Sonographically measured hyoid bone displacement during swallow in preschool children: a preliminary study

This study explored normative parameters regarding maximum displacement of hyoid bone movement during spontaneous swallows using ultrasound (US) in a sample of healthy preschool children. We hypothesized that consistency and bolus size would influence hyoid movement, but gender would not be a factor.

Parental questionnaire responses and sensorimotor examinations were utilized to determine subject eligibility. Subjects were presented randomized bolus volumes of thin liquids/puree via a spoon while the US probe was placed submentally in the midsagittal plane. Maximum hyoid bone displacement was determined following a frame-by-frame analysis of the US recording during spontaneous swallowing of discrete bolus sizes.

Twenty-nine subjects produced 346 swallows that were subsequently analyzed. Significant findings (p < 0.05) included a gender effect with the smallest bolus of liquids presented. Bootstrap estimates based on our sample revealed that 99% of preschool children would present with hyoid bone displacement within 0.3 cm of our sample.

Based on our early experience, we were able to observe and measure changes in hyoid bone position during swallowing in preschoolers, which may be gender related. More studies are needed to corroborate our findings. In addition, comparisons of maximum hyoid displacement are warranted in subjects that present with feeding delays.