05-02c: Development of Systems Across the Lifespan

Question 1

Lifespan Ages

Answer 1

• Newborn: Birth-1 month
• Infant: 1 month - 1 year
• Toddler: 1-2 years
• Child: 2-12 years
• Adolescent: 12-20 years
• Adult: 20-65 years
• Older Adult: 65+ years

Question 2

Skeletal Development - Newborn

Answer 2

Verterbral development begins in embryonic development

Question 3

Skeletal Development - Infant/Child

Answer 3

• Epiphysis is active site for new bone formation
• Epiphyseal plate is very thin and susceptible to compressive and tensile forces (avulsion Fx, greenstick Fx)
• Ambulation: Curvature of sacrum increases, ilium thickens, acetabular depth increases
• Femur of tibia goes from genu varum to genu valgum by 3 years old

Question 4

Skeletal Development - Adolescent

Answer 4

• Growth spurt girls: 12-13 yrs
• Growth spurt boys: 14-15 yrs
• Common stress Fx areas: Lumbar spine, tibia, fibula; Osgood Schlatters Disease (pain, inflammation, edema at tibial tuberosity - boys 10-15, girls 8-13)

Question 5

Skeletal Development - Adult

Answer 5

• Max bone mass: 20-30 yrs
• Balanced until 35-40yrs
• Women lose 1% per year prior to menopause, 2-4% yearly after
• Men lose .5% per year
• Intervertebral disk loses water (Nucleus pulposus is mainly affected; Annulus fibrosus becomes more fibrotic)
• Higher incident of disk-related pain between 25-45 yrs

Question 6

Skeletal Development - Older Adult

Answer 6

• Loss of bone mass leads to osteomalacia, osteopenia, osteoporosis
• Decreased activity further decreases bone mass

Question 7

Muscular Development - Infant to Adult

Answer 7

• In utero: Increase in both muscle fibers and size of individual fibers
• After birth: Growth of muscles comes mainly from increase in size of individual fibers
• At birth: Primarily fast twitch; slow twitch kicks in at 1-2 yrs

Question 8

Muscular Development - Older Adult

Answer 8

• Atrophy

- Directly related to activity of individual

Question 9

Strength - Infancy to Adolescence

Answer 9

• Linear increase from 6-18 yrs

- Boys have greater strength due to hormones, surpass girls around age 16

Question 10

Strength - Adulthood

Answer 10

• Maximum strength in males: 30-35 yrs
• Muscle mass declines after 45 yrs (1% per year)
• Older adults can maintain or even increase skeletal muscle mass and thus strength with resistance exercises (into 80s, 90s)

Question 11

Cardiovascular - Prenatal

Answer 11

• Blood circulation begins at 3 weeks gestation

- Heart develops as recognizable structure between 20-50 days of gestation

Question 12

Cardiovascular - Infancy and Childhood

Answer 12

• Newborn heart lis horizontal in chest cavity (as lungs expand and cavity grows, becomes more vertical)
• R/L ventricles are equally thick; as L ventricle begins pumping, wall size increases and becomes twice as thick by adulthood

Question 13

Cardiovascular - Adolescence

Answer 13

• Amount of muscle in heart increases

- Increased BP; Decreased HR

Question 14

Cardiovascular - Adulthood and Older Adult

Answer 14

• Heart size and weight continues to increase in adulthood due to fat deposit
• Valves thicken and calcify with aging
• Aging changes seen in coronary arteries at 20 yrs, rest of arterial system after 40 yrs

Question 15

Heart Rates

Answer 15

• Newborn: 120-140 bpm
• 1 yo: 100 bpm
• 6 yo: 80 bpm
• 10 yo - Adult: 70 bpm

Question 16

Blood Pressures (Systolic)

Answer 16

• Newborn: 40-75 mmHg
• 2 yo: 83-88 mmHg
• 5 yo: 95 mmHg
• Diastolic is between 50-55 mmHg

Question 17

Pulmonary - Child

Answer 17

• Children under 5 yo have larger number of small airways; problems because 1) increase in airflow resistance = increase work at breathing, 2) easily obstructed by foreign onjects
• Alveoli and bronchioles are weaker and less efficient
• Smooth muscle in bronchioles does not develop until 3-4 yo

Question 18

Pulmonary - Older Adult

Answer 18

• Thorax shortends vertically and larger in A<>P direction due to degeneration of disc height
• Lungs, alveoli, and alveolar ducts get larger
• Respiratory muscles become less efficient

Question 19

Nervous - Infant and Child

Answer 19

• Critical brain growth occurs between 3-10 months and between 15-24 months
• Brain weight doubles by 6 months (early myelination = why newborns sleep most of the time)
• First 2 months after birth = CNS organization
• Social behavior begins at 2 months with social smile
• 24 hr biological clock established between 2-4 months (regards day and night)

Question 20

Nervous - Child and Adolescent

Answer 20

• Brain growth spurts at 6-8 yo, 10-12 yo, 18 yo
• Develop functional skills such as throwing, jumping, catching, balancing at 3-6 yo
• Skills refined at 6-10 yo

Question 21

Nervous - Adult

Answer 21

• Brain weight declines at 20 yo
• CNS changes with age, affects frontal/temporal lobes
• Memory declines at 30 yo

Question 22

Nervous - Older adult

Answer 22

Loss of neuron size and aging = explanation for forgetfulness in older adults

Question 23

Sensory - Infant and Early Childhood Touch

Answer 23

• First response to touch - diffuse (arms and legs move around randomly
• Rooting reflex until 3 months
• Touch localized at 7-9 months, can’t tell where touched
• Specific localization demonstrated 12-16 months; toddler can identify place where touched and rub area or push stimulus away
• Doll eye phenomenon - newborn held in supine suspended and moved horizontally; eyes appear to go opposite direction of the body

Question 24

Sensory - Infant and Early Childhood Vision

Answer 24

• Newborn vision is poor
• Lateral approach, unable to hold head in midline until 4 months
• Infant sees b/w until 4 months (full color present)
• Visual alignment 3-6 months, due to head control and ability to fix on objects

Question 25

Sensory - Infant and Early Childhood Sound

Answer 25

- 1 month: Auditory system myelinated - 3 months: head turns to locate sounds - 4 months: Infant begins to babble in vocal play as they respond to new sounds - 1 yo: words being pronounced

Question 26

Sensory - Infant and Early Childhood Taste/Smell

Answer 26

- Functional at birth, connect to feeding reflexes | - 5 day old infant can orient to mother's breast pad based on odor

Question 27

Sensory - Child and Adolescence

Answer 27

- 3 yo: Visual closure (ability to discern a shape when seeing only part of it) - 5 yo: Visual pursuit (ability to track moving objects) - 11 yo: Perceptual judgments based on size are matured - 12 yo: Depth perception fully achieved

Question 28

Sensory - Adults and older adults

Answer 28

- Dizziness and vertigo common after 50 yo - Presbyopia: Diminished ability to focus clearly at normal reading distances - Hearing declines due to loss of sensory cells in the inner ear

Question 29

Exercise Training - Childhood

Answer 29

- Children don't respond well to CV training - Children sweat less than adults, making it difficult to dissipate heat - Don't focus only on strengthening and CV endurance, add coordination and balance exercises, functional exercises

Question 30

Exercise Training - Older Adult

Answer 30

- Focus on low intensity strengthening - Focus on functional tasks/ADLs, balance exercises, and gait training - Include warm up and cool down