Submandibular Push Exercise Using Visual Feedback from a Pressure Sensor in Patients with Swallowing Difficulties: A Pilot Study

Abstract

Objectives: We aimed to determine the usefulness and effectiveness of a submandibular push exercise with visual feedback from a pressure sensor in patients with dysphagia through continuous exercise sessions. Methods: Twelve patients with dysphagia of various etiologies were included. A total of five exercise sessions (every 3 or 4 days) over three weeks were conducted. During the submandibular push exercise, patients were instructed to maintain a maximum force for 3 s, repeated for 1 min to measure the number of exercises, the maximum pressure, and the area of the pressure-time graph. We statistically compared the values of each exercise trial. Results: Among the 12 patients, eight completed the exercise sessions. As the number of exercise trials increased, the maximum pressure and the area in the pressure-time graph showed a significant increase compared to the previous attempt (p < 0.05). The maximum pressure and the area of the pressure-time graph improved from the first to the fourth session (p < 0.05). The values were maintained after the fourth session, and there was no significant difference between the fourth and the fifth exercise (p > 0.05). There was no significant difference between successful and non-successful groups, except for the Modified Barthel Index (p < 0.05). Conclusion: Through repetitive exercise training, the submandibular push exercise using visual feedback from a pressure sensor can be applied as an exercise method to strengthen swallowing related muscles, such as the suprahyoid and infrahyoid muscles. However, additional studies including more patients and a long-term study period are warranted to evaluate the effects of the exercise for improvement of dysphagia.

Keywords: CTAR; Shaker exercise; infrahyoid; submandibular push exercise; suprahyoid.

Figure 1

Three tongue motions for submandibular push exercise. (a) With the tongue pulled back, the bottom of the tongue was strongly pressed against the bottom of the mouth. (b) Tongue was turned over and the roof of the mouth was pressed strongly against the underside of the tongue. (c) Tongue was turned over and the tip of the tongue was directed to the back of the neck as far as possible.

Figure 2

(A) A graph explaining the pressure force over time during submandibular push exercise. Redline, the force applied to the sensor over time; Blueline, the maximum force during the measurement time; Greenline, the integral value of force-time graph. (B) Load cell pressure sensor and monitoring of pressure sensor during the submandibular push exercise, which used visual feedback [14].

Figure 3

Comparison of the number of exercises for each trial. Count—the number of exercises; D1, 2, 3, 4, 5—dysphagia therapy (submandibular push exercise) trial times. The dots in the graph represent values(count) for each patient.

Figure 4

Comparison of the maximum pressure for each trial. Fmax—maximum pressure; D1, 2, 3, 4, 5—dysphagia therapy (submandibular push exercise) trial times. The dots in the graph represent values(Fmax) for each patient.

Figure 5

Comparison of the area of pressure-time graph for each trial. Area—the area of pressure-time graph; D1, 2, 3, 4, 5—dysphagia therapy (submandibular push exercise) trial times. The dots in the graph represent values (area of pressure-time graph) for each patient.