Successful treatment of persistent dorsal displacement of the soft palate and evaluation of laryngohyoid position in 15 racehorses.

The research investigated the treatment of persistent dorsal displacement of the soft palate (DDSP), a condition in racehorses, by evaluating the laryngohyoid position and the effectiveness of a laryngeal tie-forward surgical procedure. The results suggested that horses with persistent DDSP have different laryngohyoid positions and can be successfully treated with this method.

Study Objective and Methodology

• The study aimed to compare the laryngohyoid positions in horses with persistent DDSP versus those with intermittent DDSP, and evaluate how this might affect treatment efficacy.
• The researchers hypothesized that horses with persistent DDSP may have a different laryngohyoid position, and that a surgical procedure called laryngeal tie-forward could allow these horses to return successfully to racing.
• The study was conducted by reviewing the medical records of 15 racehorses diagnosed with persistent DDSP between 2002 and 2007. Horses diagnosed with intermittent DDSP, matched by age, sex, and breed, were used as a comparison group.

Treatment Procedure and Assessment

• All horses were treated with a laryngeal tie-forward procedure. Additionally, 8 out of the 15 horses with persistent DDSP were also treated with a laser staphylectomy.
• To measure the surgical effect, the researchers compared the laryngohyoid positions pre- and post-operation using a radiographic reference system.
• The outcome of the treatment was assessed by the horses’ return to racing and comparison of pre- and post-operation race earnings.

Key Findings

• The study found a significant correlation between persistent DDSP and certain laryngohyoid positions. Horses with persistent DDSP had a more caudal larynx, a more caudal and dorsal basihyoid bone, and a more dorsal thyrohyoid-thyroid articulation than horses with intermittent DDSP.
• Out of 15 horses with persistent DDSP, 13 were able to return to racing after treatment. This suggests that the laryngeal tie-forward treatment, either on its own or combined with a laser staphylectomy, can successfully treat horses with persistent DDSP.

Conclusions

• The study concluded that horses with persistent DDSP can be successfully treated using laryngeal tie-forward procedure alone or combined with a laser staphylectomy.
• These findings contribute to the understanding of DDSP in horses, highlighting the variations in laryngohyoid positions between horses with persistent DDSP and those with intermittent DDSP.