Purpose: (1) To compare the kinematic motion of the hyoid bone and the epiglottis in healthy controls and a sample of patients with dysphagia of different etiologies, and (2) to evaluate the potential value of kinematic swallowing analysis to differentiate the mechanism of dysphagia.
Methods: We performed two-dimensional video motion analysis of the hyoid bone using videofluoroscopic images in nine controls without any swallowing difficulty, and seven patients with supratentorial stroke, three patients with inflammatory myopathy who showed dysphagia. Main outcome measures were: (1) horizontal and vertical excursion of the hyoid bone, and rotation of the epiglottis, and (2) trajectory of the hyoid bone and epiglottis during swallowing.
Results: Horizontal excursion of the hyoid bone and rotation of the epiglottis were reduced in patients with myopathy as compared to control and patients with stroke (P<0.05). Patients with dysphagia showed different patterns as compared to control in trajectory analysis according to their etiology.
Conclusion: We conclude that extent and pattern of movement of the hyoid bone and the epiglottis during swallowing were different according to etiology of dysphagia, and swallowing motion analysis could be applied to differentiate the mechanism of dysphagia.