Postural Control and Gait Development Flashcards
what are the 3 components of balance? what are the 3 subcategories of each component?
- individual
- motor
- sensory
- cognitive - environment
- support surfaces
- cognitive load
- sensory context - postural tasks
- steady state
- proactive
- reactive
what are the three components contributing to posture
task
individual
environment
what are 6 components of an individual that will contribute to their postural systems
MSK
cognitive resources
cognitive strategies
sensory organization
sensory systems
ms synergies
what is balance
interplay b/w postural control/tasks and individual and environment
development of postural control reflects changes in… (2)
strength
mass of body segments
- body proportions
development of postural control reflects development of what postural control components (5)
- NM responses
- sensory systems
- sensory strategies for organization of balance
- internal representation (perception to action)
- adaptive and anticipatory mechanisms
1mo milestone
lifting head
4-7mo milestones
sitting w support
–> sitting independently
8-10mo milestone
creeping
–> crawling
at what age is the milestone of pulling to stand achieved
9-10mo
12-13mo milestone
independent stance
14-18mo milestone
walking
what are 3 theoretical frameworks
dynamic systems & ecological
neuronal group selection
perception-action
what is dynamic systems and ecological theories
organization of elements w/i postural control system is shaped by task & environment
- development is non-linear bc of variations in postural control system and how individual is creating that
how does dynamic systems and ecological theories define motor behavior
self-organization of body systems to find best solution to task
neuronal group selection theory: variation vs variability
both are normal
variation = broad repertoire of behaviors for motor function
variability = capacity to select strategy that best suits situation
what are the phases of neuronal group selection theory
lots of variation in motor behavior; little adaptability
->->->
ability to select best motor strategy for task d/t active experience/trial & error; adaptable
according to neuronal group selection theory, what makes the broad repertoire of motor function behaviors more selective
interaction b/w genetics and experiences and innate abilities
what does the neuronal group selection theory say
ability to adapt to environment demands is shaped by the never-ending interaction b/w experience and genetic info
how can neuronal group selection theory be applied to working with children with movement dysfunction
need to provide opportunities for environment interaction and help them perceive the need for adaptability to achieve goal
what does the perception-action framework state
perception guides action & action “turns up” perceptual info
what are affordances as applicable to the perception-action framework
opportunities in environment to move
how does the perception-action framework define development
changes in bodies, perceptual skills, movement/action system
what is the process of development as defined by the perception- action framework
development -> changes in percepiton/action loop -> learning/development
what are 3 categories of early reflexes and reactions
- attitudinal/primitive reflexes
- righting reactions
- equilibrium & protective reactions
what does the hierarchal reflex theory of motor control say and how does this differ from contemporary theories
HIERARCHAL - CNS controls movement
- as matures goes from reflexive movement to more mature righting and equilibrium reactions for balance
CONTEMPORARY - CNS plays a role in development but not only main contributor
where are attitudinal/primitive reflexes mediated at
SC and brainstem
what are attitudinal/primitive reflexes
automatic, predicted motor pattern
not necessarily contributing to movement but first seen
where are righting reactions mediated at
midbrain
how are righting reactions used as an early strategy
response to mild perturbation
- initiates movement against gravity
where are equilibrium and protective reactions mediated at
cortex/higher centers
how are equilibrium and protective reactions utilized as an early strategy
response to mod-max perturbations
- keeps COG/COM w/i BOS
what are two attitudinal reflexes and what triggers them in general
- symmetric tonic neck (STNR)
- asymmetric tonic neck (ATNR)
reflexes changes body position based off where head is
what is the STNR and what triggers it
symmetric tonic neck reflex
triggered by head flex or ext
if head flex, UE flex and LE ext
if head ext, UE ext and LE flex
what is the ATNR and what triggers it
asymmetric tonic neck reflex
triggered by head rotation
head rotation will cause ipsi ext of UE and LE and contra flex of UE and LE
- fencing pose
what are 5 righting reactions
optical
labyrinthine
body on head
landau
neck on body
what is the optical righting reaction stimulated by
visual input
what is the labyrinthine righting reaction stimulated by
vestibular
what is the body on head righting reaction stimulated by
somatosensory
what is the landau righting reaction stimulated by
somatosensory
what is the neck on body righting reaction stimulated by
neck afferents
what do righting reflexes contribute to
postural control development
what does optical righting reaction look like
visual input from environment helps them adjust their head against gravity to be in line with the horizon
- ex: if holding sitting baby and tilt their body, their head will correct
- ex: visual input from a blanket or parent will help prone infant lift head up
describe the labrynthine righting reaction
when vision is occluded, vestib system is responsible for righting
- not having somatosensory info coming in from a surface
describe BOH righting reaction
receive somatosensory input from surface (ie table)
- ex: if moved (blind folded) prone infant to edge of table, would sense there isn’t more table and would lift head and upper trunk up
what is the testing position for the landau righting reaction
suspending them horizontally in air
what is a (+) Landau righting reaction
baby can hold superman position
- ext legs, head, trunk
what is the corresponding skill to a (+) Landau and when is this skill usually seen
prone ext
often seen when excited
what are the righting reactions NOB and BOB triggered by and what are their purposes
have to do w orientation of body to itself and getting body back into alignment
what is the NOB righting reaction
neck on body
- when passively rotating infant’s head, instead of triggering an automatic attitudinal response, see trunk roll like a log so that head, neck, trunk, and extremities all stay in alignment
what is the BOB righting reaction
body on body
- more mature reaction
- same realignment w more trunk rotation
what is the goal of equilibrium reactions
keep COM within BOS
what are 4 equilibrium reactions and when do you see them
- tilting - moving surface
- postural fixation - withstand external perturbations
- protective reactions - ant, lat, post
- staggering/stepping
how is transitional movement initiated
weight shift (WS)
what is the possible responses to a weight shift in a transitional movement
righting/equilibrium response
LOB
WS leads to postural response
what shapes the weight shift needed for a transitional movement and the response to that weight shift
individual, task, and environment
practice -> skill acquisition
what is the cephalocaudal direction of control
head control before trunk control
what is the progression of where postural control strategies/righting & equilibrium reactions are seen
prone/supine
then sitting
then standing
what is the progression of rolling and when in development (3)
~4mo - prone to supine
~6-8mo - supine to prone
~9mo - log roll -> segmental
what is the prone progression from birth to 10-13mo (5)
head life
prone on elbows (POE)
prone on hands (POH)
quadruped
creeping
when is static sitting achieved
~6-8mo
what are the 4 stages as static sitting develops
- no control of large sway
- attempts to initiate upright
- partial control w large range body sway
- ring sitting w arms propped in front, what happens if lift arms up - functional control w minimal sway
what is influencing the development of static sitting (4)
development of righting and equilibrium reactions
gains in strength
practice
opportunity
how does a child get from supine to stand early on and later (under the age of 2)
early on: roll to prone -> quadruped -> pull/push to stand
later: prone -> quadruped -> plantigrade -> stand
how does a child 2-3yo look going from supine to stand
modified roll & sit up -> stand
how does a child 4-5yo look going form supine to stand
symmetrical sit up pattern
what task is evidence of reactive and anticipatory postural adjustments once child can do it
pull to stand
when and where are reactive postural adjustments seen in infants and children (5)
7-8mo - ankle strategies in pull to stand
10-12mo - gross distal to prox motor coordination
3mo of walking - staggering/stepping responses
4-6yo - variability & adaptability of patterns
7-10yo - adult-like reactive adjustments
when and where are anticipatory postural adjustments seen in infants and children (4)
10-13mo - gastroc activity (to counteract motion of arms)
16-17mo - more consistent & temporally specific
3-5yo - variable APA (immature -> adult-like)
4-6yo - adult like APA
key ages of sensory integration for balance
4-6yo - transitional period for ability to resolve sensory conflicts using adult-like sensory integration strategies
adolescence - maturation of visual, somatosensory, vestib systems, & ability to solve sensory conflict
why are children 4-6yo usually clumsier than they have been
transitioning to use less vision for balance and more strategies for movement
how is visual input critical when it comes to balance
critical for calibrating and modulating b/w somatosensory and vestib input
what role does visual input play in postural reactions of infants
elicits organized postural reactions in standing in infants at an earlier age than somatosensory does in the presence of conflict
rely on visual system for sensory conflict
what role do vestib and somatosensory input play in postural control and balance
vestib - when vision is occluded, input on postural orientation
somatosensory - important for limb position and orientation
what are the 3 requirements for gait
- PROGRESSION: rhythmic stepping pattern
- STABILITY: strength + postural control
- ADAPTATION: to environmental changes
what are prenatal origins of gait (2)
~9wks gestation = isolated leg and arm movement
~16wks gestation = alternating leg movements
what is the sequence and order of limb movement and coordination prenatally
cephalocaudal sequence
- forelimbs -> hindlimbs
INTRAlimb -> INTERlimb coordination
why can’t newborns walk if there are prenatal origins to gait
immature postural control system and strength limitations against new role of gravity
what is the innate central pattern generator (CPG)
basic rhythm of step cycle
- seen in automatic (or neonatal) stepping reflex where feet move in reciprocal stepping pattern
where is the CPG located
below brainstem level
what is astasia-abasia
dancing feet
not reflexive movement of feet to take steps - much more inconsistent
when is neonatal stepping seen developmentally
appears newborn and “disappears” ab 2mo
according to the dynamic systems perspective, why does astasia-abasia disappear after 2mo
body build changes doesn’t match strength requirements
- changes in wt, length, mass
early maturation of descending pathways -> control of locomotor activity w/i 1st year
how is adaptation seen in gait
ability to step over, avoid obstacles
what is gait adaptation influenced by
reactive & proactive balance responses
what are 3 ways that gait adaptations are different in infants and young children compared to adults
- takes longer to change locomotor pattern prior to obstacle avoidance
- use vision to guide pattern change
- 1st use proactive movement of head and trunk to steer, then use reactive adjustments (step length, width) just before avoidance
what are 4 characteristics of the stance phase of gait in early walkers
- PF @IC
- flex knee
- absent push off motion
- force generation -> forward trunk lean
what position are the arms usually seen in early walkers and why
in high guard
- can help slow down if lot of momentum
what does the step width and temporal characteristics of gait look like in early walkers
wide step width
high cadence
low velocity
short swing phase d/t diminished SLS
what are 4 characteristics of the swing phase of gait in early walkers
dec DF
inc hip flex
pelvic tilt
hip ADD
what age is a child considered an early walker
~9-15mo
what are characteristics of the hip in gait for later walkers
dec pelvic tilt
ABD
ER
what age is a child to be considered a later walker
~2yo
what are 3 characteristics of gait in later walkers
- (+) knee flex wave
- push off by end of 2yo
- reciprocal arm swing, but UE post to trunk
what is a spatial characteristic of gait that will be different in later walkers than early walkers
narrower BOS in later walkers
how does gait develop from later walkers on
3yo - mature gait pattern
refinement by 7yo
how will gait change as it is refined from later walkers on (4)
SLS
step and stride side lengths
velocity
cadence
