Objectives To characterize early developmental trajectories of selective motor control (SMC) in very preterm infants and examine associations with later cerebral palsy (CP) diagnosis and gross motor function.

Methods Very preterm infants (<32 weeks’ gestation) were recorded every 2–4 weeks until 5 months post-term age (PTA). SMC was scored from 352 videos (n=47 infants; 12 with CP) using BabyOSCAR, a validated observational tool. Linear mixed models examined SMC trajectories by CP diagnosis and Gross Motor Function Classification System (GMFCS) level. ROC 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 41–63 weeks, group differences emerged and widened (p<0.001). Change in BabyOSCAR score from 40–45 weeks predicted CP with 92% sensitivity and 100% specificity (AUC=0.98). GMFCS groups showed distinct trajectories, with children classified as GMFCS III–V changing scores less. Infants with unilateral CP showed increasing asymmetry from 42 weeks PTA.

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.

CP is a member of the General Movements Trust speakers bureau

Research reported in this publication was supported, in part, by the National Institutes of Health's National Center for Advancing Translational Sciences, Grant Number KL2TR001424.

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Ethics committee/IRB of Lurie Children's Hospital gave ethical approval for this work

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