The influence of positioning and torticollis on the development and treatment of abnormal infant head shapes
The purpose of this project was to investigate how positioning and torticollis influence the development and treatment of abnormal head shapes. Study one is a regression analysis to determine if time in inclined positioning equipment, birth (singleton or multiple), and sex are predictors of brachycephaly and/or severe plagiocephaly. Charts of 4-month-old infants were reviewed. Two binomial logistic regression analyses were done. The two dependent variables were presence of brachycephaly (cephalic index ≥ 92) or not, and presence of severe plagiocephaly (cranial vault asymmetry ≥ 12 mm) or not. The model for presence or absence of cephalic index ≥ 92 was significant. Only hours spent in incline was significant. The model for presence or absence of cranial vault asymmetry (CVA) was not significant. Study two determined reliability and validity of using Image J software to measure torticollis from digital images. Using Image J software, two physical therapy students measured the head tilt of 24 infants from digital images of the infants. The images were printed and manually measured by the principal investigator. All measurers were blinded to the measurements of each other and to previous measurements from an earlier session. ICC analyses were done to determine inter and intra rater reliability of the Image J software measurement method. A paired samples t-test was done comparing Image J measurements to the manual measurements to determine concurrent validity. All ICCs were above .75. Inter and intra-rater reliability was established. There was no significant difference comparing Image J measurements and manual measurements. Concurrent validity was established. Study three is a retrospective comparative analysis of the effect of age and head tilt on the amount of change in CVA in infants with plagiocephaly who receive dynamic orthotic cranioplasty (DOC) band treatment. Charts of infants with CVA ≥ 12mm who received DOC band treatment were reviewed. A two-way ANOVA was performed comparing age (< 5 months, ≥ 5 months) and head tilt (< 5 degrees ≥ 5 degrees) at the beginning of treatment. The dependent variable was change in CVA. The interaction effect between age and head tilt was not significant. Analysis of the main effect of age showed that infants < 5 months of age demonstrated significantly greater change in CVA than older infants. There was no significant difference in change in CVA measurements for infants with < 5 degrees of head tilt compared to ≥ 5 degrees. This project provides new information on how inclined equipment contributes to the development of brachycephaly. It introduces a new software method for measuring torticollis. It informs that infants with torticollis achieve similar change in CVA from DOC band treatment as infants without torticollis, while emphasizing the need for physical therapy during DOC band treatment.