Osteoporosis is a condition which thins and weakens your bones, making you more likely to break (fracture) bones, even from minor knocks, bangs, or falls. People with osteoporosis most commonly experience fractures of the spine, hip, or wrist.
There
are approximately 28 million Americans affected by this "silent" disease,
and most of them are not even aware of the condition until a fracture occurs.
Although osteoporosis is a significant health problem for many Americans, it
is most common in middle-aged women. As many as one in two women and one in
five men, over age 50, will suffer a fracture related to osteoporosis during
their lifetime.
What
causes osteoporosis?
Your
bones are made of living tissue. Although you are not aware of this, your bones
are always changing. They are being both eroded and rebuilt in two, on-going
activities which together are called "remodeling".
In
your teens and twenties, the "rebuilding" dominates, and your bones
get stronger and stronger. In your thirties and forties, the two activities
more or less balance each other out, and your bones reach their peak strength.
Peak bone strength depends on many factors, including genetics, lifestyle (diet
and exercise), medication and chronic illness. After the age of forty, the "eroding"
becomes dominant, and over time your bones gradually weaken.
Normally,
there is no cause for concern - remodeling is part of the natural life cycle
for us all. However, if you develop osteoporosis, "rebuilding" slows
down earlier, or "eroding" speeds up, or both. With osteoporosis,
the net result is that your bones become weaker than those of other people your
own age, and you have a greater tendency to fracture.
Who
is prone to osteoporosis?
If
you are a postmenopausal woman, you are in the group who will most likely be
affected by osteoporosis. With the onset of menopause, your body slows its production
of the important hormone, estrogen. This hormone was important during your reproductive
years, and also helped to keep your bones strong.
There
are other risk factors which may lead to osteoporosis. These include a family
history of osteoporosis, a small, light body frame, smoking and alcohol consumption,
a lack of exercise, and long-term use of certain drugs such as corticosteroids,
and early menopause.
How
do you check if you are at risk for osteoporosis?
The
best place to start is with your doctor. He or she will review your entire medical
history, and if there is concern for osteoporosis, he/she may advise you to
have a bone check-up. The results of this test, combined with your medical history,
will help your doctor decide if you have, or might develop, osteoporosis.
What
kind of bone check-ups are there?
Until
the 1970's and 1980's, the best way to check your bones was to x-ray your hip
or spine. An experienced radiologist could see from the x-ray if your bones
were in trouble. But weak bones are only visible once they are significantly
damaged and have already partially collapsed. So this test was ineffective as
an "early warning system", and it was unwise to expose people to unnecessary
radiation. Therefore, clinicians and engineers worked together to develop better,
safer methods for earlier bone testing.
In
the 1970's and 1980's, special radiological tests were developed to help detect
osteoporosis earlier. These tests are called Bone Mineral Density (BMD) tests.
BMD has been the most popular method for checking bone. Its measurements tell
the doctor how much bone there is at a particular site on your body, referred
to as your bone density. The lower the density, the weaker your bone, and the
more prone you are to fracture. The measurement can be performed at various
sites such as the spine, hip, arms and legs. BMD measurements also involve radiation,
although at a much lower level than traditional x-rays.
In
1998, a new technology was approved by the U.S. Food and Drug Administration
for testing your bones. This new method, called "Bone Sonometry",
is based on ultrasound, similar to the ultrasound that doctors use to check
pregnant women and their unborn babies. If you are reading this pamphlet, it
is likely that your doctor has chosen to test your bones with this new generation
of equipment, called "Bone Sonometers".
BMD
and Bone Sonometry are not always used on the same sites of the body, and results
of the tests are not always the same. Each technology measures somewhat different
things, at different places. Nevertheless, since osteoporosis is a generalized
disease, affecting your entire skeleton, it can be detected at various body
sites. Your doctor understands this, and knows how to interpret the results
so that the two of you can make more informed decisions about your health.
Why
use ultrasound to check bones? Ultrasound has a long and successful history,
dating back to the early 1900's. It has been widely used in industry to detect
defects or flaws in materials - for example, cracks in airplane wings and pipelines.
Bone sonometry uses similar principles to provide information about your bones.
The ultrasound waves pick up important information about your bones' density,
elasticity, and thickness. Today's ultrasound bone sonometers measure at the
arm or leg. It's fast, comfortable, dependable, and most importantly, radiation
free.
How
is an ultrasound bone check-up done?
You
will either sit in a chair or lie on your back on an examination table, with
one leg outstretched. The length of your tibia (shin bone) will be measured,
and a line will be marked on the skin at the middle, using a skin marker. Standard
ultrasonic gel will be applied to the skin, and the operator will move the scanner
back and forth along the midline. This may be repeated on your other leg, too.
What
should you wear?
You
only need to expose your leg, from the knee down. It is best that you wear loose
fitting pants or a skirt. If you wear pantyhose, you'll need to remove them.
How
long! does this check-up take?
The
whole test only takes about 10-15 minutes.
Are
there any risks involved in ultrasound bone testing?
No,
ultrasonic waves used in medical applications do not present any known risk
or side effects.
Test
results and their meaning!
Your
ultrasound bone check-up provides three important pieces of information:
1.
The first is the actual score of your test (it's actually a measurement of how
fast ultrasound waves travel through your bone, called "Speed Of Sound",
or "SOS" for example,
3850 meters per second).
2.
Next, your results are compared with those of typical young, healthy people
of your sex, and summarized in a number called a "T-score".
3.
Finally, your results are compared with those of people your own age and sex,
and summarized in the third and final number, the "Z-score".
All
this information is then printed out, along with the results of previous check-ups
you've had at the same centre. By the way, the meaning and significance of the
"T" and "Z" scores for both ultrasound and BMD are very
similar. Because of this, most doctors will understand both types of results.
Having
a low result does not mean that you will definitely fracture your bones in the
future. Your doctor knows how to interpret the numbers, and can discuss with
you what these results mean.
What
should you do with the results?
Your
doctor will advise you as to what is best to do. If your test results indicate
that your bones may be weak, he/she will probably suggest preventative measures
and/or prescribe medications. How your doctor helps you care for yourself depends
upon many factors. In any event, you can help your bones by:
·
1998
Myriad Ultrasound Systems Inc.
Extracted
from Myriad Ultrasound “Soundscan Compact” User’s Guide – Patient Information.
Myriad
Ultrasound Systems Ltd.