The effect of lateral shift of cricoid cartilage on pharyngeal swallowing.

Head rotation is widely used as one of the postural techniques for dysphagic patients. However, it cannot be used for patients with severe limitations to the range of motion of the neck. The purpose of this study was to determine the effect of applying pressure to the cricoid while swallowing and to explore the possibility of this maneuver as an alternative to head rotation. The swallowing function of 12 volunteers was examined with videofluorography under nine conditions: neutral, head rotated to the right, head rotated to the left, applying pressure to the cricoid on the right side at 5, 10, and 15 N, and applying pressure to the cricoid on the left side at 5, 10, and 15 N. To examine the effect of this maneuver on pharyngeal swallowing, the laterality of bolus flow was evaluated using 3 ml barium thin liquid from the posterior-anterior (P-A) view. The "pressing-cricoid" maneuver significantly altered the laterality of the bolus flow; the bolus flow was shifted to the side opposite to which the pressure was applied. The results of these changes were similar to those achieved with head rotation. These results demonstrated that the "pressing-cricoid" maneuver changes the bolus flow. This maneuver may have therapeutic value for the treatment of dysphagic patients as an alternative to head rotation.