Diagnosis of Osteoporosis

It is important to get a diagnosis for osteoporosis as soon as you experience any of the symptoms associated with the condition. One should not prolong a visit with a doctor because the sooner the diagnosis, the sooner the individual will receive treatment.

About 80% of your bone density is determined by heredity, which is out of your control. However, the other 20% can be controlled by you.

The most common and reliable diagnosis of osteoporosis is done through a check of your bone density, which is done through a BMD test.

BMD test

BMD stands for bone mineral density, which is a measure of the health of your bones. The regular X-ray technology is used to spot bone fractures but they can’t measure bone density. For that, you would need more specialized technology. The most common used technology for this is DXA (dual-energy X-ray absorptiometry), which uses very low radiation levels of X-ray to detect small losses of bone mass. The same technology can be used to measure the bone density of any other bone in your body.

It works by measuring your bone mineral density and comparing it to that of a healthy individual who is the same age and sex as you are. The difference is then measured as a standard deviation (SD) and recorded as your own T-score. Although DXA is mostly used to measure BMD for the spine and hip, the technology can also be altered to perform further specialized tests on other bones:

• DXA (peripheral DXA) measures bone mass at the forearm, finger and heel
• SXA (single-energy X-ray absorptiometry) measures the heel or wrist
• DPA (dual photon absorptiometry) measures the spine, hip or total body
• SPA (single photon absorptiometry) measures the wrist
• QCT (Quantitative Computed Tomography) measures the spine or hip
• PQCT (peripheral QCT) measures the forearm
• QUS (Quantitative Ultrasound) uses sound waves to measure the heel or finger

The amount of SD will then be used to determine whether the level of bone loss in your case can be rated as osteoporosis. The World Health organization has defined the following threshold values for the diagnosis of osteoporosis with the DXA:

Normal	T-score of -1 or above
Osteopenia	T-score lower than -1 and greater than -2.5
Osteoporosis	T-score of -2.5 or lower
Severe Osteoporosis	T-score of -2.5 or lower, and presence of at least one fragility fracture

However, these figures are not the only values considered in your diagnosis; instead, other factors, such as age, sex, and presence of previous bone injuries, have to be taken into account.

The presence of osteoporosis does not mean that you qualify for medication outright either, your doctor may start you off with some therapies available to try and curb the bone breakdown and prevent fracturing.

Other tests for osteoporosis

Although a BMD test has proven to be adequate and effective, sometimes your doctor may recommend a different test. Below is the list of some other tests for BMD:

1. Radiological assessments: ultrasound and quantitative computed tomography (QCT)
2. Fluid tests: blood and urine tests may be used to determine the metabolism of bone
3. Bone densitometry: similar to DXA, this uses X-rays to more accurately measure the density of bone

Most of these alternative tests have only been used in clinical trials and epidemiological studies but aren’t readily available to everyone. For that reason, you can be comfortable with the DXA knowing that it has proven itself time and again.