Physiological movement disorder-like features during typical motor development | JoVE Visualize

Area of Science:

Neuroscience
Developmental Pediatrics
Movement Disorders

Background:

Understanding physiological age-relatedness of movement disorder symptoms in healthy children is crucial for distinguishing normal development from pathology.
Previous research has focused on specific disorders, but a comparative analysis of age-relatedness across dyskinesia, dystonia, and ataxia in a healthy pediatric cohort is lacking.

Purpose of the Study:

To compare the physiological age-relatedness of dyskinesia (dystonia/choreoathetosis), dystonia, and ataxia rating scale scores in healthy children.
To investigate the relationship between different types of movement disorder-like features and age in a pediatric population.

Main Methods:

Three movement disorder specialists assessed dyskinetic features in 52 healthy children (ages 4-16) using the Dyskinesia Impairment Scale (DIS), which includes DIS-dystonia (DIS-D) and DIS-choreoathetosis (DIS-C).
Compared age-related regression coefficients of the DIS with data from previous studies on dystonia (Burke-Fahn-Marsden Movement and Disability Scales - BFMMS) and ataxia rating scales (SARA, ICARS, BARS).

Main Results:

Dyskinetic scores were obtained in 79% of children (DIS), 65% (DIS-D), and 17% (DIS-C). Dystonic and ataxic scores were more frequently captured (BFMMS: 98%, SARA/ICARS/BARS: 89%).
Age-related DIS and DIS-D scores showed significant correlations with age-related BFMMS scores (r=0.87, p<0.001), indicating an inverse age-relatedness for dystonic features.
Choreoathetotic (DIS-C) scores were age-independent, while ataxic scores demonstrated stronger age-related regression coefficients than dyskinetic and dystonic scores in younger children (4-8 years).

Conclusions:

Healthy children exhibit inverse age-relatedness for dystonic and ataxic scores, but not for choreoathetotic scores.
Dystonic features measured by DIS-D and BFMMS are interrelated and age-dependent.
Ataxic features show the most pronounced age-related expression, suggesting these physiological movement disorder-like features reflect the development of underlying motor centers.