The lower the bone density, the greater the risk of fracture. If you discover that you have osteoporosis, there are several things you can do to reduce the chances that you will break a bone. For instance, you can take osteoporosis medications combined with calcium and vitamin D supplements, and you can do an exercise program.

See "Patient education: Calcium and vitamin D for bone health Beyond the Basics " and "Patient education: Osteoporosis prevention and treatment Beyond the Basics ". Note that if you have previously had a low trauma bone fracture, you are also classified as having osteoporosis and need to take osteoporosis medications, regardless of your bone density T-score.

Fracture prediction tool — Fracture Risk Assessment Tool FRAX is an online tool that was developed to estimate your year likelihood of having a minimal trauma fracture. You can use it to determine your fracture risk even if you have not had a dual-energy x-ray absorptiometry DXA test, but you will get a more accurate prediction if you include DXA results.

If you decide to use the FRAX tool on your own, without a DXA study, and the results indicate a high risk of fracture, then it may be helpful to ask your health care provider whether you can also have a DXA test.

This DXA will serve as a baseline by which your doctor can follow your response to treatment. If the FRAX tool indicates that you have a high risk of fracture, your doctor may also recommend that you start on antifracture medications, regardless of your bone density results.

FRAX should not be used if you have already had a minimal trauma fracture or are already on treatment aimed at preserving your bone health and preventing future fractures.

DO I NEED TO HAVE BONE DENSITY TESTING AGAIN? Even if your bone density test shows that you do not have osteoporosis today, you may need to have the test again. How long to wait between tests depends on your initial bone density results and whether you have risk factors that represent an ongoing threat to your bones.

Repeat bone density measurements may be most valuable for people who are taking a medication to treat osteoporosis to determine the efficacy of treatment and for people who are not being treated but have medical conditions that can cause bone loss to determine if they need treatment.

Bone density tests help health care providers spot bone loss in people who might otherwise have no symptoms. The tests are painless, quick, and safe, and they can alert people to bone loss before they have a fracture.

The tests are also useful in tracking the effects of medications used to manage bone disease. Your health care provider is the best source of information for questions and concerns related to your medical problem. This article will be updated as needed on our website www. Related topics for patients, as well as selected articles written for health care professionals, are also available.

Some of the most relevant are listed below. Patient level information — UpToDate offers two types of patient education materials. The Basics — The Basics patient education pieces answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials.

Patient education: Bone density testing The Basics Patient education: Osteoporosis The Basics Patient education: Calcium and vitamin D for bone health The Basics Patient education: Vitamin D deficiency The Basics Patient education: Primary hyperparathyroidism The Basics Patient education: Hip fracture The Basics Patient education: Vertebral compression fracture The Basics Patient education: Cadmium toxicity The Basics Patient education: Medicines for osteoporosis The Basics.

Beyond the Basics — Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are best for patients who want in-depth information and are comfortable with some medical jargon. Patient education: Osteoporosis prevention and treatment Beyond the Basics Patient education: Calcium and vitamin D for bone health Beyond the Basics.

Professional level information — Professional level articles are designed to keep doctors and other health professionals up-to-date on the latest medical findings.

These articles are thorough, long, and complex, and they contain multiple references to the research on which they are based.

Professional level articles are best for people who are comfortable with a lot of medical terminology and who want to read the same materials their doctors are reading. Clinical manifestations, diagnosis, and evaluation of osteoporosis in postmenopausal women Osteoporotic fracture risk assessment Screening for osteoporosis in postmenopausal women and men.

htm , available in Spanish. org , available in English and Spanish. Why UpToDate? Product Editorial Subscription Options Subscribe Sign in.

Learn how UpToDate can help you. Select the option that best describes you. View Topic. Font Size Small Normal Large. Patient education: Bone density testing Beyond the Basics.

Formulary drug information for this topic. No drug references linked in this topic. Find in topic Formulary Print Share. Outline SUMMARY WHAT DOES BONE DENSITY TESTING DO AND WHY IS IT IMPORTANT? Risk factors for fracture WHICH TEST IS BEST? Dual-energy x-ray absorptiometry Quantitative computerized tomography Ultrasound WHAT TO EXPECT FROM A DXA TEST WHAT DO THE RESULTS MEAN?

Normal bone density Low bone mass osteopenia Osteoporosis Fracture prediction tool DO I NEED TO HAVE BONE DENSITY TESTING AGAIN?

Authors: Joel S Finkelstein, MD Elaine W Yu, MD Section Editor: Clifford J Rosen, MD Deputy Editor: Katya Rubinow, MD Contributor Disclosures. All topics are updated as new evidence becomes available and our peer review process is complete.

Literature review current through: Jan This topic last updated: Sep 29, There are several different types of bone density tests. WHAT TO EXPECT FROM A DXA TEST During dual-energy x-ray absorptiometry DXA , you lie on an examination table.

SUMMARY Bone density tests help health care providers spot bone loss in people who might otherwise have no symptoms. Patient education: Bone density testing The Basics Patient education: Osteoporosis The Basics Patient education: Calcium and vitamin D for bone health The Basics Patient education: Vitamin D deficiency The Basics Patient education: Primary hyperparathyroidism The Basics Patient education: Hip fracture The Basics Patient education: Vertebral compression fracture The Basics Patient education: Cadmium toxicity The Basics Patient education: Medicines for osteoporosis The Basics Beyond the Basics — Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed.

Patient education: Osteoporosis prevention and treatment Beyond the Basics Patient education: Calcium and vitamin D for bone health Beyond the Basics Professional level information — Professional level articles are designed to keep doctors and other health professionals up-to-date on the latest medical findings.

Clinical manifestations, diagnosis, and evaluation of osteoporosis in postmenopausal women Osteoporotic fracture risk assessment Screening for osteoporosis in postmenopausal women and men The following organizations also provide reliable health information.

org , available in English and Spanish [ ]. Incidence and economic burden of osteoporosis-related fractures in the United States, J Bone Miner Res ; Binkley N, Bilezikian JP, Kendler DL, et al.

Summary of the International Society For Clinical Densitometry Position Development Conference. Hodgson SF, Watts NB, Bilezikian JP, et al. American Association of Clinical Endocrinologists medical guidelines for clinical practice for the prevention and treatment of postmenopausal osteoporosis: edition, with selected updates for Endocr Pract ; Raisz LG.

Clinical practice. Screening for osteoporosis. N Engl J Med ; National Osteoporosis Foundation. Clinician's Guide to Prevention and Treatment of Osteoporosis. It does NOT include all information about conditions, treatments, medications, side effects, or risks that may apply to a specific patient.

It is not intended to be medical advice or a substitute for the medical advice, diagnosis, or treatment of a health care provider based on the health care provider's examination and assessment of a patient's specific and unique circumstances.

Osteoporosis is a condition characterized by microarchitectural deterioration of bone tissue leading to decreased bone mass and bone fragility. Both processes are regulated by genetic and environmental factors.

Reduced bone mass is the result of varying combinations of hormone deficiencies, inadequate nutrition, decreased physical activity, comorbidity and the effects of medications used to treat various unrelated medical conditions. Of the approximately 25 million American women who have osteoporosis, 8 million have had a documented fracture.

Osteoporotic fractures are more common in whites and Asians than in blacks and Hispanics, and are more common in women than in men. One possible reason is that blacks and men achieve higher peak bone densities than whites and women.

With respect to women, age-related bone loss accelerates during menopause as estrogen levels decrease. Primary osteoporosis—deterioration of bone mass that is unassociated with other chronic illness—is related to aging and decreased gonadal function. Therefore, early menopause or premenopausal estrogen deficiency states may hasten the development of primary osteoporosis.

Prolonged periods of inadequate calcium intake, sedentary lifestyle and tobacco and alcohol abuse also contribute to this condition. Secondary osteoporosis results from chronic conditions that contribute significantly to accelerated bone loss.

These chronic conditions include endogenous and exogenous thyroxine excess, hyperparathyroidism, malignancies, gastrointestinal diseases, medications, renal failure and connective tissue diseases. Secondary forms of osteoporosis are listed in Table 1. For example, if a pituitary tumor is identified, surgical removal could prevent ongoing accelerated bone loss.

The bone loss already sustained can be treated. The secondary hyperparathyroidism of renal failure can be ameliorated through dietary modification and calcium supplementation.

Because osteoporosis is usually asymptomatic until a fracture occurs, it is crucial to recognize who is at risk and identify the appropriate timing and methods for screening.

Women are more susceptible to osteoporosis than men. However, osteoporosis in men is now recognized as an important health problem, particularly in the aged. Approximately 30 percent of hip fractures in persons older than 65 years occur in men. Osteoporosis-related fracture in older men is associated with lower femoral neck bone mineral density, quadriceps weakness, higher body sway, lower body weight and decreased stature.

Osteoporosis is much more common in older persons and in the ethnic groups previously mentioned. Furthermore, family history of osteoporosis increases the risk. One example of genetically determined osteoporosis is seen in patients with Turner's syndrome 45XO gonadal dysgenesis.

Osteoporosis commonly complicates this syndrome and its genetic variants. Women with this syndrome have low plasma estradiol levels and elevated gonadotropin concentration. Increasing the milk intake of adolescents has been shown to improve bone mineralization. Unquestionably, adolescents must maintain a dietary balance among calcium, protein, other calorie sources and phosphorus.

For example, phosphorus is a substantial component of carbonated drinks, and high phosphorus intake compromises calcium uptake by bone, thereby promoting decreased bone mass. Eating disorders also affect bone mineral density.

Inability to maintain normal body mass promotes bone loss. The body weight history of women with anorexia nervosa is the most important predictor of the presence of osteoporosis. Major demands are placed on the mother by the fetus for calcium during pregnancy and by the infant during lactation.

The axial spine and hip show losses of bone mineral density during the first six months of lactation, but these losses appear to be completely restored six to 12 months after weaning. Sedentary lifestyle and immobility confinement to bed or wheelchair increase the incidence of osteoporosis.

Low body weight and cigarette smoking negatively influence bone mass. Excessive alcohol consumption has been shown to depress osteoblast function and, thus, to decrease bone formation.

Because certain medications negatively affect bone mineral density, these drugs should be avoided, if possible, in those at risk Table 1. The history and physical examination are neither sensitive enough nor sufficient for diagnosing primary osteoporosis.

However, they are important in screening for secondary forms of osteoporosis and directing the evaluation. A medical history provides valuable clues to the presence of chronic conditions, behaviors, physical fitness and the long-term use of medications that could influence bone density.

Those already affected by complications of osteoporosis may complain of upper- or midthoracic back pain associated with activity, aggravated by long periods of sitting or standing, and easily relieved by rest in the recumbent position.

The history should also assess the likelihood of fracture. Low bone density, a propensity to fall, greater height and prior fractures are indications of increased fracture risk.

The physical examination should be thorough for the same reasons. For example, lid lag, and enlargement or nodularity of the thyroid suggest hyperthyroidism. Moon facies, thin skin and a buffalo hump suggest Cushing's syndrome.

Cachexia mandates screening for an eating disorder or malignancy. A pelvic examination is necessary for the complete evaluation of women. Osteoporotic fractures are a late physical manifestation. Common fracture sites are the vertebrae, forearm, femoral neck and proximal humerus. The presence of a dowager's hump spinal curvature in elderly patients indicates multiple vertebral fractures and decreased bone volume.

Basic chemical analysis of serum is indicated when the history suggests other clinical conditions influencing the bone density. The tests presented in Tables 3 7 and 4 5 are appropriate for excluding secondary causes of osteoporosis.

Specific biochemical markers human osteocalcin, bone alkaline phosphatase, immunoassays for pyrinoline cross-links and type 1 collagen-related peptides in urine that reflect the overall rate of bone formation and bone resorption are now available.

These markers are primarily of research interest and are not recommended as part of the basic work-up for osteoporosis.

Controlled trials have yet to prove that women who receive bone density screening have better outcomes i. The U. Preventive Services Task Force suggests that the primary argument for screening is that postmenopausal women with low bone density are at increased risk for subsequent fractures of the hip, vertebrae and wrist, and that intervention can slow the decline in bone density after menopause.

Plain radiographs are not sensitive enough to diagnose osteoporosis until total bone density has decreased by 50 percent, but bone densitometry is useful for measuring bone density and monitoring the course of therapy 19 Table 5.

The most widely used techniques of assessing bone mineral density are dual-energy x-ray absorptiometry DXA and quantitative computerized tomography CT. Of these methods, DXA is the most precise and the diagnostic measure of choice.

Smaller, less expensive systems for assessing the peripheral skeleton are now available. These include DXA scans of the distal forearm and the middle phalanx of the nondominant hand, and a variety of devices for obtaining quantitative ultrasound measurements on bone. The predictive value of these peripheral measures in assessing fracture risk at the hip or vertebrae is not clear.

Ideally, baseline measurements should be taken at a central and a peripheral site. If follow-up measurements are needed to monitor therapy, the peripheral scans can be compared with the original measurements.

Follow-up measures must be obtained using the same instruments to ensure reliability of data. Bone densitometry reports provide a T score the number of standard deviations above or below the mean bone mineral density for sex and race matched to young controls or a Z score comparing the patient with a population adjusted for age, sex and race.

The bone mineral density result enables the classification of patients into three categories: normal, osteopenic and osteoporotic. Normal patients need no further therapy; osteopenic patients should be counseled, treated and followed so that no further bone loss develops; osteoporotic patients should receive active therapy aimed at increasing bone density and decreasing fracture risk.

Osteoporosis is the classification for a T score of more than 2. Decisions to intervene in patients with osteoporosis reflect a desire to prevent early or continuing bone loss, a belief that there can be an immediate impact on the patient's well-being and a willingness to comply with the patient's desires.

Bone densitometry can assist in the decision-making process if the patient's age confers risk, there are no manifestations of disease and the decision point is prevention versus treatment. Medicare currently reimburses costs of bone densitometry when the conditions outlined in Table 6 21 are met. Recognizing the variety of conditions conferring risk of osteoporosis, the National Osteoporosis Foundation makes the following recommendations to physicians:.

Counsel all women on the risk factors for osteoporosis. Perform an evaluation for osteoporosis on all postmenopausal women who present with fractures, using bone mineral density testing to confirm the diagnosis and determine the disease severity.

Recommend bone mineral density testing to postmenopausal women younger than 65 years who have one or more risk factors for osteoporosis in addition to menopause.

Recommend bone mineral density testing to all women 65 years and older regardless of additional risk factors. Advise all patients to obtain an adequate dietary intake of calcium at least 1, mg per day , including supplements if necessary.

Recommend regular weight-bearing and muscle-strengthening exercise to reduce the risk of falls and fractures. Advise patients to avoid smoking and to keep alcohol intake at a moderate level i.

Consider all postmenopausal women who present with vertebral or hip fractures to be candidates for osteoporosis treatment.