PT 705 Developmental sequence and reflexes

Gestational age (GA)

• Last menstrual period (LMP)- time from the first day of the last menstruation

Postconceptual age/ embryonic age

• Time from the moment of conception; age of developing fetus (2 weeks less than GA)

Corrected (adjusted) age

• Subtract # of weeks premature from chronological age

• Full term: 37-42 weeks (40 weeks for calculation)

• Premature: a birth that takes place < 37 weeks GA

Gestational break down

• Germinal- 0-2 weeks

• Embryonic- 3-8 weeks → Teratogens most effective here

• Fetal- 9 weeks → birth

Teratogens → impact on development

• Start w/ 3-5% chance to develop fetal birth defects

• Drug, environmental substance or maternal condition that is capable of interfering w/ the development of the fetus, and typically results in birth defects

• Examples: meds, maternal infections/ disorders, chemicals, substances

Prevention of birth defects

• not all can be prevented

• early and regular prenatal appointments

• 400 micrograms of folic acid daily, starting at least a month before getting pregnant

• Do not smoke, drink alcohol, or use recreational drugs

• Discuss medications w/ MD

• Prevent illness during pregnancy

  • Flu shot, good hand hygiene

Embryonic (post-conceptual) development 0-3

• Development continues in cephalocaudal direction

• Hyperplasia (increase in # of cells) and differentiation (cells become specialized)

• Week 3

  • organization of embryonic disc into:

    • Endoderm: digestive tract

    • Mesoderm: muscles, skeleton, circulation

    • Ectoderm: skin & nervous system (NS)

  • Exposure to teratogens is most dangerous

Embryonic Week 4

• Heartbeat present

• Neural tube closure

• limb buds form

Embryonic week 6

• placental circulation functional through umbilical cord

• Brain division and cerebral hemispheres

• CV system functioning

• eyes w/ eyelids

• Vertebrae begins to form

Embryonic week 8- humanization

• Eyes, ears, nose, mouth, fingers, toes, heart formed

• embryo looks like a human and all tissues formed

closure of neural tube disrupted →

• anencephaly

• craniorachischisis

• open spina bifida

• iniencephaly

• encephalocele

• closed spina bifida

Fetal development general (9 wks- birth)

• 9 weeks, now called a fetus

• teratogen exposure less likely to cause birth defects

  • could cause fetal growth restrictions or placental distress, infections/ dehydration of mom

• rapid proliferation and hyperplasia

• organ and tissue differentiation continue

• bones continue to ossify and remodel

• appearance becomes more proportional

Fetal development 9-16 weeks

• cartilaginous skeleton formed

• swallowing emerges

• external genitalia visible by 12 weeks

• eyes move

• developmental reflexes strengthen

Fetal development 17-20 weeks

• mother can feel fetal mvmt toward the end of this stage

• skin covered in lanugo: layer of fine hair

• Adipose tissue

• Lung maturation continues

• Diagnosis of congenital heart defects (heart size of thumbnail)

• Not able to survive if born before 21 weeks

Fetal development 21-29 weeks

• fetus is viable at 23 weeks if born prematurely (NICU)

• Accelerated weight gain

• Ongoing lung development, begins to produce surfactant

• Eyes fully developed by week 25, REM

• by week 29:

  • All external characteristics of a full-term infant by week 29

    • hair, nails

  • all neonatal reflexes present

  • Able to cry audibly

Fetal development 30-38 weeks

• Weight gain continues

  • Fat accumulation for insulation over last week

• Thermal regulation established by 32 weeks

• Fetal movements decreased

  • decreased space

  • maturation/ stability

Birth

• head down (vertex), face down

• Head should be slightly smaller than pelvic outlet

• Entry into the world can be traumatic experience

• Should breathe on their own w/in a few seconds

• Shift from fetal circulation to adult circulation

• now ready to participate in life

Breech birth

• turned in some way not head down

APGAR Score 0

• Appearance- pale/ blue

• Pulse- no pulse

• Grimace- no response to stimulation

• Activity- no movement

• Respiration- no breathing

APGAR Score 1

• Appearance- Extremities blue

• Pulse- < 100 BPM

• Grimace- Grimaces or weak cry

• Activity- arms, legs flexed

• Respiration- slow/ irregular

APGAR Score 2

• Appearance- Pink

• Pulse- > 100 bpm

• Grimace- cries and pulls away

• Activity- active movement

• Respiration- strong cry

APGAR testing times

• 1 min

  • 7-10: routine care

  • 4-6: some assistance for breathing may be required

  • < 4: lifesaving measures

• 5 min

  • 7-10: normal

  • <7: ongoing monitoring every 5 min up to 20

Birth weight

• Normal birth weight

  • >5 lbs 8 oz, < 8 lbs 14 oz

• Small for gestational age (SGA) < 5lbs, 8 oz (2500g)

  • Low birth weight (LBW) 1500g- 2500g

  • Very low birth weight (VLBW) 1000- <1500g

  • Extremely low birth weight (ELBW) <1000g

Fetal Alchohol syndrome

• estimated prevalence is 1% → #1 cause of intellectual disability in the world

• Caused by parental exposure to alcohol

  • enters baby’s bloodstream through placenta

• neuromuscular impairments

  • fine and visual motor deficits

  • impaired balance, coordination, and motor development

• Musculoskeletal impairments

  • facial: smooth philtrum, thin upper lip, broad nose

  • poor growth, microcephaly

  • abnormal joint position or function

  • short stature

• cardiopulmonary impairments

  • heart defects

• behavioral/ cognitive

  • hyperactivity

  • poor memory and attention (intellectual disability)

FAS Infants

• low birth weight

• irritability

• sensory sensitivity to light

• poor sucking

• global developmental delay

• poor sleep-wake cycles

• increased ear infections

FAS toddlers

• poor memory capability

• hyperactivity

• impulsive/ lack of fear

• lack of sense of boundaries

FAS across the lifespan

• school age

  • short attention span

  • poor coordination

  • difficulty w/ both fine and gross motor skills

  • learning disabilities

• Adolescents

  • trouble keeping up w/ school

  • Low self-esteem from recognizing that they are different from peers

  • poor impulse control

• Adults

  • poor life skills

Neonatal abstinence syndrome (NAS)

• behaviors seen in newborn following abrupt termination of gestational exposure to substances

  • opioids

  • benzodiazepines

  • alcohol

  • antidepressants

  • antipsychotics

  • heroin

  • methadone

Neonatal abstinence syndrome- Tx

• Tx:

  • gradual wean off substances

  • replace w/ morphine, methadone

NAS across the lifespan

• Research is ongoing to look at the long-term impact

• signs of withdrawal will decrease over length of NICU stay

• Some potential impairments that may persist

  • vision problems

  • motor impairments

  • behavioral/ cognitive problems

  • sleep disturbances

microcphaly

• Small head and brain, often intellectual disability

Anencephaly

• absence of the cranial vault, failure of rostral neural tube to close, resulting in an absence of the cerebral hemispheres → incompatible with life

Encephalocele

• is a sac-like protrusion or projection of the brain and the membranes that cover it through an opening in the skull

Omphalocele

• herniation of the intra-abdominal contents into the base of the umbilical cord- requires progressive compression of abdominal contents and skin closure

General principles of motor development -Physiologic flexion

• Physiologic flexion- natural posture of a newborn (fetal position) w/ flexed arms and legs held close to the body

General principles of motor development- Cephalocaudal & proximodistal

• Cephalocaudal & proximodistal- develop head and UE control prior to trunk and LE, midline stability first w/ gain in distal control

General principles of motor development- Progress from sagittal → frontal → transverse

• Progress from sagittal → frontal → transverse

  • lifting head, kicking legs

  • reaching sideways or across midline, lateral weight shifting

  • Rotating body parts- head, rolling, reach for object behind

General principles of motor development- Extension before flexion

• Extension before flexion

  • develop strength in extensors first before flexors

  • overcome physiologic flexion

  • develop against gravity (cervical extension, push up on arms, kick less)

Neonate: physiologic flexion

• key feature of this period is physiologic flexion

  • ankles, knees, hips, elbows

  • assessed by flexor recoil response (sometimes called “traction response”)

  • Seen in prone, supine and side lying

  • easily brings hand to mouth

• Reflexes present at birth

  • all accept Landau & STNR

Pathway 0-2 months motor milestones

• While lying on tummy, lifts and holds head up

• Able to move fists from closed to open

• Moves legs and arms off of surface when excited

Neonate: 0-1 month Prone

• hip flexion leads to weight shifted onto the face and upper chest

• able to lift and turn head to clear airway → shifts weight to shoulder

• Lifts head when held prone to chest

Neonate: 0-1 month supine

• Kicks LE (reciprocal and symmetrical patterns)

• No active cervical flexion

• Unable to maintain head in midline but can bring it briefly to center before falling to either side (initially)

• Full head lag on pull to sit

Neonate: 0-1 month supported sitting

• supported sitting

  • lack of trunk control, no spinal extension

  • smooth, rounded back

  • head forward and flexed

Neonate: 0-1 month standing

• Standing

  • positive support

  • spontaneous stepping

Neonate: 0-1 month other

• Other

  • vision: minimal

  • Faces

  • black/ white/ red

• hands tend to be fisted

• jerky uncoordinated limb mvmts

Pathways 2-4 months motor milestones

• While lying on tummy, supports self on arms

• brings hands to mouth

• stands w/ support

2-3 months prone

• weight-bearing through the forearms

• progressive c-spine extension up to 90 degrees by 3 months

• SIDs risk: back is best- however delays prone skills

2-3 months supine

• head in midline

• increased frequency of kicking

• more reciprocal kicking by 3 months

• ATNR most prominent at 2 months, resolving by 3 months

• Bringing hands to mouth

2-3 months supported sitting

• improved head control, longer periods maintaining upright position

  • Many will have independent head control by month 3

    • active head rotation, flex/ ext

  • Most will still have head bob

  • Most fatigue easily

• Require trunk support to maintain

• C- curve posture, cervical extension to neutral by 3 months

2-3 months Standing

• Standing

  • progressively poor WB as positive support reflex goes away

  • Full trunk support

2-3 months mobility

• Mobility

  • may roll from prone to supine

  • minimal head lag w/ pull to sit by 3 months

2-3 months other

• Other

  • Vision: continued preference for faces

    • developing vision for colors

    • Improving distance vision

    • Visually tracks w/ cervical rot. 180 degrees

  • Listens to voices

  • smiles

  • now able to be held in a variety of positions

Pathways 4-6 month motor milestones

• keeps head upright when in supported positions

• reaches for toys while on tummy

• rolls from back to/ from tummy

• uses hands to support self while sitting (tripod position)

• while supine, reaches both hands to play w/ feet

• while prone, pushes up on straight arms

4-5 months prone

• able to push up through extended UE

  • WB shifts to pelvis

• Many will start to weight shift and pivot in prone to reach and access toys

• Increased time is spent in prone

4-5 months supine

• hands to feet and feet to mouth

• hold toys w/ both hands

• hands to midline

4-5 months sitting

• good head control

  • able to Rot., flex/ extend head

• able to sit w/ UE propped anterior

• Starting to be able to sit w/ lateral UE support to reach for toys

• Brief sitting w/o UE support w/ frequent lob

4-5 months other standing

• may accept weight through LE w/ trunk support

4-5 months other mobility

• Mobility

  • rolling from supine <> prone

  • no head lag w/ pull to sit

  • may be starting to push back in prone

  • some may be transitioning into quadped <> prone

  • pivoting in prone

4-5 months other other

• Other

  • laughs

  • Smile at themselves in the mirror

  • turns toward voice/ sound

Container babies

• Don’t put your babies in containers, it fucks with their posture

pathways motor milestones 6-9 months

• Sits w/o support

• sits and reaches for toys w/o falling

• moves from prone or supine into sitting

• begins crawling and creeping

• While in supine, transfers toy from one hand to the other

• Picks up small objects w/ thumbs and fingers (rakes)

• Imitates others in sitting and play

6-7 months quadruped

• maintains weight on single UE in prone w/ lateral weight-shifting to allow for reach for play/ obtain toys

• Rocking in quadruped

6-7 months supine

• lifts head against gravity

• attempts to sit up successfully

  • demonstrates abdominal activation

• Minimal time spent in supine

6-7 months sitting

• independent

• Starting to be able to perform lateral and anterior weight shifting w/o LOB

• Anterior balance reactions present

6-7 months standing

• Full support of body weight w/ trunk support

• May start bouncing in supported standing

6-7 months mobility

• army crawling backwards

• transitioning from sit <> prone

• Proficient roller, frequently used for mobility

• Neck and core activation w/ pull <> sit

6-7 months other

• very curious about surrounding environment

• Love mirrors and familiar people

• Starting to babble

• Responds to name

• Passes objects/ toys b/t hands

8-9 months prone/ quadped

• rarely stays in prone, transitions to quadped

8-9 months Supine

• very rarely in supine

8-9 months sitting

• Active playing in sitting, including reaching outside BOS

• Anterior and lateral protective reactions are present (7-8 months)

• posterior protective reactions emerging (9-12 months)

8-9 months Standing

• stands w/ UE support at a surface

• Stands w/ hands-held assist

• frequent bouncing

8-9 months mobility

• independent transitions from sit <> quadped

• Pulling to stand at a stable surface/ furniture

• Army crawling forwards

  • some are starting to quadped creep

• Some are starting to cruise on stable surface furniture w/ BUE support

8-9 months others

• Takes objects out of containers

• Shouts/ vocalizes for attention

• Responds to “no” most of the time

• Very active and wiggly

• Start to wave goodbye

• Prefer to be w/ people

Pathways 10-12 month motor milestones

• Release objects into a container w/ a large opening

• Moves in/out of position to explore and get toys

• Regularly moves w/ alternate leg and arm mvmt (crawling/ creeping)

• Pulls to stand and cruises along furniture

• Uses thumb and index finger to pick up tiny objects

10-11 months quadped

• able to maintain 2-3 point limb contact for play

10- 11 months standing

• may stand briefly w/o UE support

• Stands frequently w/ single UE support

10- 11 months mobility

• pull to stand through HL at a surface

• pivot in sitting, may perform seated scooting

• cruising at a surface

  • may be able to take a step to bridge the gap in furniture

• Walks w/ handheld assist, may take steps w/ single hand assist

• Most are creeping as main mode of mobility

• Creeps in variety of patterns including bear crawl

10- 11 months other

• may have a fear of strangers

• performs for attention

• plays patty-cake and peak-a-boo

• making repetitive consonants

• posterior protective reactions present (9-12 months)

Crawling v. creeping (7-9 months)

• crawling = army crawl

• creeping = quadped

floor transfers (12 months)

• sitting on floor <> standing

• True sit-up at age 5-6

Pull to stand (10-12 months)

• UE on surface kneeling/ sitting to standing at surface

Cruising (10-12 months)

• Side stepping holding onto a surface

Pathways 12-15 months motor milestones

• clap hands

• stands alone and takes several independent steps

12 months mobility

• stands through quadped w/o a surface

• lowers controlled from standing to sitting

• controlled squat

12 months sitting

• large variety of sitting and kneeling positions

  • side sit, side HK, long sit, low kneel, high kneel

  • posterior balance reactions emerging or present

12 months ambulation

• most will develop ability to ambulate w/o support

• Initially walking w/ high guard UE position, wide BOS

12 months Other

• frequently play in a deep squat position

• follow simple commands

• able to roll a ball

• points to 3 body parts

• vocalizes w/ intent

Pathways 15-18 months

• climbs on low furniture

• squats to pick up toy

• walks independently and seldom falls

• Cognition- understand names of things (dog), follow simple directions (give me the ball), ask for help

12- 18 months

• maintain a deep squat for play

• squat to stand to pick up toys

• climbs up stairs all fours

• able to stop and start when walking

• throwing balls

• may attempt kicking

  • walks into ball

• pulls toys

• Up until this point (3 months- 18 months) babies will put everything in their mouths)

Pathways 18-24 months

• Goes up/ down stairs w/ support: step to

• Begins to kick or throw ball

• runs- walks w/ increased cadence

• stands on tiptoes, starting to work on jumping

• when walking, able to pull toys behind them

• Cognition- copies you doing chores, attention to read a few pages of a book; plays w/ toys in a simple way

18- 24 months

• walks up/down the stairs w/ one band-held, step to pattern

• Begins to increase cadence towards running

• climbs on/off furniture independently

• continues to work on throwing

• continues to work on kicking

• starts to work on jumping (steps forward)

24-36 months

• Runs: starts to see “flight” phase

• walks up/down stairs independently

  • reciprocal and holding railing

• kicks a stationalry ball

• walks backwards

• single leg stance x 2 sec

• twist things w/ hands (water cap, door knob)

• eats w/ spoon

• overhand throw

2.5- 3 y/o

• 2-foot jump: both feet leave the ground

  • jumping down, land on one foot first

• able to string large beads onto string

• catches a large ball-traps against chest

• enjoying playing games (hide/ tag)

• Cognitive: notices when others are hurt/ see response, 2 or more words t/g; points to body parts, can nod yes or blow kiss; pretends to follow simple routines, problem solving; 2-step command; learning colors

3 years

• able to walk on tip toes/ heels

• briefly able to tandem walk (begin here)

• Single limb stance: 3 sec

• reciprocal stair climbing (w/o rail)

• jumps down feet together (knees straight)

• Hops on one foot 1-2x/ row

• Throws/ catches a large ball

  • under and overhand

  • arms forward and supinated (catch away from body)

  • hits via T-ball

• Rides a tricycle

• somersaults (struggles w/ chin tuck)

• Cognitive: joins into play w/ other children; 50% of language is understood; avoids touching hot objects if warned

4 years

• gallops

  • asymmetrical locomotion

• Hops on one foot: 4-6x/ row

  • jumps down, feet together, knees bent

• Single limb stance: 4-8 seconds

• Able to make quick turns when running

• Cognitive: comforts others who are hurt (hug a friend); pretends; avoids danger at playground- jumping from high surfaces; sentences in 4 or more words; draws a person w/ 3 or more body parts, change behavior based on where they are

5 years

• hops on one foot > 10 times in a row

• tries jump rope, roller skates. >36’ fwd jump

• very active climber

• bicycle w/ training wheels

• can throw and hit a target w/ a ball from 10 feet away

• can walk on a balance beam

• skips

• true sit up (5-6 yrs)

• Cognition: follows rules or takes turns; simple chores; can answer questions about a story; converses; simple rhymes; counts to 10; starts using words accurately about time- yesterday/ morning; starts writing name

6 years

• single limb stance: > 10 sec, EO/ EC

• Bounce and catch a ball

• jumps rope well

• active play on playground

• hopscotch

• rides a bike w/o training wheels

7-10 years

• bat/ pitch a ball

• body mvmts become more rhythmic and graceful

• interested in lifting things

• play hard

Progression of locomotion

Crawling → walking → running → stair climbing

How locomotion develops

• CNS maturation develops motor patterns for locomotion

• Physical development drives changes in motor patterns

  • Strength, balance, coordination, body/ limb size

• Biomechanical factors

  • Step length, step width, stride length, velocity, cadence

• Experience & practice