Ultrasonographic examination of the equine sacroiliac region.

The research study is focused on defining the normal ultrasonographic appearance of the sacroiliac region (the area where the spine meets the pelvis) in horses, with the aim to improve diagnosis of sacroiliac diseases.

Overview of the Study

• The researchers acknowledged the limited information available on the normal ultrasonographic appearance of horses’ sacroiliac region, emphasizing that understanding its standard structure is crucial for identifying potential pathological changes.
• The study sought to establish clinically relevant reference parameters of the soft tissues and bony structures in this region.
• A total of thirteen cadaver samples and thirteen healthy horses were examined using specific ultrasound imaging protocols to ensure consistency of data.

Methodology

• For the examination, a transcutaneous approach was used primarily, which involved imaging through the skin above the sacral tuberosity (bony protrusions on the sacrum).
• Two key structures were focused upon: the dorsal sacroiliac ligament (a thick band of tissue connecting the sacrum and the ilium bones of the pelvis) and the tendon of the longissimus dorsi muscle (one of the longest muscles in a horse’s body).
• A rectal approach was also employed to properly outline the sacroiliac joint and its neighboring structures.
• These procedures were followed for both the cadaver samples and the live horses without any history of back pain.

Results

• The study found that the tendon of the longissimus dorsi muscle could be clearly distinguished from the dorsal sacroiliac ligament in longitudinal images.
• The transrectal examination of the sacroiliac joint involved an assessment of the bony surfaces of the sacrum and the ilium and a comparison with the contralateral (opposite) side.
• The data showed that ultrasonographic examination offered clear images of the area at the back and at the lower end of the sacroiliac joint, including its adjacent structures, making it an effective tool for diagnosing potential diseases or lesions in this region.

Conclusion

• The research concluded that ultrasonography is an effective tool for examining and differentiating the longissimus dorsi muscle and the dorsal sacroiliac ligament at the level of the sacral tuberosity.
• The reference parameters established through this study may be helpful for veterinary practitioners in diagnosing sacroiliac diseases more accurately.