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Isometric and Eccentric Force Generation Assessment of Skeletal Muscles Isolated from Murine Models of Muscular Dystrophies
Published on: January 31, 2013
Ability of very young children to produce reliable isometric force measurements
1School of Physical Therapy and Rehabilitation Science, University of Montana, Missoula, MT 59812, USA. carrie.gajdosik@umontana.edu
Insights
Measuring isometric muscle force in young children using a hand-held dynamometer (HHD) is reliable. This study found fair to excellent reliability for children as young as two years old.
Area of Science:
- Pediatric physical therapy
- Pediatric biomechanics
- Child development research
Background:
- Accurate measurement of pediatric muscle strength is crucial for assessing development and guiding interventions.
- Hand-held dynamometers (HHDs) offer a portable and accessible method for assessing muscle force.
- Establishing the reliability of HHD measurements in very young children is essential for clinical and research applications.
Purpose of the Study:
- To evaluate the reliability of measuring isometric muscle force in typically developing children aged two, three, and four years.
- To determine if age influences the reliability of hand-held dynamometer measurements in young children.
- To assess the impact of challenging behaviors on measurement reliability.
Main Methods:
- Forty-five typically developing children (aged 2-4 years) were divided into three age groups.
- Isometric muscle force (shoulder/elbow flexion/extension, knee flexion/extension) was measured twice using a hand-held dynamometer (HHD) within 5-9 days.
- Challenging behaviors and extra test trials were recorded to assess their influence on reliability.
Main Results:
- Intraclass correlation coefficients (ICCs) for the combined group ranged from 0.90 to 0.95, indicating excellent reliability.
- Reliability varied by age group, with ICCs ranging from 0.76-0.91 (2-year-olds), 0.85-0.92 (3-year-olds), and 0.54-0.94 (4-year-olds).
- The frequency of challenging behaviors did not correlate with measurement reliability.
Conclusions:
- Hand-held dynamometry (HHD) provides a reliable method for assessing isometric muscle force in typically developing children aged two years and older.
- Standardized procedures ensure fair to excellent reliability, supporting the use of HHD in pediatric populations.
- This methodology is valuable for tracking muscle development and informing therapeutic strategies in young children.
Purpose:
This study was designed to examine the reliability of measuring isometric muscle force in very young children with a hand-held dynamometer (HHD).
Methods:
Forty-five children aged two, three, or four years old and with typical development, were divided into three groups of 15 subjects each. Group 1 included two-year-old children (X age = 32 +/- 2.4 months), group 2 contained three-year-old children (X age = 43 +/- 3.8 months), and group 3 included four-year-old children (X age = 54 +/- 3.7 months). Isometric force for shoulder flexion, elbow flexion, elbow extension, knee flexion, and knee extension were measured with a HHD on two occasions separated by five to nine days. The frequency of challenging child behaviors and extra test trails also were recorded.
Results:
Intraclass correlation coefficients (ICCs) (2, 1) for the combined group (n = 45) ranged from 0.90 to 0.95. The ICCs (2, 1) for the two-year-old children ranged from 0.76 to 0.91, for the three-year-old group from 0.85 to 0.92, and for the four-year-old children from 0.54 to 0.94. The frequency of challenging behaviors did not appear to be related to the level of reliability.
Conclusion:
Using a HHD and standardized procedures, isometric force of children who are typically developing and as young as two years of age can be measured with fair to excellent reliability.
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