Cadaver sample
An equine larynx/hyoid specimen from a harness racehorse was acquired to explain the cause of this unusual disorder (Figure 5). When manual pressure was applied on the thyrohyoid bone (only) approximately 1 cm distal to the articulation between the thyrohyoid bone and thyroid cartilage (thyrohyoid articulation) a similar compression of the base of the epiglottis (Figure 5 bottom right) as witnessed videoendoscopically was created. This compression visually obscures the vocal folds as the base of the epiglottis narrows and forms a U-shape.