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Updated: Jul 29, 2026
Behavioral and Locomotor Measurements Using an Open Field Activity Monitoring System for Skeletal Muscle Diseases
Published on: September 29, 2014
Abdominal and lower extremity muscles activity and thickness in typically developing children and children with
Sun-Young Ha1, Yun-Hee Sung1,2
1Department of Physical Therapy, Graduate School, Kyungnam University, Changwon, Korea.
Insights
Children with developmental delays show different muscle activity and thickness in their abdomen and legs compared to typically developing peers. Muscle tone characteristics are crucial for effective interventions in pediatric developmental delay.
Area of Science:
- Pediatric Physical Therapy
- Developmental Pediatrics
- Biomechanics
Background:
- Children with developmental delays often exhibit altered motor control and muscle function.
- Understanding differences in muscle activity and thickness is key for targeted interventions.
Purpose of the Study:
- To compare abdominal and lower extremity muscle activity and thickness between typically developing children and those with hypotonia or spasticity.
- To identify specific muscle groups that differ in function and structure based on developmental status.
Main Methods:
- Electromyography (EMG) to assess muscle activity of the rectus abdominis and quadriceps.
- Ultrasonography to measure the thickness of the external oblique, internal oblique, and transversus abdominis muscles.
- Measurements were taken at rest and during activity in 35 children (13 typically developing, 10 with hypotonia, 12 with spasticity).
Main Results:
- Significant differences in rectus abdominis and quadriceps muscle activity were observed across groups at rest and during activity (P<0.05).
- Significant differences in external oblique and transversus abdominis muscle thickness were found during activity (P<0.05).
- Significant differences in external oblique and internal oblique muscle thickness were noted in the sitting position (P<0.05).
Conclusions:
- Children with developmental delays, specifically hypotonia and spasticity, exhibit distinct patterns of abdominal and lower extremity muscle activity and thickness.
- Muscle tone characteristics significantly influence muscle function and morphology in children with developmental delays.
- Intervention strategies for pediatric developmental delay should account for individual muscle tone profiles for optimal efficacy.
Abstract:
We investigated abdominal and lower extremity muscle activity and thickness in typically developing children and children with developmental delays. A total of 35 children participated: typically developing peers (n=13), children with hypotonia (n=10), and children with spasticity (n=12). Muscle activity and thickness were measured at rest and during activity. Electromyography was used to measure abdominal and lower extremity muscle activities, and abdominal muscle thickness was measured using ultrasonography. There was a significant difference between the groups in the activity of the rectus abdominis and quadriceps muscles at rest and during activity (P<0.05). There was a significant difference between the groups in the thickness of the external oblique and transversus abdominis muscles during activity (P<0.05). There was a significant difference between the groups in the thickness of the external oblique and internal oblique muscles in the sitting position (P<0.05). Therefore, the characteristics of muscle tone should be considered when applying interventions to children with developmental delay.
