Growth and development Flashcards
What percentage of eventual height does the foetal phase of growth contribute to?
30%
What percentage of final height does the infantile phase of growth contribute?
15%
What percentage of final height does the childhood phase of growth contribute to?
40%
What percentage of final height does the pubertal growth spurt contribute?
15%
What are the main determinant of childhood growth phase?
- Genetics
- GH - acting to produce IGF-1 at the epiphyses.
- Thyroid Hormone
- General health
What is infantile growth largely dependent on?
- Good nutrition
- Good health
- Thyroid hormones
What is size at birth determined by?
- Size of mother
- Placental nutrient supply - modulates growth factors IGF-2, human placental lactogen, insulin
What do sex hormones cause in terms of bone growth?
Fusion of the epiphyseal growth plates
How much do preterm infants grow by per week?
0.8-1cm per week
What is the growth rate in the first 2 months of life?
2.5 cm per month
How much do children grow in length within the first year?
Approximately 25 cm
What is the average growth velocity in childhood?
4-8 cm per year
What are the different categoris of pubertal development used in the tanner staging of puberty?
- Female breast changes
- Pubic hair changes - male and female
- Male genital changes
What are the 5 stages of female breast change?
- B1 - prepubertal
- B2 - breast bud
- B3 - juvenile smooth contour
- B4 - areola and papilla project above breast
- B5 - Adult
What are the 5 stages of pubic hair change in males and females?
- PH1 - Pre-adolescent - no hair
- PH2 - Sparse, pigmented, long, straight, mainly along labia and base of penis
- PH3 - dark, coarser, curlier
- PH4 - filling out towards adult
- PH5 - adult distribution
What are the 5 stages of male genitalia development in the tanner staging of puberty?
- G1 - preadolescent
- G2 - lengthening of the penis
- G3 - Further growth in length and circumference
- G4 - Development of the glans, darkening of scrotal skin
- G5 - adult genetalia
What are the features of puberty in a female?
- Breast development
- Pubic hair growth
- Menarche - 2.5 years after start of puberty
What does menarche indicate in terms of growth?
Growth is coming to an end - only around 5cm growth left
What are features of puberty in males?
- Testicular enlargement - first clinical sign of puberty
- Pubic hair growth
- Rapid height growth
What occurs during puberty in both sexes?
- Acne
- Axillary hair
- Body odour
- Mood changes
If a child is within 1/4 of a centile line, how is that centile described?
On the X centile
In terms of standard deviations, how many standard deviations is the 0.4th centile away from the mean?
-2.6 SD
How many SD’s is the 2nd centile away from the mean?
- 2 SD
How many SDs is the 9th centile away from the mean?
-1.3 SD
How many SD’s away from the mean is the 25th centile?
-0.66 SDs
When assessing growth, what would you ask about in the history?
- Birth weight and gestation
- PMH
- Family history/social history/schooling
- Systematic enquiry
- Dysmorphic features
- Systemic examination
- Pubertal staging
When evaluating a childs growth, what would you do?
- Height/ length/ weight
- Growth Charts and plotting
- MPH and Target centiles
- Growth velocity
- Bone age
- Pubertal assessment
What would you use to calculate potential height
Mean parental height
Boys = (Father +mother)/2 + 7cm
Girls = (Father +mother)/2 - 7cm
how could you determine skeletal maturity?
X-ray of wrist and hand
What is the difference between boys and girls in terms of growth rate during puberty?
- Boys grow slowly first, then accelerate mid puberty
- Girls grow fast at the start, and slow down later on
What is short stature defined as?
Height below the 2nd centile
If a child was dropping off height centiles, what would you want to look at first?
- Weight centile
- Estimated height -MPH