggests joint degeneration or injury.
• The defects were more common in the hind limbs than the forelimbs, and more frequently occurred in the medial (inner) part of the joint than the lateral (outer) part.

Correlations and Incidences

• No significant difference was found in the occurrence of osteochondrosis in the tarsocrural joint and bony fragments in the metacarpo- or metatarsophalangeal joints between male and female horses or between the left and right sides.
• Also, the study found no association between osteochondrosis in the tarsocrural joints and the presence of bony fragments in the plantar part of the metatarsophalangeal joints. This means these two conditions occur independently of each other.
• There were minor instances of bony fragments in the dorsal parts of the metacarpophalangeal and metatarsophalangeal joints, at 2.9 and 2.2 percent respectively.

Overall Affection

• When all the joints were examined, 44.1 percent of the horses showed evidence of osteochondrosis, bony fragments, or defects in the underlying bones in one or more joints. This highlights a significant proportion of Standardbred horses suffering from bone or joint abnormalities.