Dynamic bilateral arytenoid and vocal fold collapse associated with head flexion in 5 Norwegian Coldblooded Trotter racehorses

Bilateraler dynamischer Kehlkopfkollaps in Zusammenhang mit der Kopf-Halshaltung im Tölt bei einem Islandpferd

“…Bilateral dynamic laryngeal collapse has previously only been reported in harness racehorses, and Norwegian Coldblooded Trotters seem predisposed to this disorder relative to Standardbreds (Strand et al 2004, Fjordbakk et al 2008. The diagnosis can only be established while the affected individual is driven into the bit during high-speed treadmill videoendoscopy wearing a bridle and head check rein.…”

“…If exercised with only a halter and free head carriage, no abnormalities are noted. This disorder appears to be a separate entity from recurrent laryngeal neuropathy (Strand et al 2004, Fjordbakk et al 2008). Resting videoendoscopy revealed no upper respiratory tract abnormalities in this case, as is typical for this syndrome.…”

“…Schlüsselwörter: Islandspferd, dynamisch, Kehlkopfkollaps, Versammlung, Kopfhaltung, Tölt, Laufband, Videoendoskopie examination is necessary to induce the upper respiratory tract obstruction (Strand et al 2004. Left sided arytenoid cartilage collapse, vocal fold collapse and axial deviation of the aryepiglottic folds are the most common disorders affecting the larynx (Tan et al 2005.These disorders are most often present regardless of head and neck position.…”

“…Left sided arytenoid cartilage collapse, vocal fold collapse and axial deviation of the aryepiglottic folds are the most common disorders affecting the larynx (Tan et al 2005.These disorders are most often present regardless of head and neck position. Bilateral vocal fold and arytenoid cartilage collapse associated with poll flexion is a newly described disorder most frequently diagnosed in Norwegian Coldblooded Trotters (Strand et al 2004, Fjordbakk et al 2008). This disorder is often associated with other abnormalities of the upper respiratory tract, such as axial deviation of the aryepiglottic folds and dorsomedial deviation of the epiglottic margins, and has therefore recently been denoted bilateral dynamic laryngeal collapse (Fjordbakk et al 2008).…”

“…Although they race with different types of head-checks enforcing "high" head and neck position, poll flexion occurs when they are restrained onto the bit. Correct diagnosis is only made videoendoscopically when the horse is driven into the bit by using full racing gear and long reins on the high-speed treadmill (Strand et al 2004, Fjordbakk et al 2008). This report describes the first case of bilateral dynamic laryngeal collapse diagnosed in an Icelandic Horse evident only during the töl-ting gait.…”