Successful treatment of persistent dorsal displacement of the soft palate and evaluation of laryngohyoid position in 15 racehorses.
Authors: Ortved K F, Cheetham J, Mitchell L M, Ducharme N G
Journal: Equine veterinary journal
Summary
# Editorial Summary: Laryngeal Tie-Forward for Persistent Dorsal Displacement of the Soft Palate Persistent dorsal displacement of the soft palate (DDSP) differs mechanically from its intermittent counterpart, with evidence suggesting abnormal laryngohyoid positioning—particularly caudal laryngeal descent—may underlie the condition by disrupting the epiglottis-soft palate seal. This retrospective analysis of 15 racehorses treated between 2002 and 2007 compared laryngohyoid anatomy in persistent DDSP cases against age, sex and breed-matched controls with intermittent DDSP, using radiographic measurements to quantify positional differences before and after surgical intervention. Horses with persistent DDSP exhibited significantly more caudal laryngeal positioning (13 mm difference), more caudal and dorsal basihyoid bone placement (10 mm and 7 mm respectively), and more dorsal thyrohyoid-thyroid articulation (10 mm), all supporting the mechanistic theory of laryngeal descent in this syndrome. Thirteen of the 15 horses returned to racing following laryngeal tie-forward alone (7 cases) or combined with laser staphylectomy (8 cases), demonstrating that surgical repositioning of laryngeal anatomy can successfully restore athletic function. For practitioners managing racehorses with persistent DDSP refractory to conservative management, these findings validate laryngeal tie-forward as an effective surgical option with strong return-to-racing potential, particularly when anatomical compromise is identified radiographically.
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Practical Takeaways
- •Laryngeal tie-forward surgery is an effective treatment for persistent DDSP in racehorses, with 87% successfully returning to racing; some cases benefit from additional laser staphylectomy
- •Radiographic evaluation of laryngohyoid position can help differentiate persistent from intermittent DDSP and may guide treatment selection
- •The anatomical differences in laryngeal position between persistent and intermittent DDSP suggest different underlying pathophysiology and support the caudal laryngeal descent hypothesis
Key Findings
- •13 of 15 racehorses with persistent DDSP returned to racing after laryngeal tie-forward surgery, with or without laser staphylectomy
- •Horses with persistent DDSP had a significantly more caudal larynx (13 mm difference, P=0.014) compared to intermittent DDSP horses
- •Persistent DDSP horses demonstrated more caudal (10 mm, P=0.044) and dorsal (7 mm, P=0.01) basihyoid bone positioning than intermittent DDSP horses
- •More dorsal thyrohyoid-thyroid articulation was found in persistent DDSP horses (10 mm difference, P=0.002)