Effect of posture on swallowing.

Background: Swallowing is a systematic process. Any structural, physiological or neurological disturbance in this process may cause dysphagia. Although there are studies that report head/neck movements during mastication, there are fewer studies that show the effect of different head/neck postures on difficulty while swallowing.
Objectives: To observe the effect of different body postures on the self-perceived difficulty while swallowing in normal healthy subjects.
Methods: Participants were asked to swallow 25 ml of water in one go while sitting upright, sitting with head/neck flexed, head/ neck extended and lying supine. Following this, they had to rate their self-perceived difficulty while swallowing on a scale of 0-10, 0 being most easy and 10 being most difficult.
Results: 186 subjects with mean age 32.7 SD 9.04 participated in this study. It was found to be least difficult to swallow when subjects were asked to swallow in upright sitting position. Statistically significant differences were found between sitting upright, sitting with head/neck flexed, head/neck extended and lying supine.
Conclusion: Postural modification may help in rehabilitation of patients with dysphagia by affecting bolus flow to improve speed and safety of swallowing by closure of airways to prevent aspiration.