Anatomical variation of the spinous and transverse processes in the caudal cervical vertebrae and the first thoracic vertebra in horses.

The research discusses the varying anatomical differences in the lower cervical spine and first thoracic vertebra of horses, highlighting breed and sex-related disparities. The study aimed to improve understanding to prevent misdiagnoses.

Research Methodology

In order to draw conclusions about the variation in the anatomy of the horse spinal processes, the study was primarily performed based on:

• Using radiographs of the cervical spine of 270 horses from different breeds and sexes. These were retrospectively examined to identify and categorize anatomical variations.
• Applying statistical analyses, Chi-square tests, or Fisher’s exact test where appropriate, to locate any relationships between radiographic findings and the sex or breed of the horses.
• Performing residual analysis to identify any differences.
• Using Chi-square tests and φ coefficient calculations to determine associations between different types of radiological variation.

Research Findings

The research findings evidenced the complexity of anatomical variations in the horse spine:

• Three different configurations were observed in the spinous process of the 7th cervical vertebra, and two variants were detected in the spinous process of the first thoracic vertebra.
• The presence of the spinous process in the 7th cervical vertebra was directly linked to the breed of the horse.
• Transposition of the ventral process of the 6th cervical vertebra onto the ventral area of the 7th cervical vertebra was found to be associated with the sex of the horse.
• The shape of the first thoracic vertebra’s spinous process displayed a connection with the shape of the 7th cervical vertebra’s spinous process and the appearance of transposition of the ventral process of the 6th cervical vertebra onto the ventral aspect of the 7th.

Conclusion

In summary, the study shows a broad variety of anatomical variations can be detected via radiography in the lower cervical area of the horse. Some configurations even exhibit a higher frequency, depending on the horse’s sex and breed. A clear understanding of these variations is essential to circumvent potential misdiagnoses of periarticular new bone formation. Moreover, it was found that the spinous process of the first thoracic vertebra has two distinct morphological variations.