SOM Unit 2 PDF: Development of Movement

Here is the text from the image converted to markdown format: # SOM-Unit 2: Development of Movement ## TYPICAL DEVELOPMENT PROGRESSION * **Cephalocaudal progression**: head learns how to lift against the ground before the pelvis into a quadruped position * **Gross motor before fine motor**: k...

Here is the text from the image converted to markdown format: # SOM-Unit 2: Development of Movement ## TYPICAL DEVELOPMENT PROGRESSION * **Cephalocaudal progression**: head learns how to lift against the ground before the pelvis into a quadruped position * **Gross motor before fine motor**: kids are able to do big gross movements first (full body movement: arms/legs) -> over time it gets to the grasp movement (to pick up a cheerio & put it in your mouth) * **Proximal to distal pattern**: proximal musculature gains control before the distal musculature (kinda goes with the gross motor before fine motor) * **Reflexive to volitional movement:** ability to take over with voluntary movement as you age - as individual task, & environment play a role in function * **Infant reflexes to postural reactions**: many are controlled at the level of the brain stem -> toward volitional control - what takes over this are the higher order postural reactions ### PRIMITIVE (INFANT) REFLEXES * movement linked to reflexes for the first months of life * reflexive movements occur quickly (stimulus-response) * involve single muscle or specific group of muscles * are extinguished over the first year of life there's a dynamic interplay between reflexive activity slowly dampening individual control to help volition control take over reflexive/spontaneous movements resembles reaching & spontaneous kicking resembles walking ### POSTURAL REACTIONS (RESPONSES) * begin around 2-3 months of age * continue throughout life * helps maintain upright posture in changing environments Ranges for Typical Infant Developmental Milestone (AIMS & WHO 2020 Data) sitting: 4-7 months rolling: 5-7 months crawling (belly)/creeping(quad): 8-10 months pull to stand: 9-10 months walking: 12-18 months gallop/skip: 3-5 years ## DEVELOPMENTAL POSTURAL REACTIONS * **RIGHTING REACTIONS ORIENT THE HEAD** in space to keep head upright in midline * Optical righting: in space using **VISUAL** output * Labyrinthine righting: to an upright position using **VESTIBULAR** input * Body on head righting: to an upright position using **PROPRIOCEPTIVE** input * **PROTECTIVE REACTIONS** * extension of the extremities in effort to protect self from injury when falling forward, sideways, backward * AKA Parachute response: allows the arms to catch self to protect the head when laying prone off a surface or when tipped down head first (AKA Forward protective extension) * Backward protective reaction: extending the arms backward to protect against backward fall * **EQUILIBRIUM REACTIONS** * when the body is displaced off balance, creating a change of posture, causing the trunk and extremities to move in the direction opposite the force that created the loss of balance * orients whole body to midline and upright position against gravity ## IMPACT OF AGING ON POSTURAL CONTROL * **Factors** * individual system changes * tasks change * environments more varied * **Dependent upon individual variability** * sedentary vs active * ability to perform tasks * history of falls * **Internal (primary) factors** * genetics, family history accounts for 20% of aging * **External (secondary) factors** * lifestyle & environmental accounts for 80% of aging as PTs we can help prevent falls through screenings,. home safety ex's, & wellness/balance training! :) ### NEUROLOGICAL AFFECT ON POSTURAL CONTROL * **SPINAL CORD**: sensory input drives motor output * **BRAINSTEM**: helps with postural adjustments and anticipatory control * **BASAL GANGLIA CEREBELLUM**: help with balance adjusting in changing tasks and environment ### SENSORY INVOLVEMENT * **VISUAL**: sway increases with eyes closed or with conflicting visual input * **SOMATOSENSORY**: input from tactile and joint mechano/proprioceptor receptors help the body to know "where it is in space", with changing positions and effects of gravity * **VESTIBULAR**: is activated in loss of balance as it responds to changing position of the head WHAT CHANGES? ### SENSORY SYSTEM declining vestibular, visual, and somatosensory functioning may lead to decreased postural control and may increase risk of falling * Spinal Posture: decreased spinal flexibility and muscle strength lead to increased cervical curve, thoracic kyphosis, & flattened lumber spine leading to forward weight shift approaching the limit of stability * Muscle Strength: strength peaks in 20s/30s then begins to decline as one ages Sarcopenia development is associated with loss of function & decreased postural control muscles used for running/ jumping atrophy faster than muscles for walking/daily tasks ### Nervous System The loss of neurons, dendrites, synapses, neurotransmitters, & myelin in aging causing slower processing speed and delayed postural reactions -> steady state, reactive, and anticipatory postural reactions are affected ## FOUR TYPES OF POSTURAL CONTROL * **STATIC CONTROL** * little conscious muscle activation * "postural tone" activation by antigravity postural muscles keeps one upright and in good alignment * erector spinae, abdominals, TFL, gastrocnemius, tibialis anterior * **ANTICIPATORY/ADAPTIVE CONTROL** * FEEDFORWARD POSTURAL STRATEGIES * Postural muscles activated in advance based off what the person anticipates. This is called central set or preprogram ant/post begins distal @ ankle which is opposite of med/lat ### STRATEGIES WHEN LOSS OF POSTURAL CONTROL * **POSTURAL SWAY** small, slow moments of the body when we are standing still NOT considered loss of balance IS part of static control * Reactive/Adaptive Control * FEEDBACK POSTURAL CONTROL * MUSCLE SYNERGIES: used to regain postural control in ant/post loss of balance * ankle strategy: to slower+smaller perturbations * hip strategy: faster+larger perturbations * stepping strategy: change in support surface when ankle & hip strategies aren't enough to maintain BOS * reach & grasp: may be used as alternative strategy instead of stepping strategy for medial/lateral loss of balance * mostly hip/trunk strategies * lateral movement @ pelvis: adduction of one leg, abduction the other * head movement starts the correction, followed by the rest of the body (cephalocaudal) I hope this helps