Wednesday, September 26, 2018 7:35 AM–9:00 AM ePosters: P10. Infant positioning impacts neck and back muscle activity: a pilot study exploring implications for spinal development

Abstract

BACKGROUND CONTEXT Since 1992, pediatricians have recommended that all infants be placed to sleep in the supine or side-lying position to reduce the risk of Sudden Infant Death Syndrome (SIDS). Although this policy successfully reduced the incidence of SIDS by nearly 50%, questions regarding the positional impact on musculoskeletal and motor development have since surfaced. Studies have linked prone positioning to extensor muscle development and motor milestone achievements, and some believe a link can be made between infant positioning and idiopathic infantile scoliosis. Recently, a relationship between muscle forces and spinal curvatures, particularly hyperkyphosis, was found in fetal chicks, leading to more questions regarding the role of the paraspinal muscles in early spinal development/deformity. PURPOSE The purpose of this pilot study is to examine relationships between infant positions and neck or back muscle activity using electromyography (EMG). STUDY DESIGN/SETTING Electromyographic research study. PATIENT SAMPLE Healthy infants aged 2-7 months. OUTCOME MEASURES Normalized mean EMG data. METHODS Seven healthy infants (mean 5.2 months, 5 male) were enrolled in the study. Surface EMG recorded muscle activity of bilateral cervical paraspinal and erector spinae muscles during five 30-second tasks: laying prone, laying supine, held in arms, held in a baby carrier, and in a car seat. EMG data was normalized to the prone task, and paired t-tests were used to compare to the prone position (p RESULTS Infants exhibited significantly more erector spinae activity during prone positioning compared to all other tasks, and twice as much compared to the supine position (p CONCLUSIONS This first look at the muscle activity of healthy infants in common positions supports the importance of prone time in neck and back development. Prone time significantly increases erector spinae activity. As subject enrollment continues, the in-carrier position may show comparable neck muscle activity to the prone position, as the baby must support the weight of the head while upright.