Adolescence comprises a period in the life cycle between childhood
and adulthood. Biological, psychological, social, environmental, and
legal changes influence the definitive onset and termination of
adolescence. Pubescence is often described as the onset of adolescence;
however, the mean age of onset of puberty in girls in the United States
varies by race and is earlier than in previous generations. The
mean age of onset for white girls is 9.7 years with a range of onset
from 7.8 to 11.6 years; and for black girls, 8.1 years with a range
of onset from 6.1 to 10.1 years. In boys, the onset of puberty has remained
stable at 11.4 years of age with a range of 9.5 to 13.51-6 (see Chapter 540). For purposes of discussion in
this section, adolescence in chronologic years is defined as the period
from 10 to 21 years.
All bodily tissues are affected by the biological changes of
puberty. Growth of the reproductive, cardiovascular, and musculoskeletal
systems is closely correlated during this period. The major biological changes
occurring during puberty can be classified into 6 groups: skeletal
growth, alterations in body composition, cardiorespiratory changes,
hematologic development, neuroendocrine development, and reproductive
maturation. Chronologic age does not always correlate with biological
maturity. Sexual maturation rating (SMR) stages, as originally described
by Tanner and Marshall, provide a more accurate assessment of the
biological developmental stage of the adolescent (see Chapter 540).7,8
The secondary growth spurt at pubescence accounts for approximately
25% of final adult height.9 As outlined
in Table 63-1,10 the growth spurt
for girls occurs at an earlier sexual maturity rating (SMR 2–3)
than for boys (SMR 4). Girls reach a final mean adult height of
163.8 cm at a mean age of 16 years compared with 176.8 cm for boys
at a mean age of 18 years. Assessment of skeletal growth during
adolescence is done through the use of a height-velocity curve with
consideration of the gender-specific sexual maturity rating. Bone
age can be determined through the use of a hand roentgenogram.11
Table 63-1. Clinical
Correlates of Pubertal Maturation |Favorite Table|Download (.pdf)
Table 63-1. Clinical
Correlates of Pubertal Maturation
|SMR 1||SMR 2||SMR 3||SMR 4||SMR 5|
|Alkaline phosphatase (IU/L) (serum)|
|Black (mean) ||84||95||86||44||31|
|Slipped capital femoral epiphysis||+||++|
|Acute worsening of scoliosis||+||++||+|
|Peak height velocity||+||++||+|
Log In to View More
If you don't have a subscription, please view our individual subscription options below to find out how you can gain access to this content.
Want remote access to your institution's subscription?
Sign in to your MyAccess profile while you are actively authenticated on this site via your institution (you will be able to verify this by looking at the top right corner of the screen - if you see your institution's name, you are authenticated). Once logged in to your MyAccess profile, you will be able to access your institution's subscription for 90 days from any location. You must be logged in while authenticated at least once every 90 days to maintain this remote access.
If your institution subscribes to this resource, and you don't have a MyAccess profile, please contact your library's reference desk for information on how to gain access to this resource from off-campus.
AccessPediatrics Full Site: One-Year Subscription
Connect to the full suite of AccessPediatrics content and resources including 20+ textbooks such as Rudolph’s Pediatrics and The Pediatric Practice series, high-quality procedural videos, images, and animations, interactive board review, an integrated pediatric drug database, and more.
Pay Per View: Timed Access to all of AccessPediatrics
24 Hour Subscription $34.95
48 Hour Subscription $54.95
Pop-up div Successfully Displayed
This div only appears when the trigger link is hovered over.
Otherwise it is hidden from view.