Pediatrics: Neuromuscular (part 1)

What does the CNS contain?

upper motor neurons

What neurons does the PNS have?

LMN

maintaining a stable position (sitting, standing)

static postural control

adjusting posture during movement, such as reaching or walking

dynamic postural control

responds to unexpected disturbances

reactive

adjustments maid in preparation for movement

anticipatory

How does postural control typically develop?

cephalocaudal (head to toe) and proximodistal

True or false: <1 years old have low force production

true

why/how can a child having low force production impact their movements?

constraint for sitting / standing

True or false: ROM is a typical limiting factor for posture in children

false

Explain the body geometry of children and how it develops

infants/children have larger heads compared to body size; changes during growth spurts (puberty )

True or false: sensory receptors are mature at birth

true

What is used as the primary information when first learning a task or in a novel environment across the lifespan ?

vision

true or false: children have a preference for reliance on motor input for postural orientation corrections

false - preference for visual reliance

describe the maturity of somatosensory receptors at birth

somatosensory receptors are mature at birth

How do children 6+ months use somatosensory inputs?

used to maintain sitting balance

how do children 4-6 years old use somatosensory information?

use somatosensory input for sensory conflict resolution

at what age is somatosensory input adult like?

7-10 years old

True or false: vestibular receptors are mature at birth

true

How do 7-10 year olds use vestibular input?

resolution of sensory conflict (adult-like manner)

what are neuromuscular contributions to postural control?

static, active, reactive, anticipatory

ability to maintain a stable position without significant movement; reflects ability to resist external forces

static postural control

how does muscle tone contribute to static postural control

maintains a baseline level of tension for stability

how does proximal stability contribute to static postural control?

strength and control in core & proximal joints allow for sustained postures

How do postural reflexes contribute to static postural control?

righting and equilibrium reactions provide automatic adjustments to maintain static positions

automatic responses that restore proper alignment of head and body

righting reflexes

automatic responses to maintain balance and stability during changes in the center of gravity or external perturbations

equilibrium reflexes

maintains or restores alignment of head and body with gravity or environment

righting reflexes

helps maintain balance & prevents falls when the body's postion or center of gravity shifts

equilibrium reflexes

true or false: righting reflexes move the body

false - righting reflexes move the head, equilibrium reflexes move the body

Describe static postural control of a newborn

limited; primarily rely on primitive reflexes

describe static control of a 3-4 month old

can hold head up briefly in prone; begin to activate trunk muscles

Describe static postural control of a 6-7 month old ?

independent sitting emerges; trunk & hip stability improve

describe static postural control of a 10-12 month old

pull to stand; maintains standing with support

describe static postural control of a child 12+ months old

gains static balance for standing independently & walking

maintaining or adjusting posture during voluntary movements or dynamic activities

active postural control

How does the coordination of agonist and antagonist muscles contribute to active postural control?

smooth transitions between movement and postural stability

What is critical for adjusting posture in real-time during active tasks ?

proprioceptive feedback

Describe active postural control of a 5-6 month old

begins reaching for objects in supported sitting; active trunk adjustments

Describe active postural control of a 7-9 month old

crawling & transiting between sitting and prone; dynamic trunk and limb control

Describe active postural control of a 10-12 month old

cruising along furniture; active balance control improves during weight shifts

Describe active postural control of a 2-3 year old

running/jumping/climbing require more advanced active control

ability to respond to unexpected external disturbances or perturbations

reactive postural control

How do automatic postural responses contribute to reactive postural control?

coordinated muscle response to maintain or restore balance

how do stretch reflexes contribute to reactive postural control ?

quick muscle activation in response to sudden changes in position or balance

Reactive postural control in infants (0-6 months)

relies on basic reflexes, limited reactive control

Reactive postural control in 6-9 month old:

emergence of protective extension

Reactive postural control in infants 12-18 month old:

begins to use stepping strategies to recover balance

Reactive postural control in 3+ year olds

faster, more efficient responses to perturbations

preparing the body for voluntary movements or potential disturbances prior to their occurrence

anticipatory postural control

how do feedforward mechanisms contribute to anticipatory postural control?

use prior experience and sensory info to prepare for expected movements

How does cerebellar control contribute to anticipatory postal control

coordinates timing and sequencing of anticipatory adjustments

Anticipatory control of infants (3-6 months)

limited; beginning to stabilize head and trunk during reaching

anticipatory control of 7-9 month old

prepares trunk and arms for reaching in sitting or prone

anticipatory control of 10-12 month old

anticipates the need to adjust posture for walking or transitions

anticipatory control of 2-4 year old

refinement, seen in tasks like jumping or throwing

anticipatory control of 5+ year old

adult-like; refined through practice and experience

Describe tone of an UMN

increased (spasticity)

describe reflexes in an UMN lesion

hyperreflexia

describe muscle bulk if a child has an UMN lesion (brain/spinal cord)

minimal atrophy (disuse)

True or false: with UMN lesions fasciculation are present

false - absent

Muscle tone with a LMN Lesion (peripheral nerves)

decreased tone (flaccidity)

Describe reflexes with a LMN lesion

hyporeflexia or absent

describe muscle bulk in a person with a LMN lesion

significant atrophy

Are fasciculations present in LMN lesions.

yes

What condition has a mixed/both motor neuron presentation?

neural tube defects

where is encephalocele usually found?

occipital region

absence of most of the brain

anencephaly

absence of the cerebral cortex; intact meninges & skull

hydranencephaly

formation of a rudimentary brainstem without cerebral or cerebellar hemispheres; skull does not form over the incomplete brain

anencephaly

When does anencephaly occur?

neural tube remains open; forebrain does not develop

What could cause anencephaly?

chromosomal abnormalities, maternal nutritional deficiencies

mildest form of spina bifida; missing laminate and spinous process

occulta

What could cause Spina Bifida ?

nutrition (folic acid deficiency), genetics, unknown

What is the 2nd most common congenital birth defect ?

myelomeningocele (MMC)

Prognosis for Spina Bifida at L1 & Above

household or non walker

prognosis for spina bifida at L2-3

household ambulation

prognosis for spina bifida at L3-4

household or community ambulation

Prognosis for spina bifida L5 and below

community ambulation

brainstem is displaced inferiorly beyond the foramen magnum, blocks CSF causing hydrocelphus

arnold Chiari malformations

What are signs and symptoms of Arnold Chiari Malformation?

bulging fontanelle, sun setting eyes, high pitched cry, behavioral changes, vomitting

what congenital conditions could hydrocephalus accompany?

Chiari malformation or spina bifida

How can a baby aware hydrocephalus ?

hemorrhage, infection, TBI, tumor