Dynamic laryngeal collapse associated with poll flexion as a complication of laryngeal tie-forward surgery in three harness racehorses.

Abstract

To report dynamic laryngeal collapse (DLC) associated with poll flexion as a potential complication of the laryngeal tie-forward procedure (LTFP) in harness racehorses. Short case series. Three harness racehorses. Preoperative and postoperative medical records of all harness racehorses that underwent the LTFP were reviewed, as were high-speed treadmill videoendoscopy recordings of 35 horses that returned for upper airway evaluation postoperatively. One standardbred and two Norwegian coldblooded trotters in which dorsal displacement of the soft palate had been initially diagnosed were found to have bilateral arytenoid cartilage and vocal fold collapse associated with poll flexion after the LTFP. These three horses were otherwise clinically normal when exercised in free head carriage. Dynamic laryngeal collapse associated with poll flexion can occur as a complication after the LTFP in harness racehorses and should be considered as a differential in horses with persistence of airway problems after surgery. Postoperative DLC may be underdiagnosed in harness racehorses because this complication is obvious only when horses are driven with bit and reins during high speed treadmill or overground videoendoscopy.