Purpose: Trunk position may influence motor, cognitive, and social development during infancy and early childhood and has not been quantitatively assessed. The purpose of this study was to assess the trunk positions of infants born at term and preterm in supine using a computerized pressure mat.
Methods: Trunk position was represented as a ratio of head and pelvis to trunk pressure. Eighteen healthy infants born preterm with a mean gestational age of 31.9 weeks (25.0–34.6) and fifteen healthy infants born at term with a mean gestational age of 38.9 weeks (37.3–40.6) were assessed at 38 to 43 weeks gestational age.
Results: Infants born at term spent more than two-thirds of the time in either flexed or neutral trunk positions. No significant differences were found between infants born preterm and those born at term in total duration of flexion or extension or in flexion event duration.
Conclusion: This study provides evidence that infants born preterm may not exhibit greater trunk extension tendencies in supine than infants born at term. Results should be interpreted with caution, however, because of the small sample size and large variability observed within the subject groups. Infants born at less than 30 weeks of gestation may demonstrate greater extension tendencies than those born at more than 30 weeks of gestation.