Low bone density is most commonly associated with osteoporosis, an age-related disorder that consists of decreased bone mass and increased susceptibility to fractures. Osteoporosis is most commonly seen in postmenopausal women, with about 1.2 million fractures per year attributed to the condition, and of these fractures, about one-third are compressed fractures of the spine. Lately, doctors are finding that the trend of those diagnosed with low bone density is changing: an increasingly large amount of men, younger women and even children are being diagnosed with decreased bone mass. Many of those diagnosed with the condition were not fully aware of their susceptibility.

After the first bone fracture, patients have a 20% chance of another occurring within 1 year, leading to a cascade of fractures.

Of patients undergoing a hip replacement surgery due to low bone density, 20% will die within 1 year of the surgery. Medical professionals are unanimous in their claims that bone densitometry exams need to gain more exposure to men, women and children. New technology allows for patients to be diagnosed and treated in a more efficient manner, thus offsetting the morbidity that results in osteoporosis-related fractures.

To detect osteoporosis accurately, Main Street Radiology uses an enhanced form of x-ray technology called dual-energy x-ray absorptiometry (DEXA). DEXA bone densitometry is today's established standard for measuring bone mineral density (BMD). DEXA is a quick, painless procedure for measuring bone loss. Measurement of the lower spine and hips are most often done.

The DEXA test can also assess your risk for developing fractures. If the bone density is found to be low, the patient and referring physician can work together on a treatment plan to help prevent fractures before they occur. DEXA is also effective in tracking the effects of treatment from osteoporosis or for other conditions that can cause bone loss.

Indications for bone mineral density (BMD) testing: 

• Women age 65 and older 
• Postmenopausal women under age 65 with risk factors.
• Men aged 70 and older
• Adults with fragility fracture
• Adults with a disease or condition associated with low bone mass or bone loss. 
• Adults taking medications associated with low bone mass or bone loss. 
• Anyone being considered for pharmacologic therapy for bone loss. 
• Anyone being treated for bone loss, to monitor treatment effect.
• Anyone not receiving therapy in whom evidence of bone loss would lead to treatment

Women discontinuing estrogen should be considered for bone density testing according to the indications listed above.

The result of the DEXA bone density are interpreted by a board-certified radiologist. The radiologist will send an interpretation of the results and a signed report to the referring physician, who will work with the patient to develop a treatment plan. Test results will be in the form of two scores:

T-score: This number shows the amount of bone the patient has compared to a young adult of the same gender with peak bone mass.

Z-score: This number reflects the amount of bone the patient has compared to other people in their age group and of the same size and gender. If it is unusual high or low, it may indicate a need for further medical tests.

Diagnosis in postmenopausal women is made via the World Health Organization (WHO) criteria.

Normal : T-score -1.0 or above 
Osteopenia: T-score between -1.0 and -2.5 
Osteoporosis: T-score -2.5 and below

Serial BMD testing can be used to determine whether treatment should be started on untreated patients, because significant loss may be an indication for treatment. Serial BMD testing can monitor response to therapy. Intervals between BMD testing should be determined according to each patient's clinical status. Typically one year after initiation or change of therapy is appropriate, with longer intervals once therapeutic effect is established. In conditions associated with rapid bone loss, such as glucocorticoid therapy, testing more frequently is appropriate.