Development of low postural tone compensatory patterns in children - theoretical basis

Area of Science:

• Neurology
• Developmental Pediatrics
• Biomechanics

Background:

• Children with low postural tone, not linked to central nervous system damage, present a challenge in understanding upright posture maintenance.
• Existing literature suggests compensatory mechanisms enable these children to achieve verticalization, potentially at the cost of posture quality.

Purpose of the Study:

• To investigate the mechanisms enabling upright posture in children with low postural tone without central nervous system (CNS) damage.
• To differentiate types of low postural tone based on observed developmental stages and postural muscle engagement.
• To analyze the neurodevelopmental implications of compensatory strategies on body posture quality.

Main Methods:

• Observational study of children's developmental stages.
• Classification of postural tone into normotonia and low postural tone (without CNS damage).
• Identification and characterization of two distinct types of low postural tone: spastoidal and atetoidal.

Main Results:

• Two types of low postural tone were identified: spastoidal (local deep muscle hypotonia compensated by global superficial muscle hypertonia) and atetoidal (hypotonia in both deep and superficial muscles).
• Children with inefficient active subsystems rely heavily on passive subsystem qualities (e.g., ligaments, bone structure, passive muscle features) for verticalization.
• Compensatory mechanisms, while facilitating upright posture, negatively impact overall body posture quality.

Conclusions:

• Low postural tone in children without CNS damage involves specific compensatory mechanisms for achieving upright posture.
• The spastoidal and atetoidal classifications provide a framework for understanding variations in low postural tone.
• Compensatory strategies for verticalization in children with low postural tone lead to a diminished quality of body posture from a neurodevelopmental perspective.