Ex Vivo Computed Tomographic Evaluation of Morphology Variations in Equine Cervical Vertebrae.

This article explores the minor structural differences found via CT scans in the neck vertebrae of horses, aiming to help identify what is normal variation versus signs of spinal disease. These results show the variety in vertebrae structure between individual horses and suggest these changes are not necessarily indicative of spinal problems.

Research Objective and Methodology

• The primary aim of the study is to provide a better understanding of the normal differences in structure and symmetry of the neck and upper spine (cervical and cervicothoracic vertebrae) in horses. This knowledge would help medical professionals interpret diagnostic imaging results more accurately when looking for signs of spinal disease.
• The study involved detailed examinations of CT scans of the necks of horses after their death. These horses did not have any known growth disorders affecting their spines. Both past and newly conducted CT scans were included in the data.
• A total of 78 horses, 27 foals and 51 mature horses, were included in the study.

Study Findings

• Approximately one-third of the horses had a particular structural difference where a part of the sixth cervical vertebra (C6) was shifted towards the seventh (C7). This change was found in both the left and right sides and in both the bilateral and unilateral forms.
• Instances of other abnormalities such as malformations of the joint between the skull and the first vertebra, unusually small first ribs, and extra bits of bone on the first thoracic vertebra were found less frequently.
• These differences in vertebrae structure were technically classified as ‘homeotic’ or ‘transitional’ changes, indicating changes in structure between two types of vertebrae.
• The researchers found no significant differences in the amount of these variations when comparing horses with or without clinical signs of disease or between younger and older horses.

Conclusions

• The findings from this study imply that the most common variation in the structure of equine neck vertebrae involves a shift in a part of C6 towards C7. This is considered as a normal variation rather than a sign of disease.
• Homeotic or transitional variations at the cervicothoracic spine where the neck meets the upper part of the main spine are less common in horses.
• The study reaffirms the importance of understanding the range of normal structural differences in horse vertebrae. This knowledge is crucial for interpreting CT scans accurately and identifying genuine signs of cervical spinal disease.