Long-term maintenance of arytenoid cartilage abduction and stability during exercise after laryngoplasty in 33 horses.
Authors: Barnett Timothy P, O'Leary John Mark, Parkin Timothy D H, Dixon Padraic M, Barakzai Safia Z
Journal: Veterinary surgery : VS
Summary
# Editorial Summary: Long-term Arytenoid Abduction Following Laryngoplasty Laryngoplasty is commonly performed to address dorsal displacement of the soft palate and arytenoid cartilage collapse, but whether surgically achieved abduction is maintained during athletic work remains clinically important. This case series examined 33 horses with pre- and post-operative endoscopic data, reassessing arytenoid cartilage position at rest and during over-ground exercise an average of 33 months after surgery. The majority of horses maintained grade 3 abduction long-term, with most deterioration occurring within the first six weeks post-operatively; resting measurements at week 6 proved highly predictive of long-term resting position (ρ = .89, P < .001), whilst early week 1 measurements did not. Paradoxically, arytenoid instability during exercise occurred in only 7 of 33 horses and bore no significant relationship to either the resting abduction grade or the magnitude of postoperative abductory loss, suggesting that dynamic stability depends on factors beyond static anatomical positioning alone. These findings have important implications for post-operative management and prognostication: week 6 resting endoscopy appears a more reliable indicator of long-term surgical success than immediate post-operative assessment, yet clinicians should recognise that satisfactory resting abduction does not guarantee stable arytenoid function during exercise, and that some horses with good surgical outcomes may still demonstrate dynamic airway collapse under work conditions.
Read the full abstract on PubMed
Practical Takeaways
- •Week 6 postoperative endoscopic assessment is more predictive of long-term laryngoplasty outcome than week 1 assessment; use week 6 findings for prognostication rather than early postoperative grades
- •Resting arytenoid abduction grade does not reliably predict stability during exercise, so horses with adequate resting abduction may still develop dynamic collapse during work
- •Approximately 1 in 5 laryngoplasty cases will show cartilage instability during exercise despite adequate resting abduction; consider this when setting post-operative expectations with owners
Key Findings
- •Median arytenoid cartilage abduction grade declined from grade 2 at 1 week to grade 3 by week 6 postoperatively, with grade 3 maintained long-term (mean 33 months follow-up)
- •Strong correlation (ρ = 0.89, P < 0.001) existed between week 6 and long-term abduction grade, but poor correlation between week 1 and long-term (ρ = 0.43, P = 0.1)
- •Arytenoid cartilage instability during exercise occurred in 7/33 horses (21%) and was not significantly associated with resting abduction grade (P = 0.50) or magnitude of postoperative abductory loss (P = 0.64)