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ABOUT
BONE DENSITOMETRY
Introduction
Different Techniques
Dexa or Ultrasound?
BONE
DENSITOMETRY EQUIPMENT
Types of Equipment
New or Preowned?
Operator Requirements
BONE
DENSITOMETRY PRACTICE
Why offer Bone Densitometry?
Indications for Bone Densitometry
Patient Reimbursements
Favorable Legislation
ABOUT
OSTEOPOROSIS
Basic Facts
Not Just a Woman's Disease
Prevention & Treatment
Links
INTEGRITY'S
B D EQUIPMENT PROGRAM
Why Bone Densitometry is Important
Now
How IMS Can Help
TERMS OF USE
© 2004, Integrity Medical Systems, Inc. |
ABOUT OSTEOPOROSIS
Basic Facts
206 bones consisting of hard,
rigid tissue make up the skeletal framework of our bodies,
to which muscles are attached and within which organs are
housed. Bones are made up of proteins, sugars, minerals and
other materials. They are living, changing tissues that produce
blood cells and act as a storehouse for calcium and phospate.
The human skeleton is a remarkable structural system in which
a range of bodily activities take place.
During youth, bones grow in length and density.
During the teen years, maximum height is reached, but bones continue
to grown more dense until about age 30 when peak bone density is attained.
After that point, bones slowly start to lose density or strength. Thorughout
life, bone density is affected by heredity, diet, sex hormones, physical
activity, lifestyle choices, and the use of certain medications. When
a person's bone structure is undermined, the failure of function that
can be experienced can be devastating. We've seen the extent of this
physical devastation in the most common bone disease - osteoporosis.
The word osteoporosis is from the Greek osteon
for "bone" and porus for "pore" or "passage." Indeed, osteoporosis
literally makes your bones more porous. The percentage of calcium stored
in your bones decreases over time . The structural integrity of trabecular
bone (in the middle of the bone e.g., vertebrae and at the end
of the long bones) is impaired. Cortical bone (the dense outer layer
of bone) becomes more porous and thinner. When the skeleton is in this
weakened condition, fractures occur.
Until recently, before enhanced prevention, diagnosis (using DEXA bone densitometry
equipment ) and treatment made it possible to fight the disease, osteoporosis
was considered an unavoidable part of the aging process. Indeed, most cases
of osteoporosis are the result of an acceleration of the normal changes our
bodies undergo as we age. Unfortunately, 1 of every 4 women older than 45 years
and 9 of 10 women older than 75 years have varying degrees of osteoporosis.
[UPDATE: recent studies indicate that the numbers of women with osteoporosis
may actually be higher. A December 2001 study by the Columbia University College
of Physicians and Surgeons found that nearly one out of every two women in
a test of 200,000 healthy women aged 50 and older had undetected low bone-mineral
density.]
These women have primary osteoporosis, which
gradually depletes the store of calcium in the bones; this form usually
becomes more evident after the onset of menopause. Only 84% of young
women have normal bone density. By the age of 50, that percentage falls
to 60%. Men start with a larger reserve of bone materials, and so their
loss of bone density due to ostepororis becomes evident later in life.
See below for more on Men and Osteoporosis.
Secondary osteoporosis occurs when the disease accompanies endocrine disorders
such as acromegaly and Cushing's syndrom, or when it results from excessive
use of drugs like corticosteroids.
Above: In a 61 year old female, AP spine
T-Score indicates osteopenia{-1.2} while her lateral spine t-score
shows ecidence of osteoporosis {-3.0}. The AP measurement may be artificially
elevated due to arthritic or other degenerative changes.
A committee of the World Health Organization
has defined osteoporosis based on the bone density. Using standard
bone density measurements of the total hip, "normal" bone is greater
than 833 mg/cm 2. Low bone mass, called "osteopenia," is between 833
and 648 mg/cm 2. Osteopenia is the designation for bone density between
1.0 and 2.5 standard deviations below the mean for young normal adults
(T-score between -1 and -2.5). Osteoporosis is lower than 648 mg/cm
2, or a bone density 2.5 or more standard deviations below the young
normal mean (T-score at or below -2.5). "Severe (established) osteoporosis" is
when at least one fragility- related fracture has occurred.
Osteoporosis poses a dire threat for millions
of Americans. According the National Institutes of Health, 10 million
Americans have been diagnosed with osteoporosis, and 18 million more
have have low bone mass levels indicative of developing osteoporosis
in the future. It is the most prevalent of the bone diseases that affect
Americans, and leads to over 1.5 million fractures each year. 300,000
of those are hip fractures. Approximately 700,000 are vertebral fractures;
250,000 are wrist fractures; and 300,000 fractures occur at other sites.
Above: Smart medicine today makes sense
for the future.
Osteoporosis is now considered the second
largest public health problem for women. In 1995, hospital and nursing
home costs alone tallied for osteoporotic and associated fractures
was $13.8 billion per year. Without increased access to screening and
treatment, the disease could drive up costs to an estimated $30 billion
per year by 2020.
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Men and Osteoporosis: Not Just a Woman's
Disease
Osteoporosis is not just a woman's disease,
and there are compelling reasons for men to join the fight for better
access to screening and more equitable reimbursements for screening.
Two million of the total 10 million individuals diagnosed with osteoporosis
in 1995 were male. Another 3 million men are at risk. Studies completed
in 1994 showed that a 50-year old man has a remaining lifetime risk
of osteoporotic fracture of 13%. And experiencing such a fracture has
more dire implications for men than for women: While the rate of hip
fractures is two to three times higher in women than men, the one year
mortality following a hip fracture is nearly twice as high for men
as for women.
The statistics paint a chilling portrait of the future for men suffering from
osteopororis. Each year, men suffer 1/3 of all the hip fractures that occur,
and 1/3 of these men will not survive more than a year. Over 100,000 men have
a hip fracture every year; one third of these men will die of complications
from their hip fracture within a year. Of the survivors, more than a quarter
will not walk again without assistance. In addition to hip fracture, men also
experience painful and debilitating fractures of the spine, wrist, and other
bones due to osteoporosis. Yet, despite the large number of men affected, and
men's greater likelihood of death or crippling disability after a hip fracture,
osteoporosis in men remains underdiagnosed, underreported, and inadequately
researched. As preventive screeing for osteoporosis in postmenopausal women
garners the medical attention it so desperately needs, male osteoporosis is
allowed to progress silently for decades -- unitl a dangerous fracture occurs.
Men's risk factors for osteoporosis:
_ Prolonged exposure to medications such
as sterioids used treat asthma or arthritis, anticonvulsants, certain
cancer treatments and aluminum-containing antacids
_ Chronic disease that affects the kidneys, lungs, stomach, and intestines
and alters hormone levels
_ Undiagnosed low levels of the sex hormone testosterone
_ Lifesyle habits such as smoking; excessive alcohol use; low calcium intake;
inadequate physical exercise; age
_ Heredity
_ Race: While white men appear to be at greatest risk for osteoporois, men
from all ethnic groups develop the disease.
Diagnosing Osteoporosis in Men
A man's physician should take a medical history
to identify risk factors and and conduct a complete physical exam,
including height, weight, x-rays, and urine and blood tests. The diagnosis
of osteoporosis is done by a Bone Mineral Density Test, or bone mass
measurement, a special type of x-ray that can diagnose osteoporosis.
A man should report to his physician any loss of height, change in
posture, or sudden back pain.
The Male Osteoporosis Challenge
Men at risk for osteoporosis face a crucial
stage in their ability to detect the disease. While the evaluation
of osteoporosis in men is similar to that of women, the crucial Bone
density measurement tests are not reimbursed as readily for men as
for women. Under the current Medicare law, it is very difficult for
a man to be reimbursed for a bone mass measurement test. In February
of 2001, the Honorable Constance A. Morella of Maryland introduced
to the House of Representatives the Medicare Osteoporosis Measurement
Act of 2001. The Act was proposed to extend bone density screening
to men being treated for prostrate cancer, since the testosterone suppression
therapies used to control advanced prostate cancer also predisposes
these men to osteoporosis.
Detection
Specialized tests called bone
density tests can measure bone density in various sites
of the body, i.e., hip, spine, and peripheral sites such
as the heel or finger. A bone density test is currently
the only effective way to:
*Detect osteoporosis before a fracture occurs
*Predict your chances of fracturing in the future
*Determine your rate of bone loss
*Monitor the effects of treatment if the test is conducted annually
Unfortunately, for most people suffering from osteoporosis, their first symptom
is a fracture. A hip or wrist may break with a minor fall or accident, although
in some cases spontaneous hip fractures precipitate the fall. Vertebral fractures
rarely require surgical treatment, but if they become extensive they can cause
painful backaches. When bones are weakened severely, osteoporosis can be crippling.
The disorder is also associated with an estimated 40,000 deaths annually, largely
from complications of surgery or immobilization after hip fractures.
Prevention & Treatment
By about age 20, the average
female has acquired 98% of her skeletal mass. Building
strong bones during childhood and adolescence can be the
best defense against developing osteoporosis later. According
to the National Osteoporosis Foundation, there are four
steps to prevent osteoporosis. No step alone is enough
to prevent osteoporosis, but all four may. They are:
*A balanced diet rich in calcium and vitamin D
*Weight-bearing exercise
*A healthy lifestyle with no smoking or excessive alcohol intake,
and
*Bone density testing and medication
According to a report in the October 22nd issue of the Archives of Internal
Medicine, fluoride, in combination with calcium and vitamin D, increases bone
mass and lowers the risk of backbone fractures associated with osteoporosis.
The study, conducted by Dr. Craig D. Rubin from the University of Texas Southwestern
Medical Center at Dallas, compared fluoride, calcium, and vitamin D with calcium
and vitamin D alone in the treatment of 85 women aged 65 years or older who
had already experienced one or more backbone fractures from osteoporosis. The
fluoride used was a long-acting form. Women treated with fluoride saw a 68%
reduction of new or repeat fractures compared with women who did not receive
fluoride. Women treated with fluoride showed significant improvements in various
measures bone formation compared with women not treated with fluoride, suggesting
that fractures were prevented by bone remodeling and bone formation. None of
the ill effects previously associated with the use of higher doses of fluoride
were seen in these patients. "Our findings support the use of (long-acting)
sodium fluoride with calcium and (vitamin D) in treating older ambulatory women
with established osteoporosis," Rubin and colleagues conclude.
Rubin's findings could revolutionize treatment of osteoporosis, however, it
is important to note that there is currently no FDA-approved drug for osteoporosis
that increases bone formation. Although there is no cure for osteoporosis at
this time, the following medications are approved by the FDA for postmenopausal
women to either prevent and/or treat osteoporosis:
*Estrogens (registered brand names such as Premarin, Ogen, Estrace,
Estraderm, and Estratab, etc.)
*Alendronate (registered brand name Fosamax) is also approved as
a treatment for men
*Calcitonin (registered brand name Miacalcin)
*Raloxifene (registered brand name Evista)
*Risedronate (registered brand name Actonel)
*Alendronte is approved for prevention and treatment of glucocorticoid-induced
osteoporosis in men and women.
*Treatments under investigation include sodium fluoride (see above);
vitain D metabollites; parathyroid hormone; and other bisphosphonates and SERMs.
Links
National Osteoporosis Foundation
National institutes of Health Osteoporosis and Related Bone Diseases National
Resource Center
Bone Measurement Institute (**note sponsored by Merck)
Lunar Corporation
Integrity Medical Systems,
Inc.
State
of Florida Bureau of Radiation Control
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