Emergence of Selective Motor Control in Early Infancy: A Longitudinal Study of Infants Born Preterm with and without
Colleen Peyton1, Theresa Sukal Moulton1, David Aaby2
1Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL; Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, IL.
Insights
Selective motor control (SMC) develops rapidly in infants but is altered in those born very preterm who later develop cerebral palsy (CP). Early SMC trajectories can predict CP diagnosis and functional motor outcomes.
Area of Science:
- Developmental neuroscience
- Pediatric neurology
- Motor control research
Background:
- Infants born very preterm (<32 weeks' gestation) face risks for neurodevelopmental disorders.
- Cerebral palsy (CP) is a common motor disability in preterm infants.
- Early identification of CP risk is crucial for timely intervention.
Purpose of the Study:
- To characterize early selective motor control (SMC) development in very preterm infants.
- To investigate the association between early SMC trajectories and later CP diagnosis.
- To examine the relationship between SMC and gross motor function (GMFCS levels).
Main Methods:
- Longitudinal video analysis of SMC using the BabyOSCAR tool in 47 very preterm infants.
- SMC scoring occurred every 2-4 weeks until 5 months post-term.
- CP diagnosis confirmed at 2 years; linear mixed models and ROC curves analyzed data.
Main Results:
- SMC scores increased over time, with significantly slower gains in infants who developed CP.
- Early SMC changes (40-45 weeks) predicted CP with 92% sensitivity and 100% specificity.
- Distinct SMC trajectories were observed across GMFCS levels, with less change in GMFCS III-V.
Conclusions:
- SMC development is altered in very preterm infants with CP, especially those with severe motor impairment (GMFCS III-V).
- Early SMC trajectories may indicate developing corticospinal tract connectivity.
- SMC offers a potential early clinical marker for predicting functional motor outcomes in high-risk infants.
Objectives:
To characterize early developmental trajectories of selective motor control (SMC) in infants born very preterm and examine associations with later cerebral palsy (CP) diagnosis and gross motor function.
Study Design:
Infants born very preterm (<32 weeks' gestation) were recorded every 2-4 weeks until 5 months post-term age. SMC was scored from 352 videos (n = 47 infants; 12 with CP) using BabyOSCAR, a validated observational tool. CP diagnosis was then confirmed at 2 years of age. Linear mixed models examined SMC trajectories by CP diagnosis and Gross Motor Function Classification System (GMFCS) level. Receiver operating characteristic curves tested the ability of early SMC change (40-45 weeks) to predict CP.
Results:
SMC scores increased over time, but infants with CP showed slower gains. Between 41 and 63 weeks, group differences emerged and widened (P < .001). A change in BabyOSCAR score from 40-45 weeks predicted CP with 92% sensitivity and 100% specificity (area under the curve = 0.98). GMFCS groups showed distinct trajectories, with children classified as GMFCS III-V exhibiting less change in scores. Infants with unilateral CP showed increasing asymmetry from 42 weeks post-term age.
Conclusions:
SMC develops rapidly after term age but is altered in infants with CP, particularly among those later classified as GMFCS III-V. Early trajectories may reflect emerging corticospinal connectivity and offer a clinically useful marker of functional motor outcomes.
