Hyoid movement and laryngeal penetration during sequential swallowing

Area of Science:

• Deglutition biomechanics
• Swallowing physiology
• Videofluoroscopy analysis

Background:

• Sequential swallowing involves complex hyoid bone and laryngeal movements.
• Understanding these movements is crucial for identifying dysphagia risk.
• Previous research has not fully elucidated the relationship between hyoid trajectory and laryngeal penetration during sequential swallowing.

Purpose of the Study:

• To examine hyoid bone movement during sequential swallowing.
• To evaluate the relationship between hyoid trajectory patterns and swallowing types.
• To assess the association between these patterns and laryngeal penetration.

Main Methods:

• Twelve healthy adults participated in videofluorography during sequential swallowing.
• Swallowing was classified into i-Segmental (opened vestibule) and i-Continuous (closed vestibule) types.
• Hyoid bone's 2D movement trajectories were analyzed and categorized into patterns L, X, and U.

Main Results:

• A significant interaction was found between swallowing type and hyoid trajectory pattern (Two-way ANOVA).
• The highest incidence of laryngeal penetration occurred with the i-Continuous swallowing type combined with Pattern L hyoid trajectory.
• Specific swallowing pattern combinations were identified as potentially prone to penetration.

Conclusions:

• Sequential swallowing involves distinct hyoid movement patterns and their interaction with swallowing type influences laryngeal penetration risk.
• The i-Continuous swallowing type coupled with a Pattern L hyoid trajectory represents a high-risk combination for laryngeal penetration.
• These findings are relevant for managing dysphagia, but further investigation in patient populations is warranted.