Comparison of gross and histopathologic findings with quantitative computed tomographic bone density in the distal third metacarpal bone of racehorses.

The research article explores the relationship between bone density determined through quantitative computed tomography (CT) and osteochondral lesions in horses’ metacarpal bones. The study concludes that while subchondral remodeling is associated with the development of such lesions, the correlation between CT density or mean voxel standard deviation and these histopathologic lesions is not strong.

Research Methodology

• The study was carried out on metacarpophalangeal joints obtained from nine racehorses.
• These joints were imaged using computed tomography (CT), and subsequently evaluated for gross damage.
• Sagittal and palmar dorsal plane sections were cut from the distal third metacarpal bone of these horses. These sections were then decalcified and stained with hematoxylin and eosin for further study.
• A score was assigned to microscopic osteochondral lesions and the subchondral remodeling observed in these sections, on a scale of 0-3.
• The ratio of bone volume to tissue volume was also calculated to determine the percent of subchondral bone.
• The researchers then measured the mean quantitative CT density and mean voxel standard deviation using three-dimensional models made from the CT images.

Study Findings

• The study found no association between the mean quantitative CT density and the severity or number of lesions.
• A weak correlation was found between the mean quantitative CT density and the gross score. However, this measure did not prove to be a predictive factor for the gross score.
• There was no correlation found between the mean voxel standard deviation and the gross or histopathologic measures. However, it was found to have a predictive value for mild osteochondral lesions.

Conclusions

• The study concluded that there was not a strong correlation between the mean quantitative CT density or the mean voxel standard deviation, and the histopathologic lesions observed in the distal third metacarpal bone.
• However, an association was found between subchondral remodeling and the development of lesions in the palmar metacarpal.
• These results suggest that while CT scans can provide useful information, they may not be the most accurate tool for predicting the severity or number of osteochondral lesions in horses.