|
PRACTICAL
SIGNIFICANCE
Stress
fractures
are
markers
of
inheritable
skeletal
problems
that may
place
adolescent
girls at
an
increased
long-term
risk for
osteoporosis.
STUDY
BACKGROUND
Stress
fractures
are
particularly
concerning
in
active
female
adolescents
and
because
they may
signify
insufficiency
of the
bones to
withstand
repetitive
loading.
Although
a
‘fracture
threshold’
is not
yet
defined
for
children
and
adolescents,
approximately
80-90%
of in
vitro
skeletal
strength
in
adults
is
determined
by bone
mineral
density
(BMD). A
woman’s
peak
bone
mass (PBM)
is
achieved
by the
early
20s and
is one
of the
strongest
predictors
of her
long-term
risk of
osteoporosis.
Understanding
the
factors
that
predispose
individuals
to
stress
fractures
in this
population
could
indirectly
elucidate
the risk
factors
associated
with low
BMD.
OBJECTIVE
Increased
physical
activity
and
menstrual
irregularity
(MI)
have
been
associated
with
increased
risk for
stress
fracture
among
adult
women
active
in
athletics.
The
purpose
of this
study
was to
determine
if they
are also
risk
factors
among
adolescents.
DESIGN
AND
SETTING
A
matched
case-control
study
was
conducted
at the
sports
medicine
clinics
of an
urban
tertiary
care
pediatric
medical
center.
SUBJECTS
Patients
who had
participated
in at
least 3
hours
per week
of
physical
activity
were
eligible
for
enrollment.
Patients
with
chronic
illnesses
or use
of
medications
known to
affect
BMD were
excluded.
Each
case
diagnosed
with her
first
stress
fracture
was
matched
prospectively
with 2
controls.
MEASUREMENTS
The
primary
outcome,
stress
fracture
in any
extremity
or the
spine,
was
confirmed
radiographically.
Family
history
and
menstrual
history
were
obtained
by
semi-structured
interview,
with MI
defined
as
primary
or
secondary
amenorrhea
or
oligomenorrhea.
Physical
activity
was
quantified
using a
validated
self administered
questionnaire.
RESULTS
There
was no
significant
difference
in the
mean
hours
per week
of total
physical
activity
between
girls in
this
sample
with
stress
fracture
(8.2
hrs/week)
and
those
without
(7.4
hrs/week,
P=0.51).
The
prevalence
of MI
was
similar
among
cases
and
controls
(21.4%
vs.
14.3%,
P=0.24).
In
multivariate
models,
the only
significant
predictor
of
stress
fracture
was a
positive
family
history
of
osteoporosis
or
osteopenia
(odds
ratio =
2.96,
95%
confidence
interval
[CI]:
1.36,
6.45).
CONCLUSIONS
Among
highly
active
female
adolescents,
only a
family
history
of a low
bone
density
was
independently
associated
with
stress
fracture.
The
magnitude
of this
association
suggests
that
further
investigations
of
inheritable
skeletal
factors
are
warranted
in this
population.
|
Publication
and
Presentation
List:
-
Loud
KJ,
Micheli
LJ,
Bristol
SK,
Austin
SB,
Gordon
CM.
Family
History
Predicts
Stress
Fracture
in
Active
Female
Adolescents.
Pediatrics
2007;
in
press.
-
Loud
KJ,
Gordon
CM,
Bristol
SK,
Austin
SB,
Micheli
LJ.
Predictors
of
Stress
Fracture
in
Active
Female
Adolescents.
Presented
at
National
Athletic
Trainers’
Association
Annual
Meeting,
Atlanta,
Georgia,
15
June
2006.
-
Loud
KJ,
Micheli
LJ,
Bristol
SK,
Austin
SB,
Gordon
CM.
Bone
Mineral
Density
in
Active
Female
Adolescents
with
Stress
Fracture.
Presented
at
American
Society
for
Bone
and
Mineral
Research
Annual
Meeting,
Nashville,
Tennessee,
October
2005.
|
|
Keith J. Loud, M.D
Principal Investigator
|
|
Keith J. Loud received his A.B. degree in Biochemical Sciences from Harvard College, and his M.D. degree from McGill University. Upon completing medical school, Dr. Loud completed his residency at Dartmouth-Hitchcock Medical Center in the Department of Pediatrics, and his fellowship in the Divisions of Adolescent Medicine and Sports Medicine at Children’s Hospital in Boston. Dr. Loud also completed his MS degree in Clinical Sciences from Harvard Medical School during this time. Currently, Dr. Loud serves as the Medical Director of Adolescent Health Services at Children’s Hospital of Akron Ohio. Additionally, Dr. Loud is an Assistant Professor of Pediatrics at Northeast Ohio Universities’ College of Medicine. Dr. Loud is Board Certified by the American Board of Pediatrics in Sports Medicine and Adolescent Health and a member of numerous Pediatric and Sports Medicine societies. |
| |
Keith J. Loud, M.D
Akron Children's Hospital
Center for Orthopedics & Sports Medicine
Considine Professional Building, 7th Floor
215 W. Bowery Street
Akron, OH 44308
(330) 543-3500 or 866-760-1950 |
|
|
This
Grant
Information
Summary
may be
downloaded
in a
2-page
pdf file
from
http://www.natafoundation.org/pdfs/07Loud.pdf. |
Back to
February 27, 2009
eBlast
Newsletter
Send e-mail
to johno@nata.org with questions
or
comments
about this web site. |
