Growth Flashcards
What are the cellular processes to increase size?
Hyperplasia – increase cell number
Hypertrophy – increase cell size
Accretion – increase intercellular substance
True or false: lymphoid tissue doubles the amount seen in adult?
True
T or F: most of the neural tissue growth takes place in adulthood?
False: childhood
T or F: fetal growth rate is the fastest than any other periods in a human lifetime?
True
What is the childhood rate of height growth per year?
6 cm
Why are females on average shorter than males?
Pubertal linear velocities:
- occur earlier
- have a lower magnitude
- shorter duration of pubertal growth
True or False: puberty contributes most to the final adult height?
False: infantile and childhood (puberty 10-15%)
What happens to arm span in relation to height throughout lifespan?
pre-puberty: arm span less than height
post-puberty: more than height
At approximately what age does the upper segment to lower is lower?
from age 7 and beyond
If the upper to lower segment ratio is higher than 1 for a 7 yrs old or older, what would this mean?
genetic syndrome
bone dysplagia
What two types of growth charts are used for 2 yrs or less?
head-circumference-for-age
weight-for-length
WHO growth charts are made from what?
WHO :
growth standards
growth reference
What age dictates at which percentile rate a child will grow?
2 years of age (continue at the same growth channel until puberty and should not deviate from growth channel)
What color is bone and cartilage on x-ray?
bone - white
cartilage - black
What is the end of the bone called?
epiphysis
True or false: the growth plate produces the metaphysis
False: it is the epiphysis
What is the material that makes up the growth plate prior to adulthood?
cartilage
True or False: Maturation of growth can be reflected in bone age
True
What does bone represent and reflect?
- represents secondary ossification
- reflects physiologic growth and maturity
What are the broad determinants of growth?
- genetics
- nutrition
- illness/health status (chronic anemia)
- environment (sleep, exercise, seasonality, psychological)
- hormones (proliferation and differentiation of chondrocytes) - insulin, GF, IGF-1, thyroid, estrogen
- -> glucocorticoids stunts growth
What is failure to thrive?
Body weight or rate of weight gain much less than expected compared to children of similar age and sex
- usually thin for their length (length and head circum. less affected than length)
What are causes of failure to thrive?
- inadequate intake (usually cause of very young)
- inability to use
- excessive utilization of energy
What is short stature?
Lower than 3rd% (-2 SD) for age and sex
When is short stature pathological?
Linear velocity lower than -2 SD for age
Crossing down more than 2 major growth channel lines
Projected height is lower than -2 SD for mid-parental target height
What are causes of short stature?
Improper Growth Measurements
Normal variants:
Familial short stature (FSS)
Constitutional delay of growth and puberty (CDGP)
Pathologic causes:
Endocrinopathy (ie. hypothyroidism, growth hormone deficiencies, glucocorticoid excess ie. cushings)
Systemic Illness or Subclinical Illness (or meds)
Genetic Syndrome
Bony Dysplasias
Intrauterine Growth Retardation (IUGR) (ie. less than 10 percentile that do not catch up by 2 yrs)
Psychosocial deprivation (Kaspar Hauser syndrome)
What is the difference between FSS and CDGP?
for FSS: Parents are short Puberty is not delayed Typically no bone age delay Height-for-age trajectory approximates the mid-parental target height (height-for-bone age in CDGP)
T or F: for endocrinopathies both weight and height velocities slow down?
False - only height, weight should be unaffected for then most part (unlike systemic disorders)
What is tall stature and when is it pathological?
Higher than 97th% (+2 SD) for age and sex.
Is potentially pathologic if:
Linear velocity higher than +2 SD for age (crossing up percentiles)
Projected height is higher than +2 SD for mid-parental target height
Causes of Tall Stature:
Normal Variants:
Familial Tall Stature
Constitutional
Obesity
Pathologic causes: Endocrinopathy Precocious Puberty GH excess (rare) Hyperthyroidism Genetic syndromes Marfan syndrome Sotos syndrome
True or False: bone age is greater than chronological age for precocious puberty
True
