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Published on: March 12, 2021
[Developmental changes in the Collis horizontal reaction analyzed using a three-dimensional video motion analysis
Mitsuhiro Nakajima1, Tasuku Miyajima, Michiro Iiyama
1Department of Pediatrics, Tokyo Medical University, Tokyo. n-32hiro@tokyo-med.ac.jp
Insights
The Collis horizontal reaction effectively tracks infant development. Analyzing upper limb movements provides an objective measure of physical development from 4-9 months old.
Area of Science:
- Pediatric development
- Biomechanics
- Motor control
Context:
- Infant motor skills evolve significantly between 4 and 9 months.
- The Collis horizontal reaction is a standard test for assessing infant reflexes.
- Assessing developmental milestones requires objective and reliable measurement tools.
Purpose:
- To evaluate the Collis horizontal reaction's utility in objectively measuring infant physical development.
- To analyze upper limb kinematic changes during the Collis horizontal reaction in infants aged 4-9 months.
- To correlate upper limb movement patterns with developmental progression.
Summary:
- A 3D motion analysis system tracked 38 infants (151 observations) from 4-9 months during the Collis horizontal reaction.
- Key metrics included forearm pronation speed, palm-down hand placement, and hand location relative to the body.
- Normal development correlates with the free hand moving under the shoulder as infants pronate and support with their palms.
Impact:
- The Collis horizontal reaction serves as a valuable, objective tool for assessing current and predicting future physical development in infants.
- This method allows for early identification of developmental trajectories through simple upper limb movement analysis.
- Provides insights into the biomechanics of infant postural control and motor learning.
Abstract:
At four months old, infants of 72% challenged with the Collis horizontal reaction touch the floor with the back of their free hand. As the infants grow older, the ratio of infants that open their free hand and perform a support reaction increases from 0% to 100%. At nine months old, all infants perform this support reaction with their free hand palm-side down. To assess infant development more accurately, we used a three-dimensional video motion analysis system to evaluate upper limb movement in 38 infants (total 151 times) from 4-9 months old during the second and third phases determined by the Collis horizontal reaction. By analyzing the constituent components of upper limb movement during the Collis horizontal reaction, we assessed the usefulness of the reactions as an objective tool to measure developmental changes in infants. During the analysis, we thought to assess the speed of the upper limb reaction was respect to pronating the forearm, supporting the body with the palm down, and location of their free hand. The analysis shows that if development progresses normally and infants pronate the forearm to support the body with the palm down, the central value at which their free hand is located moves to a point under the shoulder. The results suggest that in infants four to nine months old, the Collis horizontal reaction is an excellent method to assess not only the present physical development level, but also future physical development attainment by only evaluating developmental changes of upper limb movement only.
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