Group Fitness Classes Fitness Class Descriptions Personal Training/Private Instruction Health, Wellness & Nutrition Articles

Forearm Bone Scans Predict Overall Skeletal Health

Dr. Ralph Ofcarcik, Ph.D.
Director of Nutrition Services

     According to NIH, one out of every 2 women and 1 out of every 4 men over the age of 50 will have an osteoporosis-related fracture in their lifetimes. The odds look even bleaker if you are thin and have a small frame, are of Caucasian or Asian descent, are a smoker, have used anticoagulants or glucocorticoids for several years, or have had any of a number of bone-depleting diseases (notably Cushing's syndrome, hyperparathyroidism, Graves' disease, leukemia, rheumatoid arthritis, ankylosing spondylitis, malabsorption, or Crohn's disease).

     And although we sometimes think of osteoporosis (literally meaning porous bones) as a tragic affliction of our seniors, the process of depleting our skeleton of calcium and other minerals may have started half a century before the visual manifestations (spinal curvature, hump, decrease in height) became apparent. In other words, osteoporosis is an ongoing, insidious disease that for many begins in our late 20's.

     It seems, once again, Mr. Franklin's advice (i.e. "An ounce of prevention is worth a pound of cure.") is fitting. In my opinion, a reasonable suggestion would be for anyone over the age of 30 to schedule a bone scan, especially if there is a family history of osteoporosis or if any of the aforementioned risk factors are applicable. If your scan results are favorable - congratulations! Simply make an entry on your computer calendar to schedule another test in approximately 5 years. If there is a reason to be concerned, consider lifestyle intervention (weight-bearing exercise, a calcium/key nutrient supplement, 10 minutes of daily sunshine or UV light, avoidance of high-protein diets, etc.) and plan on having a yearly scan coinciding with your annual physical.

     If you have never had your bone mineral density measured, deciding on a methodology can be challenging. Literally, dozens of technologies are commercially available - from portable and relatively inexpensive sonar units (sometimes featured in promos at the local health food store) to gargantuan multi-million dollar computed tomography units, usually housed in hospitals and larger clinics. However, the three major imaging modalities commonly used in a clinical setting include dual energy x-ray absorptiometry (DXA), quantitative computed tomography (QCT), and calcaneal (heel bone) ultrasonography. Overall, DXA is the preferred technology for two reasons: 1. it is the most precise technology for assessing bone fracture risk, and 2. it has the highest reliability for assessing change resulting from lifestyle or medical intervention. It was also the method utilized by WHO (World Health Organization) in the development of their now widely accepted standards for osteopenia and osteoporosis. Although the pricey QCT units offer unique diagnostic capabilities, their higher radiation emissions and somewhat lesser ability to measure fracture risk potential usurp their popularity as a workhorse osteoporosis screening tool. Ultrasound units, although portable and radiation-free, are generally avoided in most clinics because of their low precision.

     For several years, Red Mountain Spa has been offering forearm bone scans on a DXA unit nestled in the Lab Services Room of our Health Services Department. The test, which normally takes about 10 minutes, is conducted on the non-dominant arm and measures the weight of minerals (grams) over a pre-defined area (cm²) where the forearm bones (ulna and radius) meet at the wrist. Bone mineral density (g/cm²) is then plotted on a chart which compares the bone health to people of all ages of the same gender. Interpretation of the data is based upon WHO recommendations and a statistical t-test using standard deviations as markers:

     How accurate is wrist bone mineral density in predicting bone health in other parts of the skeleton? According to recent studies the combined bone mineral densities of the ulna and radius on the non-dominant arm are very reliable measurements for predicting osteoporosis on potential key fracture sites (especially the spine and thighbone, i.e. femur). For anyone who has ever had a bone fracture, however, measurement at the injury site is always advised.

You can make an appointment to have this valuable testing done during your next Red Mountain Spa visit by calling the spa at 1-800-690-9215.