Radiographic and clinical survey of degenerative joint disease in the distal tarsal joints in Icelandic horses.

This study investigates the occurrence of degenerative joint disease (DJD) in the distal tarsal joints of a group of Icelandic horses used for riding. The researchers examined various factors related to DJD, including the relationship between clinical signs and radiographic findings. They observed a significant correlation between the age of the horses and the prevalence of DJD, though detected lameness did not exhibit a similar correlation.

Study Methodology

• The researchers worked with 614 Icelandic horses aged between 6 and 12 years.
• Radiographs were taken from three projections for each tarsus of the horses. The tarsus is the cluster of seven bones lying between the lower part of the leg and the hoof in horses.
• Each horse underwent a clinical examination, which included palpating the medial (inner side) part of the distal (farthest) tarsus, and assessing the horse’s hindlimb movements before and after performing a flexion test on the tarsus. The flexion test involves bending the tarsus to evaluate joint performance and possible discomfort in the animal.

Key Findings

• Approximately 30.3% of the horses showed radiographic signs of DJD in their distal tarsal joints.
• The researchers found a strong correlation between the prevalence of DJD and the age of the horses. This indicates that older horses are more likely to show signs of DJD.
• Abnormalities found during palpation and hindlimb lameness before and after the tarsus flexion test were significantly associated with radiographic findings, that is, these clinical signs were common in horses with radiographic signs of DJD.
• Lameness, while often mild and most noticeable following the flexion test, did not show a significant correlation with the age of the horses. This suggests that lameness due to DJD is not necessarily more common in older horses.
• The researchers observed that horse lameness could not be predicted solely based on the details of the radiographic findings. This implies that there might be other factors involved in causing lameness in horses with DJD.

Implications

• The study highlights the prevalence of DJD among Icelandic horses used for riding and identifies the correlation between the disease and age.
• The findings show the need for regular and comprehensive clinical and radiographic evaluation of horses, especially as they age.
• Though lameness was a common symptom in horses with radiographic signs of DJD, it could not be predicted by radiographic findings alone, indicating the complexity of DJD and the need for more extensive research to understand its behavior and consequences.