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Updated: Aug 6, 2026

Quantified Assessment of Infant's Gross Motor Abilities Using a Multisensor Wearable
Published on: May 17, 2024
General movement assessment in infants with inherited metabolic disorders
Arend F Bos1, Sahar Salavati1, Francjan J van Spronsen2
1Division of Neonatology, Department of Pediatrics, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
Insights
Infants with inherited metabolic disorders often show atypical early movements. A low motor optimality score (MOS-R) and abnormal fidgety movements can indicate neurodevelopmental risks.
Area of Science:
- Neurology
- Metabolic Disorders
- Developmental Pediatrics
Background:
- Inherited metabolic disorders (IMD) are linked to neurodevelopmental issues.
- Early infant neurological assessment in IMD is not well-characterized.
- Understanding early motor repertoire is crucial for timely intervention.
Purpose of the Study:
- To describe the early motor repertoire in infants with IMD.
- To identify specific atypical movements in these infants.
- To correlate early motor patterns with neurodevelopmental outcomes.
Main Methods:
- Multi-center, retrospective study using prospectively collected videos.
- Included 25 infants with IMD at risk for CNS dysfunction.
- Utilized Prechtl General Movements Assessment (GMA) and MOS-R up to 20 weeks post-term.
Main Results:
- Poor repertoire general movements were observed in 9/25 infants.
- Abnormal or absent fidgety movements (FMs) were noted in 52% of infants.
- A MOS-R below 23, associated with adverse outcomes, was found in 64% of infants.
Conclusions:
- Atypical early motor repertoire is common in infants with IMD.
- Abnormal FMs and low MOS-R scores are indicators of neurodevelopmental risk.
- GMA and MOS-R show moderate associations with development, with potential for later deterioration.
Background:
Several inherited metabolic disorders (IMD) are associated with neurodevelopmental problems, but clinically, the infants' neurological condition during their first months has not been well described. We aimed to describe infants' early motor repertoire, to identify specific atypical movements, and to determine its relation to outcome.
Study Design:
Multi-centre cross-sectional retrospective study with prospectively collected videos.
Subjects:
Twenty-five children with IMD at risk of central nervous system dysfunction.
Measures:
From videos taken until 20 weeks' post-term age, we performed Prechtl General Movements Assessment (GMA) and the revised motor optimality score (MOS-R). Descriptive data on neurodevelopmental outcome were retrospectively collected, and classified as normal or abnormal.
Results:
Videos of writhing general movements were available in 13 of 25 infants. Four infants had normal, nine had poor repertoire general movements. At 9-20 weeks' post-term, 17 of 25 infants had normal and three had abnormal fidgety movements (FMs), and they were absent in three. In another two infants we observed a variant of FMs with high speed, small amplitude: so-called fidgety-like movements. Sixteen infants obtained a MOS-R below 23, without specific atypical movements or postures. A MOS-R below 23 was related to neurodevelopmental outcome, sensitivity 71% (95%-confidence-interval 44-90%) and specificity 80% (28-99.5%).
Conclusion:
The early motor repertoire in infants with IMD at high risk for adverse neurodevelopment is often atypical. Aberrant fidgety movements occurred in 24%, and a MOS-R below 23 in 64% of infants. Associations of GMA and MOS-R with development were moderate, because in this population outcomes may deteriorate over time.

