3
The Diagnosis
Learning Objectives
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One morning, Mrs. Donofrio, 68 years old, felt a sharp pain in her back when she
bent over and picked up her 4-year-old granddaughter. The pain remained acute
even after several doses of over-the-counter pain medications and hours of bed
rest. Mrs. Donofrio consulted her doctor who suggested that she come in the next
day for testing. Because Mrs. Donofrio had several risk factors for
osteoporosis, her doctor suspected that she may have fractured a vertebra.
Osteoporosis is a disease that progresses silently over a long period of time.
If it is diagnosed early enough, the fractures associated with the disease can
be prevented. Unfortunately, osteoporosis often remains undiagnosed until a
fracture occurs.
An examination to diagnose osteoporosis involves several steps. An initial
physical examination will be performed, followed by various radiological and
laboratory tests. Radiological tests can detect bone density, skeletal
abnormalities, and fractures. Laboratory tests reveal important information
about the metabolic process of bone breakdown and formation. The physician may
need to perform a variety of diagnostic tests before choosing an optimal
treatment strategy.
Before any tests are performed, your physician will record your lifestyle and
medical history, paying special attention to osteoporosis risk factors. Your
doctor will ask you questions related to your family history of disease,
including osteoporosis, your history of taking medications, your general intake
of calcium and vitamin D, your exercise patterns, and for women, your menstrual
history. The doctor will note medical problems and medications that you may have
been taking which can contribute to bone loss.
The general physical examination will include evaluation of your height and posture. In particular, the physician will look for changes in height and curvature of the spine (known as kyphosis).
The following are some of the procedures and tests your physician may order.
Radiology
If you have back pain and the doctor suspects a fracture, she or he will order an x-ray of the spine. The doctor may also order an x-ray if a loss of height or change in posture has been detected.
A bone mass measurement will be ordered by the doctor to confirm the diagnosis of osteoporosis when a vertebral fracture has been detected by x-ray, when risk factors are present, or when other signs point to osteoporosis. The bone mass measurement, also known as a bone density test, differs from an x-ray. Like an x-ray, a bone mass measurement is a non-invasive and painless procedure in which an energy source is passed over part or all of the body. An ordinary x-ray cannot, however, detect bone loss until 25-40% of the skeleton has been depleted. A bone mass measurement allows a physician to see how much bone mass you have and, since bone mass serves as an approximate measure of bone strength, helps the physician establish your risk of future fractures. Bone mass measurement is the only way to detect low bone mass and make a definitive diagnosis of osteoporosis.
In addition to diagnosing osteoporosis, a bone mass measurement can often be helpful when deciding whether to begin a prevention or treatment program. Physicians also use bone mass measurements to monitor the effects of treatment. If you are on a treatment to prevent bone loss, a bone mass measurement conducted at yearly intervals or so can help determine whether the treatment is effective.
These types of equipment may be used:
![]() | Radiographic Absorptiometry (RA) |
![]() | Single-Photon Absorptiometry (SPA) |
![]() | Dual-Photon Absorptiometry (DPA) |
![]() | Single Energy X-Ray Absorptiometry (SXA) |
![]() | Dual Energy X-ray Absorptiometry (DXA), and |
![]() | Quantitative Computed Tomography (QCT). |
The radiation exposure of these devices is extremely low, although QCT has a
somewhat higher level of exposure. The effectiveness of these devices for
detecting low bone mass is comparable.
In selected patients, a bone scan may be ordered. A bone scan is different from
the bone mass measurement tests described above, although the term "bone
scan" is often used (mistakenly) for bone mass measurements or bone density
tests. A bone scan can tell the physician whether there are changes, which may
indicate cancer, bone lesions, inflammation, or new fractures. To perform a bone
scan, the patient is injected with a dye, which allows the scanner to reflect
differences in the condition of tissues.
Laboratory Tests
In addition to radiological tests, a number of laboratory tests may be performed on blood and urine samples. The results of blood and urine tests can give your doctor an idea of your bone turnover, that is, how rapidly your bones are breaking down (resorption) and building up (formation). Your doctor will know the normal ranges for these tests.
Blood Tests
![]() | Chemistry profile: Measures overall health status, including calcium levels. |
![]() | Thyroid function: Evaluates overall metabolic rate. |
![]() | Parathyroid function: Measures stability of normal calcium levels. |
![]() | Vitamin D metabolites: Measures stability of normal calcium levels. |
Hormone levels
![]() | Estradiol (estrogen) |
![]() | Follicle Stimulating Hormone (FSH): To establish menopausal status and provide baseline measurement of bone- protective hormones. |
Testosterone
![]() | Osteocalcin: Marker of bone formation. |
![]() | Serum electrophoresis: Evaluates immune cell function. |
Urine Tests
![]() | 24-hour calcium and creatinine or spot calcium level: Evaluates calcium metabolism. |
![]() | Hydroxyproline: Marker of bone resumption. |
![]() | Pyridinolines: Marker of bone resumption. |
Other Procedures
Malabsorption studies are blood tests which are performed on selected patients to evaluate the absorption of nutrients.
Infrequently, when the diagnosis of osteoporosis is unclear, the physician must perform a bone biopsy in order to rule out osteomalacia (a vitamin D-deficiency disease), or other unusual disorders. A small piece of bone from the top of the hip is removed. A bone biopsy is usually performed in an outpatient surgical setting with sedation.
Once you and your physician have definitive information based on your history, physical examination, and diagnostic findings, a specific treatment program will be developed for you. Recommendations for optimizing bone health include adequate calcium and vitamin D intake and appropriate exercise. In addition, specific medical treatment may be prescribed which will help you preserve bone mass and prevent fractures. If you have already fractured, your doctor may refer you to a specialist in physical therapy and rehabilitation. Also, information on how to fall-proof your environment may be offered, as well as information on the availability of an osteoporosis support group in your area.
Source: National Osteoporosis Foundation