The Effects of Cranio-cervical Flexion on Activation of Swallowing-related Muscles

We tested the effects of cranio-cervical flexion (CCF) on activation of swallowing-related muscles while swallowing liquid in a sample of 45 healthy volunteers. Activation following CCF movement was examined across two positions (supine and sitting) and, three pressure levels and two different postures were examined in each condition, respectively. When CCF was applied, activation of swallowing-related muscles was significantly increased compared to the neutral neck position, and such findings were found across both the supine and sitting positions. Also in the supine position, when the pressure level of the stabilizer was escalated, there was a significant difference in the activity of the swallowing-related muscles compared to the baseline level. In conclusion, our results suggest that CCF may be a viable method to enhance the effectiveness of swallowing-related muscles by changing neck position. When CCF is applied, the stability of the deep flexor muscles must be secured first after which superficially located muscles may better assist swallowing with less effort.