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Development of the lateral equilibrium reaction in stance
H Perham1, J E Smick, A Hallum
1Division of Physical Therapy, Stanford University School of Medicine, CA.
Developmental Medicine and Child Neurology
|December 1, 1987
Summary
This study shows that a functional lateral equilibrium reaction in children develops after two years of age, with lower extremity responses being most consistent. This finding is crucial for understanding typical motor development.
Area of Science:
- Pediatric physical therapy
- Developmental motor control
- Human movement science
Background:
- Assessing lateral equilibrium reactions is vital for understanding postural stability in children.
- The development of these reactions is a key indicator of normal motor development.
- Previous research has not fully detailed the progression of lateral equilibrium reactions in early childhood.
Purpose of the Study:
- To assess the development of lateral equilibrium reactions in normally developing children aged nine months to five years.
- To establish a scoring system and checklist for describing these reactions.
- To identify age-related patterns and variations in the development of lateral equilibrium reactions.
Main Methods:
- A cohort of 80 normally developing children aged 9 months to 5 years was studied.
- A novel scoring system and checklist were used to evaluate the presence and character of lateral equilibrium reactions.
- Children were assessed for responses to lateral tilts.
Main Results:
- The earliest non-functional response was observed at nine months.
- Functional responses to both sides of tilt were not consistently seen until after two years of age.
- A progressive increase in functional responses occurred between 12 and 18 months, with a notable decrease at 21-24 months, followed by full functional responses in 3 and 5-year-olds. Lower extremity patterns were the most consistent component of functional responses.
Conclusions:
- Functional lateral equilibrium reactions develop significantly after two years of age.
- Lower extremity responses are the most reliable indicator of a functional reaction.
- Variations in trunk, upper extremity, and head movements suggest individual developmental trajectories rather than strict patterns for these segments.
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