A DEXA scan or Dual Energy X-ray Absortiometry scan is a diagnostic tool that measures bone mineral density. This type of scan is usually prescribed for those at increased risk of osteoporosis. p DEXA or peripheral DEXA is used to measure bones on the periphery of a person such as wrist, fingers and heels. Central DEXA is used to measure bones in the spine and hip. This type of DEXA scan can accurately measure low bone density and is the preferred test for diagnosing osteoporosis. An imager passes over your body, emits radiation from two different sources in alternation. The DEXA scan differs from the regular bone scan in that the use of 2 different x-ray energy sources provides precision and accuracy. Besides it is able to detect loss of bone density much earlier than when it can surface on a regular x-ray. A detector measures the amount of radiation that comes through the bone being examined. This throws light on its density. A Dexa scan usually takes about 20 minutes and involves small amount of radiation.
Literally meaning 'porous bones', osteoporosis is a medical condition that is characterized by fragile skeletal structure. Osteoporosis threatens nearly 34 million women in the US alone and many more worldwide. Osteoporosis is commonly noticed in post-menopausal women. But actual loss of bone mass happens in the 30s. This occurs due to loss of lose an excessive amount of their protein and mineral content, particularly calcium from the bones. Over time it leads to reduced bone mass and decreased bone strength. Normal bone marrow has small holes within it, but a bone with osteoporosis will have much larger holes. Osteoporosis can be classified into two categories - primary and secondary. Primary osteoporosis is associated with bone loss, which is prevalent in older persons and post menopause women. Secondary osteoporosis results from chronic conditions that contribute significantly to accelerated bone loss.
Most often osteoporosis is caused by a combination of lifestyle, genetic and hormonal factors. Slender, small-framed women are particularly at risk. Typical symptoms of osteoporosis are severe back pain, curvature of the spine and loss of height. A woman suffering from osteoporosis suffers from joint aches and muscle aches. There is an increased tendency to fractures on account of brittle and thin bones. Osteoporosis can be hereditary. Women with very thin body frames can be at increased risk of osteoporosis on account of lesser bone mass. Prolonged use of corticosteroids can put a woman at increased risk of osteoporosis since drugs such as prednisone, cortisone, prednisolone and dexamethasone damage bone mass. Other medications that can lead to bone loss are diuretics, anti-seizure drugs and anticoagulants. Hyperthyroidism is another contributory factor to developing osteoporosis. Chronic conditions such as renal failure, malnutrition and connective tissue diseases contribute towards development of osteoporosis.
Diagnosis of osteoporosis may include a series of tests such as bone densitometry (a bone density scan) performed by your physician. There are three types of bone density scans: dual-energy x-ray absorptiometry (DEXA), single photon absorptiometry (SPA), and quantitative computed tomography (QCT). The most common bone density scan is the DEXA - a test that measures bone density based on how bone absorbs two sets of photons (atomic particles with no electrical charge) generated by an x-ray tube. A bone density test is recommended by physicians to post menopausal women, especially those with a higher risk factor.
It is essential to build on your bone mass during the ages of 25 - 35 so as to keep osteoporosis at bay. This can be done by maintaining a balanced diet, with plenty of calcium and following a regular exercise regimen. Weight-bearing exercises are of special importance in strengthening the bones. Running, skipping, aerobics, tennis and weight training are ideal osteoporosis exercises that can be undertaken thrice a week for at least 30 minutes. Apart from bone density, these exercises also increase the strength, co-ordination and balance, thereby reducing the risk of falls. A sedentary lifestyle can put you at increased risk of developing osteoporosis in latter years.
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Collection of Pages - Last revised Date: March 21, 2019