Postoperative race performance is not correlated with degree of surgical abduction after laryngoplasty in National Hunt Thoroughbred racehorses.
OBJECTIVE
To (1) assess the degree of arytenoid cartilage abduction lost after laryngoplasty (LP) in Thoroughbred National Hunt racehorses and (2) to correlate postoperative racing performance with degree of arytenoid abduction after LP.


METHODS
Case series.


METHODS
National Hunt Thoroughbred racehorses (n=68).


METHODS
Grade of postoperative arytenoid abduction for National Hunt racehorses that had LP with ventriculocordectomy was assessed at 1 day, 6 days, and 6 weeks after LP. Race records were analyzed to ascertain if there was correlation between the degree of arytenoid cartilage abduction and various measures of race performance (return to racing postoperatively, total earnings in 5 races immediately postoperatively, and lifetime number of starts postoperatively).


RESULTS
Median postoperative arytenoid abduction was grade 2 on day 1 but had decreased to grade 3 by 6 weeks. Horses with grades 1, 2, and 3 abduction 1 day after surgery had median losses of 1, 1, and 0.5 abduction grades, respectively, at 6 weeks. Horses with grade 1 abduction on day 1 were significantly more likely to lose abduction by day 6 after surgery than horses with grade 3 abduction on day 1. There was no statistically significant correlation between the postoperative grade of arytenoid abduction at any time point and earnings in 5 races after surgery, likelihood of racing postoperatively, or total number of lifetime race starts postoperatively.


CONCLUSIONS
Horses with maximal (grade 1) surgical arytenoid abduction are significantly more likely to suffer postoperative loss of abduction than those with grade 3 abduction. Postoperative grade of abduction does not appear significantly correlated with markers of racing performance in National Hunt racehorses; however, very few horses with poor (grade 4 or 5) abduction were included and thus conclusions regarding racing performance in such horses cannot be drawn from this study.


CONCLUSIONS
Seemingly, most horses with grade 3 laryngeal abduction can race successfully and perhaps surgeons should not be disillusioned by the appearance of only moderate (grade 3) abduction in the long term after LP in racehorses.
Barakzai
Safia Z
SZ
Division of Veterinary Clinical Science, Royal (Dick) School of Veterinary Studies, Easter Bush Veterinary Centre, University of Edinburgh, Easter Bush, Roslin, UK. safia.barakzai@ed.ac.uk
Boden
Lisa A
LA
Dixon
Padraic M
PM
D000818:Animals; D005260:Female; D006736:Horses / Q000502:physiology / Q000601:surgery*; D007817:Laryngeal Cartilages / Q000601:surgery; D007818:Laryngeal Diseases / Q000601:surgery / Q000662:veterinary*; D007825:Laryngectomy / Q000662:veterinary*; D007830:Larynx / Q000601:surgery; D008297:Male; D011183:Postoperative Complications / Q000662:veterinary; D012420:Running / Q000502:physiology