What is Osteoporosis? | What causes Osteoporosis? | How is Osteoporosis diagnosed? | How can Osteoporosis be treated?


How is Osteoporosis diagnosed?


Osteoporosis is diagnosed most easily and accurately by bone density measurements, even though its presence can be inferred from the physical examination and plain X-rays. X-rays cannot detect osteoporosis early in the course of the disease when it is most treatable. X-rays of many parts of the body (the wrist, hand, shoulder, spine, pelvis, ankle and foot) can often suggest the presence of advanced osteoporosis, but not until late in the disease, when treatment is difficult. There are currently several methods to determine bone density. These include:

  • DEXA Duel energy scans, which are performed with very low dose radiation measurements of bone density in the spine, pelvis, hip, forearm, wrist or the heel.
  • ultrasound measurements of the heel
  • special X-rays of the hand and wrist which compare the hand bone density with aluminum phantoms placed next to the bones at the time of the X-ray
  • CT (Computed Tomograph) scans of the spine and hand and hip, using special programs and algorithms.

Ultrasound scans, plain x-rays, and CT scans require special programs and equipment to measure bone density, and are more costly or less accurate than DEXA scans. DEXA scans have become the most commonly used and cost effective method of osteoporosis detection in the past several years. DEXA scans of all parts of the body yield results which are proportional and comparable to each other and therefore a scan of one part of the body gives results which are applicable to the entire body, and comparable to each other. There is some evidence that scans of specific parts of the body have an increased ability to predict fractures at that particular site. At the present state of the art, it is best to make sure the same machine and the same body location be used when performing follow up scans to determine the progression or regression of bone density. Medicare now will pay for scans of different parts of the body for more accurate follow up.

How is Osteoporosis is determined from DEXA scans?
Your scan determined bone density is compared via a computer program with results of bone densities averaged from large groups of young (20 to 30 year old) females or males of the same ethnic group. The values obtained from you are compared with the mean of the young person group and are reported by the computer as a number + or - the standard deviation of the group. These calculations are done automatically by the software that is attached to the scanner. Values between -1 and -2.4 are considered Osteopenia, thin bones not yet osteoporotic. Bone density values that are 2.5 standard deviations or more below the healthy young females (or males) means are considered to be osteoporosis. All dexa scans also report the scan results in grams/cm2. At the Osteoporosis Center I have seen bone densities as low as -8.2. Values this low are usually associated with severe bone pain. Values above -3.5 are usually painless. Mild to moderate osteoporosis is truly a silent disease. >>