Investigations into the role of the thyrohyoid muscles in the pathogenesis of dorsal displacement of the soft palate in horses.
- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
The research focused on the role of the thyrohyoid muscles in horses and their potential relation to a condition called dorsal displacement of the soft palate, occurring during exercise. The intent was to gather data for improving the management of this condition by surmising that restoring the function of the thyrohyoid muscles could alleviate the issue.
Objectives and Methods
In their study, the researchers assumed that the thyrohyoid (TH) muscles are crucial for the stability of the laryngo-palatal relationship. The dysfunction of these muscles, they proposed, leads to dorsal displacement of the soft palate (DDSP) during exercise in horses. To test this hypothesis, they subjected ten horses to exercise on a high-speed treadmill in four separate treatment conditions:
- Control conditions: Where no treatment was implemented.
- After resection of thyrohyoid muscles: The TH muscles were surgically removed.
- After sham-treatment: A fake treatment meant to mimic the actual treatment.
- After prosthesis-treatment: The function of the TH muscles was restored with surgical sutures.
During these trials, the researchers inspected the upper airway using videoendoscopy, recorded gait frequencies, and measured pharyngeal and tracheal static pressures.
Findings
The study showed that none of the ten horses developed DDSP during two separate treadmill exercise trials under control conditions. However, seven out of ten horses developed DDSP after their TH muscles were resected. After sham-treatment, four of the five horses continued to experience DDSP, but after prosthesis-treatment, where the function of the TH muscles was restored with surgical sutures, five out of six horses no longer experienced DDSP during exercise. The researchers also identified significant irregularities in airway pressures, respiratory frequency, and occurrence of DDSP in both the TH resection and sham-treatment conditions compared to the control conditions. Conversely, no statistical differences were found in any of the parameters measured between the prosthesis-treatment and control conditions.
Conclusions
Consequently, the researchers concluded that the TH muscles’ function plays a crucial role in the stability of the laryngo-palatal relationship and influences the pathophysiology of exercise-induced DDSP in horses. Thus, restoring the function of TH muscles could potentially improve the management of horses with DDSP. To that effect, the study contributes significantly to the understanding of the pathogenesis and management of dorsal displacement of the soft palate in horses, by emphasizing the role of the thyrohyoid muscles.
Cite This Article
Publication
Researcher Affiliations
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York 14853, USA.
MeSH Terms
- Animals
- Endoscopy / veterinary
- Epiglottis / physiopathology
- Exercise Test / veterinary
- Female
- Gait
- Horse Diseases / etiology
- Horse Diseases / physiopathology
- Horse Diseases / surgery
- Horses
- Laryngeal Muscles / physiopathology
- Laryngeal Muscles / surgery
- Male
- Palatal Muscles / physiopathology
- Palatal Muscles / surgery
- Palate, Soft / physiopathology
- Physical Conditioning, Animal
- Random Allocation
Citations
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