“Submental sEMG and Hyoid Movement During Mendelsohn Maneuver, Effortful Swallow, and Expiratory Muscle Strength Training”
Summary by Katherine Duncan
Introduction:
For patients with dysphagia characterized by impaired swallowing musculature or decreased range of motion of head or neck structures are commonly instructed to use swallow maneuvers as a form of therapy. The most common swallow maneuvers are the supraglottic swallow, the super-supraglottic swallow, the Masako technique, the effortful swallow, and the Mendelsohn maneuver. The effortful swallow and the Mendelsohn maneuver both focus on correcting hyoid movements during swallow. Effortful swallow increases hyoid vertical displacement, the duration of hyoid excursion, duration of UES opening, and the amplitude of submental muscle activation in healthy adults. Surface electromyography (sEMG) is the best tool for assessing the submental muscle group that causes hyoid bone movement during the pharyngeal stage of swallowing.
Purpose:
To examine the effects that effortful swallow, Mendelsohn maneuver, and expiratory muscle strength training (EMST) had on hyoid motion and submental activation in healthy adults in order to characterize task-specific and overload properties of each task. The purpose was to prove whether or not the trajectory of hyoid motion and the elevation angles and displacements of hyoid movements would be different between tasks.
Method:
Twenty-five healthy adults were chosen to participate in the experimental study by completing normal swallow, Mendelsohn maneuver, effortful swallow, and EMST tasks. A videofluoroscopy and surface electromyography recording were used to record data. The sEMG signals were displayed on computer screens and provided feedback for participants. Scripted directions for the effortful swallow were as follows: “As you swallow, squeeze hard with all of your throat muscles” (Logemann, 1999). This task was practiced until five out of five were completely successfully by doubling the normal sEMG amplitude. See figure below.
Results:
The study supported the hypotheses concerning trajectory of hyoid motion and the elevation angles and displacements of hyoid movements. The three tasks that included the actual swallows had greater hyoid displacement values than that of the EMST task. The sEMG measures were highest for the Mendelsohn maneuver and effortful swallow, especially concerning hyoid displacement. The change in the angle of the hyoid displacement was significantly higher for the Mendelsohn maneuver with effortful swallow and the EMST task close behind.
The study also showed that the normal swallow exhibited significantly smaller sEMG measures versus the Mendelsohn maneuver, effortful swallow, or EMST task. With Mendelsohn maneuver and effortful swallow, the submental muscle activity increased resulting from the intentional “squeezing” during the hard swallow.
Important for the SLP:
Rehabilitation techniques, such as the Mendelsohn maneuvers and effortful swallow that are designed to improve swallow safety and challenge the physiology of the swallow, are commonly used to treat dysphagia. The effortful swallow specifically modifies the hyoid bone movement and increases the activation of the submental muscle group when compared with normal swallow tasks.
Wheeler-Hegland, Karen M., John Rosenbek, Christine M. Sapienza. (2008, October). Submental sEMG and Hyoid Movements During Mendelsohn Maneuver, Effortful Swallow, and Expiratory Muscle Strength Training. Journal of Speech, Language, and Hearing Research, 51, 1072-1087.